Oh man. Read your blog. When i switched off my amps, i always switched first the standby and then the power off. So i did it wrong the last 40 years... Thanks!
Thanks Dr Z!!! I was watching a few other videos on how the Standby switch is not needed, but NONE of them mentioned the need of the Standby switch with amps that have a Solid State Rectifier!! My amp has one! So I'm glad I found your video on the use case FOR the standby switch! I may have screwed up my (very expensive) tube amp had I followed those other videos... yikes!! Thank you Dr. !!
Thanks for clearing up this bullshit. I just read an article on Pro Audio Land that "explained" how it's "critical for your tone" to leave your amp on stand-by for at least half an hour before you play a note or your tone will suck for the next two sets. Then Carvin's website says that you will not only ruin your whole gig and hurt your tubes, but you will even "damage your amp" if you dare play through it without going through the elaborate and "essential" stand-by ritual first. Did I just fry my capacitors and create bad tone karma for my next seven lifetimes? I don't know one way or the other, but I believe you do. Thank you Dr. Z for being a beacon of truth and reason in a sea of senseless lies & stupidity.
I do have a solid state rectified amp and use the standby switch when turning it ON. When turning the amplifier OFF I was told to NOT use the standby switch to "let the capacitors drain gracefully " I hope this is correct because I've been doing it this way for 35 years! Lol Keep up the good work Dr. Z.
I never use the standby switch for breaks between sets. I was always afraid of “plate stripping”. And old guy I knew that was an excellent amp tech told me “the standby switch isn’t a mute switch. Then he told me about plate stripping of your power tubes. It sounded sensible to me. He told me the biggest reason for standby switches originally was to protect the caps. Because the caps that were available back then were actually more fragile than today’s caps. You hear so many opinions and stories it’s hard to know what to think if you’re not an electrical engineer. To be honest, my standby switch on my amp broke on my amp in the operate position years ago and I’ve been to lazy to have it replaced. I just turn my amp on and off. That’s it. Never a problem with tubes or anything else doing it that way. For breaks between sets I just turn the volume down. I like my tubes to stay hot and ready between sets.
@@DrZAmplification Ah! Yep. That’s what it was. Cathode stripping. I didn’t remember correctly. Definitely not an electrical or amp expert. It’s been at least 30 years since he told me that. Thanks for replying and for your videos!
You could just pull the lead out of you amp a bit like the Doc said, I do when I use a little fender amp and it is silent when pulled out a notch but ready to cook as soon as you plug back in.
Thank you for this video and for your blog. Also, for taking the time to answer so many questions. I did find the “Dos and don’ts” of the blog confusing as you switched from saying “engage the standby switch” (which I took to mean put it in the on position) to saying put it in the on or off position. In the blog it sounds like you are saying to leave the amp in playing mode during breaks and mute it by pulling out the cable or with a tuner. I apologize if this is obvious to everyone but me. Ha!
I guess I've always used the stand by switch like a mute button. I put the amp in standby before I switch guitars because I don't like the loud pop when you plug in to a hot amp. I've seen guys use their pedal tuners as a mute too. Just kick on your tuner and switch guitars. I've never seen anyone have electrical problems with either method. I'll also put the amp in standby if I'm taking a short break. I'm also in the habit of engaging the standby for a few minutes while my amp warms up and for a few minutes before I turn it off... judging by the video and the comments, I'm probably wasting my time but I've never had a problem with my method. Also I'm so OCD I'm not sure I could change now lol. Rock on amigos and thanks Dr. Z. 🎸 🎶 🎵
i just wish amps w/standby came with explicit instruction not to leave the amp in standby for extended periods! most musicians i know (myself included) are operating under the assumption that this is included in the intended functions of such a part. this is a fantastic overview! i thought it was brilliant to point out the standby's usefulness to the technician first and foremost, i agree completely but hadn't really considered that! also worth noting that there are some standbys that are literal mute switches only, such as the one on the Silvertone 1484/Twin Twelve, which simply mixes the two halves of the output signal together to cancel each other out. i think these would be relatively ok to leave in standby for long periods? besides the normal wear of having the tubes on and idling, of course. but i have heard that it is primarily 1) extended periods in cutoff, and 2) drastic and swift temperature changes (such as when turning the amp on/off) which wears the cathode out the most. this leads me to believe that using the Silvertone's mute-standby switch for long periods would be advantageous for certain situations, like a by-the-hour recording session or a gig with multiple sets, because it would be less wear than switching it on and off a buncha times... i'm probably overthinking it! the only advantage to a true high-voltage killing standby that i'm aware of that you didn't mention, is it can protect your filter caps from over-voltage spikes upon startup, which is especially important if your amp is vintage (esp. 40's & 50's), because the increase in wall voltage over the years could push them above their voltage tolerances!
Can't remember what the model name is but there is a "Brown box" power regulator that goes between thecwall and the amp plug. You can set it to the exact V you amp needs like 117 V on those old amps from 50s. Brown box?
There's many on youtube saying standby switch is not needed but then why does it make a loud pop sound in the speakers if i turn off standby and imediately turn off the amp without waiting a few seconds?
I actually was under the impression that stand by was to help protect the tubes from on and off again power to them. Ei, warming and cooling of the element's within the tube itself. Live and learn. Tnx!
I've left my Vox ac15 with power on and in standby mode for 2 or 3 days a couple of times, and it ended up in the repair shop to replace tubes and a tube seat once. The Vox is designed with the controls on top, so it isn't obvious at a glance what switches are on or off. I am now very conscious of making sure both switches are in the off position before I leave the room.
I assumed standby just controlled power to the speaker. Recently, I blew an EL84 tube when I switched from standby to play. I was surprised this could happen given my assumption as to how it worked. Now I know better and understand how my issue occurred. Thank you!
Dr Z, im an amp newbie.i recently got a Monoprice Stage Right 15W. Q: would it be a good idea to use the 1W feature as a sort of standby? (it has no real standby switch)
Switching to stand by is fine. Even better, disconnecting the guitar from the amp, that way no signal is present. No signal, no potential for output, no harm to the output transformer.
I just like the convenience of leaving the amp on stand-by after a soundcheck or in the break of a show.Plus , it's ONE more switch !! And Marshalls look good with it.
I have an EMS. My dealer suggested I engage the standby switch when shifting between SS and Tube rectification. But on the Dr. Z forum the consensus is that it is not necessary. Your comments in this vid make me think the dealer was right. albeit...the amp is already on and the tubes heated when I do that...so I guess they aren't getting slammed as you discuss when initially powering...the tubes are already warm so they aren't "shocked"? Btw, love the EMS! My other amps are all Mesa's and the EMS is just amazingly more articulate and just plain "musical" by comparison....oh...and I can actually find the tones I am looking for....that's a big plus too.
Under normal operating circumstances, it shouldn't be a problem, but your are switching high voltage when using the SS/tube switch. It would not hurt disconnecting the high voltage (B+) by using the standby switch before you change the rectification method. It's the safer method, but it unlikely to harm anything if you don't, as long as both the switch and tube rectifier are in good condition.
Thanks for taking the time to do weekly AMA. My question is, do I need to replace my preamp tubes regularly? Some people say every year or two? Should I expect to replace my v1 and v2 more often than my reverb send and return tubes? What about the phase tube or the rectifier? I saw your great AMA in the power tubes of the max 18 so I know I won’t change those. Thanks...Sam
Nope, if the preamp tubes are not making any noises, and the amp sounds good to you, don't change them. Preamp tubes last many many years longer than power tubes, as they are under much less voltage than a power tube is. The same goes with a rectifier. A rectifier will either do it's job, or it won't, and you will know. No need to replace it if the amp is working correctly. Simply put, "new" tubes don't mean "good" tubes, the only "good" tubes are ones that are currently working properly, regardless of age. Remember the cardinal rules: "if it ain't broke..."
Is it necessary to pop the amp into standby after playing it for a few hours? I always heard that was the main purpose, to let it cool down before turning it completely off.
Check the blog post that Doc refers to. It's better Not to use the standby when you are powering down the amp. It drains the electricity from the components if you don't use the standby when you power down.
I have a friend that recently purchased a fender hot rod deluxe Limited edition from GC it had a quite noticeable rattle in one of the output tubes we found which tube was the culprit by holding a pencil eraser on the two different tubes while he played his guitar through it until we found the bad one it was under warranty he took it back got a second hot rod deluxe same problem we have heard about tube baffles and dampers maybe that amp should come with them installed if they’re going to rattle when the amp is brand new what do you think a solution is or should he try a different brand of amplifier
How about a standby that mutes the signal rather than cutting the HT, shorting the PI grid to ground, or like the Silvertone 1484 which cleverly shorts the out of phase grids of the power tubes together? Probably makes a loud pop and running sensitive grid wires from the board to the faceplate could be problematic.
Can you build a dolby atoms amp/mixer? minimum 5.1.2 setup? Would that require a parametric eq for the Sub or a 60k-100k low pass filter? Just asking for everybody here in 2042...
The way I do it with my Mesa is - Standby then power on - Power off then standby off. And I use standby when switching equipment or taking small breaks, but never leave it in standby for long periods.
Hey DR. Z, I have a VOX AC30 CC2 I recently blew my rectifier when turning the standby switch off before the master. I just want to be clear on this. you said with a tube rectifier it's basically not needed to turn on with stand by. With a solid state rectifier, it won't hurt using the standby to allow for the heaters to warm up. So my amp has a 5AR4 rectifier tube, so your saying that it would not matter if i permanently left the standby switch in the on position, and only used the master on/off to turn the amp on and off? Thanks!
Yes. In fact there is a design flaw in this model of the AC30 which causes this that is well documented online. Just never use that standby, and you will be fine.
@@DrZAmplification Thank you for the verification! I have one more question, once I turn the power switch on do I need to take a minute before I play so the tubes to warm? or can it take playing right when I flip the power switch on?
@@robertwilson7813 by virtue of the rectifier tube needing to warm to conduct the hi voltage to the power tubes, there will be a natural 15-30 second warm up. Once you hear sound, you can start playing.
I read in either Guitar Player or Vintage Guitar magazins - BEFORE the internet and all the crap on it - if you warm the amp up on standby, and turn it off, NOT on standby your power tubes will last longer. It is a useful circuit.
I use it to mute the amp when I'm changing pedals out or changing guitars or anything like that- or kicking on a pedal that has that horrible pop when the foot switch is engaged. What causes that? I have a couple EHX pedals like that- sounds like a shotgun blast when I engage the footswitch. Anyway- I thought that was the intended use because yes, you can turn the volume down or turn it off but- anyone who has sat in front of their amp bumping parameters this way and that for an hour tweaking everything perfectly to get that perfect tone- you don't want to have to turn it down or anything just to go take a piss. And I don't like turning it off and on repeatedly, I do think that stresses the tubes unnecessarily. Every time they heat up and cool down, they expand and contract- that can't be good for them. But i find it very useful as a mute while being able to leave all parameters (vol. included) in place. Volume on a tube amp is more than just volume- it changes the characteristics of tone the amp is producing- sometimes slightly, sometimes drastically. I guess that's old news to anyone used to using tube amps- I just got one- I've always played solid state- over 20 years I played nothing but solid state. Not really by choice- couldn't afford a tube amp and tbh- I always assumed that like most other things ppl were exaggerating, it couldn't sound that much better. Plus, I grew up in the late 70s- 80s- solid state became the "in" thing there for a minute- and that happened to be when I started playing, so at first, I wanted solid state. We all did- we wanted solid state, high gain amps- to play Metallica, Van Halen, etc. -- Peavey was the hot thing. But see that's the curse- you buy a Peavey- they never tear up- and you play that damn thing forever. Hard to justify buying an amp when yours is still rocking away- and is even a desirable model- I had the Studio Pro 112 Transtube. And I still have it- and yep, still works- I finally just gave up and bought something new anyway. And I'm glad I did- Blackstar club 40 MKII- and it sounds amazing. I was a little concerned about it being a 40w amp, a "gigging" amp they kept stressing- but it's not too loud for the bedroom- not for my bedroom anyway.
How is the standby switch circuit designed? Leo Fender's design was okay for techs but it's kind of sketchy for players. Valco often shorted the push & pull circuits together effectively making it into a mute switch. As for "cathode poisoning" that can happen without even running the tubes. GE only warrantied spare tubes for 1 year whether they were ever used or not. They were also prorated at 1 year so after 6 months you only got a $1 credit on a $2 tube. RCA also had some wonderful insights on vacuum tube aging in some of their "internal use only" technical documents.
I have burned 3 GZ34's cuz I forgot my amp in stanby over a 10yr period with my Z-28. Pilotlight was out so thats why i forgot so easily. I have learned my lesson now and never leave it in standby mode, and yes i also changed my bulb
Why don't we see more amps with stereo xlr (combojack) di outputs built in with isolated paths to and from clean and OD1/OD2? It would be nice to have a ground lift... imagine if that same di had a 5g wireless output ;). I guess my question is why dont we see more innovative amp concepts? (it cant be because cost) Thanks and love your work.
No. With a tube rectifier it's basically not needed. With a solid state rectifier, it won't hurt using the standby to allow for the heaters to warm up.
I accidentally left my tube amp on standby overnight and everything seems fine. What would have happened if I didn't have the standby and had it fully running?
@@jralanmorgan yes, heating the cathodes up for very long increments of time without high voltage being conducted to the plates isn't the healthiest thing for them. better to have them conducting
I've adopted the same approach recently with an orange AD30. It's also GZ recitifed. I used to keep the amp on standby while it warmed up, you could hear an instant blooming hum when you flicked the standby off which I assume had to do with the voltage spike. When you flick both switches on at once, there's no such noise. The amp comes to life slowly but smoothly.
@@ummagumma7826 That's weird. In a fender the standby switch is after the rectifier and shouldn't effect it in any way. I use it during warm up to reduce plate oxidation on the power tubes. warming it up without it causes the plates to try pulling in electrons that aren't there yet, causing oxidation.
@@deanallen927 I blew the fuse in an old AC30, you know amps better than me, I'm not sure about anything you mentioned. The AC30 I have, and still play with no problems since never using the standby, is an older model from before the China made ones
@@ummagumma7826 That could be it. Maybe those older ones had the switch before the rectifier which could be a problem if the transformer is providing a bit of a slowdown, protecting the tube, then engaging the switch sends the full jolt. Fender and Marshall have the switch the standard way, further down, after the first filter stage or similar. while we're at it, I'd recommend not trying the Groove Tubes diode module rectifier replacement; unless you want to have your power caps beefed up. Tube rectified amps typically have/need less filtering because the diode rectifiers send in a quicker more powerful jolt that needs a heavier Twin style cap array.
I always warm up my amps on standby to reduce plate oxidation on the power tubes. warming it up without it causes the plates to try pulling in electrons that aren't there yet, causing oxidation. With the rectifier being way before the standby switch, I don't under stand how you could hurt it.
Thanks for this Dr Z. Basically there is no solid reason for a standby switch. All the reasons for maybe needing one are easily dealt with by another method. I read that the reason Leo Fender used them was because of the limited values of filter caps at that time. The current at startup easily charged the caps and thus full B+ was applied to the tubes before they had heated up. So the standby switch allowed the tubes to heat up before B+ was supplied to the tube. With larger caps, the inrush is soaked up so the rise in B+ is slower, giving time for the tubes to heat up. Therefore no standby needed. With solid state rectifiers and large caps there is no need for a standby switch. So if you are building an exact copy of an early Fender tube amp a standby could be added. Maybe. Many early amps did not. The RCA manual does not even mention standby for receiving amplifiers…it states they are only for high power transmission amplifiers.
Dear doctor... will you ever make a version of the Antidote with two foot switchable channels? And is it possible to order an Antidote with an FX loop added? Love your videos. You seem like a great human being. I wish Z amps all of the success in the world. Your work ethic and knowledge is truly admirable.
Is it just me or does 30 Dr Z watts of EL84 power sound and feel much louder than 30 watts of 6L6 power from competing amp companies? Is it just Z magic or is it the tubes? #ama
I have my amp unplugged. It is a Fender Reverb Deluxe. When I want to play, I plug it then turn the Power Switch on then I wait like 5 minutes and turn the Standby on making the amp to start working and I can play. When I turn it off I go first to standby, switch it off then I turn the power off. Is that procedure correct? Don I need to use the standby to play at all? Thanks.
A cathode follower is a part of the preamp section and there is no high voltage on a cathode follower. High voltage in the preamp is typically found on the plate. The stand by switch turns off high voltage from the power supply to the positive rail, which is useful during maintenance, though not always necessary. The cathode of most tube circuits is comparatively negative, or close to zero voltage. It's strange to find a video with thousands of views from tube amp aficionados across the world, and it's only you who seems to know the correct answer.
So basically it kills the power so the repairman doesn’t get electrocuted. I guess just shutting the amp off with the power switch is too complicated 🙄
The standby switch is completely unnecessary. Don't use it - just turn off the amp or turn down the volume. It does nothing to protect the tubes and it is not a "mute switch" - that is completely different electronically.
@@DrZAmplification That was more true in the old tweed amps that Fender first put them in. Not really true any longer as the capacitor components that Leo was trying to protect are not that expensive today. The standby was primarily to protect the cheaper capacitors he put in the amps as it was cheaper than putting in larger capacitors at that time. The reality is that amp manufacturers aren't concern about amp techs and they could save their customers money by eliminating the switch.
@@DrZAmplification But you would save end users of the amp much more than that from repairs on an unnecessary component that can break. The only reason is there on most modern amps is because amp buyers expect it to be there and don't realize it is not needed.
Oh man. Read your blog. When i switched off my amps, i always switched first the standby and then the power off. So i did it wrong the last 40 years... Thanks!
Thanks Dr Z!!! I was watching a few other videos on how the Standby switch is not needed, but NONE of them mentioned the need of the Standby switch with amps that have a Solid State Rectifier!! My amp has one! So I'm glad I found your video on the use case FOR the standby switch! I may have screwed up my (very expensive) tube amp had I followed those other videos... yikes!! Thank you Dr. !!
Amps probably the single most important part of any guitar/bass setup and often the most misunderstood…Thanks Dr. Z!
🎸🔊🎶🤘
Thanks for taking the time to answer that question. Up until now I've been operation under some false pretenses..
Thanks for clearing up this bullshit. I just read an article on Pro Audio Land that "explained" how it's "critical for your tone" to leave your amp on stand-by for at least half an hour before you play a note or your tone will suck for the next two sets. Then Carvin's website says that you will not only ruin your whole gig and hurt your tubes, but you will even "damage your amp" if you dare play through it without going through the elaborate and "essential" stand-by ritual first. Did I just fry my capacitors and create bad tone karma for my next seven lifetimes? I don't know one way or the other, but I believe you do. Thank you Dr. Z for being a beacon of truth and reason in a sea of senseless lies & stupidity.
Put a lot into perspective as far as building guidelines and rule of thumb goes, thanks Dr. Z!
I do have a solid state rectified amp and use the standby switch when turning it ON. When turning the amplifier OFF I was told to NOT use the standby switch to "let the capacitors drain gracefully " I hope this is correct because I've been doing it this way for 35 years! Lol Keep up the good work Dr. Z.
that's correct. probably wise to use a stand by on a SS rectifier amp
Hey, it's done you okay 4 35 years!! The proof of the pudding is in the eating.
I never use the standby switch for breaks between sets. I was always afraid of “plate stripping”. And old guy I knew that was an excellent amp tech told me “the standby switch isn’t a mute switch. Then he told me about plate stripping of your power tubes. It sounded sensible to me. He told me the biggest reason for standby switches originally was to protect the caps. Because the caps that were available back then were actually more fragile than today’s caps. You hear so many opinions and stories it’s hard to know what to think if you’re not an electrical engineer. To be honest, my standby switch on my amp broke on my amp in the operate position years ago and I’ve been to lazy to have it replaced. I just turn my amp on and off. That’s it. Never a problem with tubes or anything else doing it that way. For breaks between sets I just turn the volume down. I like my tubes to stay hot and ready between sets.
You are referring to cathode stripping and it doesn’t happen in amps with this amount of voltage. He is correct though. It’s not a mute switch.
@@DrZAmplification Ah! Yep. That’s what it was. Cathode stripping. I didn’t remember correctly. Definitely not an electrical or amp expert. It’s been at least 30 years since he told me that. Thanks for replying and for your videos!
@@sgholt no, the filament is there to heat the cathode.
You could just pull the lead out of you amp a bit like the Doc said, I do when I use a little fender amp and it is silent when pulled out a notch but ready to cook as soon as you plug back in.
Thank you for this video and for your blog. Also, for taking the time to answer so many questions. I did find the “Dos and don’ts” of the blog confusing as you switched from saying “engage the standby switch” (which I took to mean put it in the on position) to saying put it in the on or off position. In the blog it sounds like you are saying to leave the amp in playing mode during breaks and mute it by pulling out the cable or with a tuner. I apologize if this is obvious to everyone but me. Ha!
I know it's confusing, so maybe that needs an update. We now refer to it in the "run" or "stop" positions.
I guess I've always used the stand by switch like a mute button. I put the amp in standby before I switch guitars because I don't like the loud pop when you plug in to a hot amp. I've seen guys use their pedal tuners as a mute too. Just kick on your tuner and switch guitars. I've never seen anyone have electrical problems with either method. I'll also put the amp in standby if I'm taking a short break. I'm also in the habit of engaging the standby for a few minutes while my amp warms up and for a few minutes before I turn it off... judging by the video and the comments, I'm probably wasting my time but I've never had a problem with my method. Also I'm so OCD I'm not sure I could change now lol. Rock on amigos and thanks Dr. Z. 🎸 🎶 🎵
i just wish amps w/standby came with explicit instruction not to leave the amp in standby for extended periods! most musicians i know (myself included) are operating under the assumption that this is included in the intended functions of such a part.
this is a fantastic overview! i thought it was brilliant to point out the standby's usefulness to the technician first and foremost, i agree completely but hadn't really considered that!
also worth noting that there are some standbys that are literal mute switches only, such as the one on the Silvertone 1484/Twin Twelve, which simply mixes the two halves of the output signal together to cancel each other out. i think these would be relatively ok to leave in standby for long periods? besides the normal wear of having the tubes on and idling, of course. but i have heard that it is primarily 1) extended periods in cutoff, and 2) drastic and swift temperature changes (such as when turning the amp on/off) which wears the cathode out the most. this leads me to believe that using the Silvertone's mute-standby switch for long periods would be advantageous for certain situations, like a by-the-hour recording session or a gig with multiple sets, because it would be less wear than switching it on and off a buncha times... i'm probably overthinking it!
the only advantage to a true high-voltage killing standby that i'm aware of that you didn't mention, is it can protect your filter caps from over-voltage spikes upon startup, which is especially important if your amp is vintage (esp. 40's & 50's), because the increase in wall voltage over the years could push them above their voltage tolerances!
Can't remember what the model name is but there is a "Brown box" power regulator that goes between thecwall and the amp plug. You can set it to the exact V you amp needs like 117 V on those old amps from 50s. Brown box?
There's many on youtube saying standby switch is not needed but then why does it make a loud pop sound in the speakers if i turn off standby and imediately turn off the amp without waiting a few seconds?
I actually was under the impression that stand by was to help protect the tubes from on and off again power to them. Ei, warming and cooling of the element's within the tube itself. Live and learn. Tnx!
I've left my Vox ac15 with power on and in standby mode for 2 or 3 days a couple of times, and it ended up in the repair shop to replace tubes and a tube seat once. The Vox is designed with the controls on top, so it isn't obvious at a glance what switches are on or off. I am now very conscious of making sure both switches are in the off position before I leave the room.
Pull the plug out of the wall. Lightning etc.
I assumed standby just controlled power to the speaker. Recently, I blew an EL84 tube when I switched from standby to play. I was surprised this could happen given my assumption as to how it worked. Now I know better and understand how my issue occurred. Thank you!
Does it also help with the high voltage from the output transformer when the speaker needs to be quickly disconnected? Thanks!
Best to just turn the amp off before disconnecting the speaker.
Dr Z, im an amp newbie.i recently got a Monoprice Stage Right 15W.
Q: would it be a good idea to use the 1W feature as a sort of standby? (it has no real standby switch)
It doesn't matter, the stand by is not necessary.
Is it safe to change the impedance knob and connected load by switching a running amp to standby first? Or wise to shut off the amp first
Switching to stand by is fine. Even better, disconnecting the guitar from the amp, that way no signal is present. No signal, no potential for output, no harm to the output transformer.
thank you very much for real good pro stuff , Dr Z !!
I just like the convenience of leaving the amp on stand-by after a soundcheck or in the break of a show.Plus , it's ONE more switch !!
And Marshalls look good with it.
Would love to know witch of of your amp's is stronger in midrange? & if it has f86
What are the differences can one expect from a tone tubby hemp vs a celestion vintage 30 speaker?
I have an EMS. My dealer suggested I engage the standby switch when shifting between SS and Tube rectification. But on the Dr. Z forum the consensus is that it is not necessary. Your comments in this vid make me think the dealer was right. albeit...the amp is already on and the tubes heated when I do that...so I guess they aren't getting slammed as you discuss when initially powering...the tubes are already warm so they aren't "shocked"? Btw, love the EMS! My other amps are all Mesa's and the EMS is just amazingly more articulate and just plain "musical" by comparison....oh...and I can actually find the tones I am looking for....that's a big plus too.
Under normal operating circumstances, it shouldn't be a problem, but your are switching high voltage when using the SS/tube switch. It would not hurt disconnecting the high voltage (B+) by using the standby switch before you change the rectification method. It's the safer method, but it unlikely to harm anything if you don't, as long as both the switch and tube rectifier are in good condition.
Thanks! I will continue to do it as a rule, but not especially worry about rigid adherence either.
Thanks for taking the time to do weekly AMA. My question is, do I need to replace my preamp tubes regularly? Some people say every year or two? Should I expect to replace my v1 and v2 more often than my reverb send and return tubes? What about the phase tube or the rectifier? I saw your great AMA in the power tubes of the max 18 so I know I won’t change those. Thanks...Sam
Nope, if the preamp tubes are not making any noises, and the amp sounds good to you, don't change them. Preamp tubes last many many years longer than power tubes, as they are under much less voltage than a power tube is. The same goes with a rectifier. A rectifier will either do it's job, or it won't, and you will know. No need to replace it if the amp is working correctly. Simply put, "new" tubes don't mean "good" tubes, the only "good" tubes are ones that are currently working properly, regardless of age.
Remember the cardinal rules: "if it ain't broke..."
Is it necessary to pop the amp into standby after playing it for a few hours? I always heard that was the main purpose, to let it cool down before turning it completely off.
Check the blog post that Doc refers to. It's better Not to use the standby when you are powering down the amp. It drains the electricity from the components if you don't use the standby when you power down.
I have a friend that recently purchased a fender hot rod deluxe Limited edition from GC it had a quite noticeable rattle in one of the output tubes we found which tube was the culprit by holding a pencil eraser on the two different tubes while he played his guitar through it until we found the bad one it was under warranty he took it back got a second hot rod deluxe same problem we have heard about tube baffles and dampers maybe that amp should come with them installed if they’re going to rattle when the amp is brand new what do you think a solution is or should he try a different brand of amplifier
he should probably get a Z since we put them on our amps and make sure they don't rattle before they leave the shop...
How about a standby that mutes the signal rather than cutting the HT, shorting the PI grid to ground, or like the Silvertone 1484 which cleverly shorts the out of phase grids of the power tubes together? Probably makes a loud pop and running sensitive grid wires from the board to the faceplate could be problematic.
Could thermistors be used on a tube amp that has a solid state rectifier to protect the tubes (and other components) in place of a standby switch?
Sure, but it's not that big of a consideration as to justify the addition parts.
I assume it wasn't for bands that were getting ready to go on stage and they were told "Stand by"
Can you build a dolby atoms amp/mixer? minimum 5.1.2 setup? Would that require a parametric eq for the Sub or a 60k-100k low pass filter? Just asking for everybody here in 2042...
The way I do it with my Mesa is - Standby then power on - Power off then standby off. And I use standby when switching equipment or taking small breaks, but never leave it in standby for long periods.
Good stuff. Maybe a link to the blog in the description?
Done
Hey DR. Z, I have a VOX AC30 CC2 I recently blew my rectifier when turning the standby switch off before the master. I just want to be clear on this. you said with a tube rectifier it's basically not needed to turn on with stand by. With a solid state rectifier, it won't hurt using the standby to allow for the heaters to warm up. So my amp has a 5AR4 rectifier tube, so your saying that it would not matter if i permanently left the standby switch in the on position, and only used the master on/off to turn the amp on and off? Thanks!
Yes. In fact there is a design flaw in this model of the AC30 which causes this that is well documented online. Just never use that standby, and you will be fine.
@@DrZAmplification Thank you for the verification! I have one more question, once I turn the power switch on do I need to take a minute before I play so the tubes to warm? or can it take playing right when I flip the power switch on?
@@robertwilson7813 by virtue of the rectifier tube needing to warm to conduct the hi voltage to the power tubes, there will be a natural 15-30 second warm up. Once you hear sound, you can start playing.
I read in either Guitar Player or Vintage Guitar magazins - BEFORE the internet and all the crap on it - if you warm the amp up on standby, and turn it off, NOT on standby your power tubes will last longer. It is a useful circuit.
I use it to mute the amp when I'm changing pedals out or changing guitars or anything like that- or kicking on a pedal that has that horrible pop when the foot switch is engaged. What causes that? I have a couple EHX pedals like that- sounds like a shotgun blast when I engage the footswitch. Anyway- I thought that was the intended use because yes, you can turn the volume down or turn it off but- anyone who has sat in front of their amp bumping parameters this way and that for an hour tweaking everything perfectly to get that perfect tone- you don't want to have to turn it down or anything just to go take a piss. And I don't like turning it off and on repeatedly, I do think that stresses the tubes unnecessarily. Every time they heat up and cool down, they expand and contract- that can't be good for them. But i find it very useful as a mute while being able to leave all parameters (vol. included) in place. Volume on a tube amp is more than just volume- it changes the characteristics of tone the amp is producing- sometimes slightly, sometimes drastically.
I guess that's old news to anyone used to using tube amps- I just got one- I've always played solid state- over 20 years I played nothing but solid state. Not really by choice- couldn't afford a tube amp and tbh- I always assumed that like most other things ppl were exaggerating, it couldn't sound that much better. Plus, I grew up in the late 70s- 80s- solid state became the "in" thing there for a minute- and that happened to be when I started playing, so at first, I wanted solid state. We all did- we wanted solid state, high gain amps- to play Metallica, Van Halen, etc. -- Peavey was the hot thing. But see that's the curse- you buy a Peavey- they never tear up- and you play that damn thing forever. Hard to justify buying an amp when yours is still rocking away- and is even a desirable model- I had the Studio Pro 112 Transtube. And I still have it- and yep, still works- I finally just gave up and bought something new anyway. And I'm glad I did- Blackstar club 40 MKII- and it sounds amazing. I was a little concerned about it being a 40w amp, a "gigging" amp they kept stressing- but it's not too loud for the bedroom- not for my bedroom anyway.
A GZ34 rectifier tube ( or other indirectly heated cathode rectifier ) will protect your filter caps from spikes on switch on.
How is the standby switch circuit designed? Leo Fender's design was okay for techs but it's kind of sketchy for players. Valco often shorted the push & pull circuits together effectively making it into a mute switch. As for "cathode poisoning" that can happen without even running the tubes. GE only warrantied spare tubes for 1 year whether they were ever used or not. They were also prorated at 1 year so after 6 months you only got a $1 credit on a $2 tube. RCA also had some wonderful insights on vacuum tube aging in some of their "internal use only" technical documents.
I have burned 3 GZ34's cuz I forgot my amp in stanby over a 10yr period with my Z-28. Pilotlight was out so thats why i forgot so easily.
I have learned my lesson now and never leave it in standby mode, and yes i also changed my bulb
Why don't we see more amps with stereo xlr (combojack) di outputs built in with isolated paths to and from clean and OD1/OD2? It would be nice to have a ground lift... imagine if that same di had a 5g wireless output ;). I guess my question is why dont we see more innovative amp concepts? (it cant be because cost) Thanks and love your work.
Is it bad to turn a tube amp on without standby
No. With a tube rectifier it's basically not needed. With a solid state rectifier, it won't hurt using the standby to allow for the heaters to warm up.
So if Elvis was Leo Fender Jim Marshall would be an Elvis tribute artist?
Doc, I love these vids here, you GOTTA keep em coming!!! Cheycaster
I accidentally left my tube amp on standby overnight and everything seems fine. What would have happened if I didn't have the standby and had it fully running?
Likely nothing in both cases however the later would have been the better case.
@@DrZAmplification it would have been preferable for it to be fully on instead of standby? Did I read that right?
@@jralanmorgan yes, heating the cathodes up for very long increments of time without high voltage being conducted to the plates isn't the healthiest thing for them. better to have them conducting
@@DrZAmplification oh wow, thanks for that knowledge!
I never use the standby in my AC30CC. It is known to blow tubes. Instead, I let the GZ34 just warm up normally. No problems.
same, blew fuses and a GZ34 using the standby on my AC30
I've adopted the same approach recently with an orange AD30. It's also GZ recitifed. I used to keep the amp on standby while it warmed up, you could hear an instant blooming hum when you flicked the standby off which I assume had to do with the voltage spike. When you flick both switches on at once, there's no such noise. The amp comes to life slowly but smoothly.
@@ummagumma7826 That's weird. In a fender the standby switch is after the rectifier and shouldn't effect it in any way. I use it during warm up to reduce plate oxidation on the power tubes. warming it up without it causes the plates to try pulling in electrons that aren't there yet, causing oxidation.
@@deanallen927 I blew the fuse in an old AC30, you know amps better than me, I'm not sure about anything you mentioned. The AC30 I have, and still play with no problems since never using the standby, is an older model from before the China made ones
@@ummagumma7826 That could be it. Maybe those older ones had the switch before the rectifier which could be a problem if the transformer is providing a bit of a slowdown, protecting the tube, then engaging the switch sends the full jolt. Fender and Marshall have the switch the standard way, further down, after the first filter stage or similar. while we're at it, I'd recommend not trying the Groove Tubes diode module rectifier replacement; unless you want to have your power caps beefed up. Tube rectified amps typically have/need less filtering because the diode rectifiers send in a quicker more powerful jolt that needs a heavier Twin style cap array.
Dsl100 and a bugera 1990 both have it. I always thought it was critical to use it.
Definitely not critical. But it won’t hurt anything one way or the other.
Great video! Thanks!
I always warm up my amps on standby to reduce plate oxidation on the power tubes. warming it up without it causes the plates to try pulling in electrons that aren't there yet, causing oxidation. With the rectifier being way before the standby switch, I don't under stand how you could hurt it.
Thanks for this Dr Z. Basically there is no solid reason for a standby switch. All the reasons for maybe needing one are easily dealt with by another method. I read that the reason Leo Fender used them was because of the limited values of filter caps at that time. The current at startup easily charged the caps and thus full B+ was applied to the tubes before they had heated up. So the standby switch allowed the tubes to heat up before B+ was supplied to the tube. With larger caps, the inrush is soaked up so the rise in B+ is slower, giving time for the tubes to heat up. Therefore no standby needed. With solid state rectifiers and large caps there is no need for a standby switch. So if you are building an exact copy of an early Fender tube amp a standby could be added. Maybe. Many early amps did not. The RCA manual does not even mention standby for receiving amplifiers…it states they are only for high power transmission amplifiers.
great channel!
Dear doctor... will you ever make a version of the Antidote with two foot switchable channels? And is it possible to order an Antidote with an FX loop added? Love your videos. You seem like a great human being. I wish Z amps all of the success in the world. Your work ethic and knowledge is truly admirable.
Is it just me or does 30 Dr Z watts of EL84 power sound and feel much louder than 30 watts of 6L6 power from competing amp companies? Is it just Z magic or is it the tubes? #ama
A great question, and we have a pretty good answer for this, I will forward this to dr.z.
Oh man i love yous guys amps , im in.....and i want to know
Watched the whole video and still don't know what the standby switch does that the power switch doesn't
It turns the high voltage on and off. The power switch turns the power to the filaments on
I have my amp unplugged. It is a Fender Reverb Deluxe. When I want to play, I plug it then turn the Power Switch on then I wait like 5 minutes and turn the Standby on making the amp to start working and I can play. When I turn it off I go first to standby, switch it off then I turn the power off. Is that procedure correct? Don I need to use the standby to play at all? Thanks.
My amp is valves.
@@tt-du6vc watch the video
Is there a proper way to turn off a tube amp that has a standby switch?
Standby on or off, does not really matter how you power down the amp (unless you are looking to discharge the filter caps).
I use the switches together. Both on or both off. I don’t stand by
A guitar or bass player actually asked this question?
This question is asked nearly constantly.
You don't need one....it was carried over from the radio world lol.....and besides you don't want more things in that path trying to pull a bunch.
But he says that they protect the tubes in an amp that has a solid state rectifier. Old radios didn't have solid state rectifiers.
@@johnsimms3957 well that was the cathode stripping theory....running the shit high is hard on it anyways. And yeah it's hard to blow those Diodes.
turn the tuner on your pedalboard on....awesome mute switch
Who knew the stand by switch was so controversial.
Please Stand By
Strange to find such false info here. A standby switch was about the cathode follower and EQ and the high voltage on the cathode, not about servicing.
A cathode follower is a part of the preamp section and there is no high voltage on a cathode follower. High voltage in the preamp is typically found on the plate. The stand by switch turns off high voltage from the power supply to the positive rail, which is useful during maintenance, though not always necessary. The cathode of most tube circuits is comparatively negative, or close to zero voltage. It's strange to find a video with thousands of views from tube amp aficionados across the world, and it's only you who seems to know the correct answer.
My amp doesn't have a standby switch. I just don't plug my guitar in until I'm ready to play. Simple. 🔌🎸🇦🇺
So basically it kills the power so the repairman doesn’t get electrocuted. I guess just shutting the amp off with the power switch is too complicated 🙄
The standby switch is completely unnecessary. Don't use it - just turn off the amp or turn down the volume. It does nothing to protect the tubes and it is not a "mute switch" - that is completely different electronically.
From an end user perspective, this is arguably true. However it is useful from the technicians perspective.
@@DrZAmplification That was more true in the old tweed amps that Fender first put them in. Not really true any longer as the capacitor components that Leo was trying to protect are not that expensive today. The standby was primarily to protect the cheaper capacitors he put in the amps as it was cheaper than putting in larger capacitors at that time. The reality is that amp manufacturers aren't concern about amp techs and they could save their customers money by eliminating the switch.
@@DanielBobke You would save them approximately $1.50 in parts/ labor.
@@DrZAmplification But you would save end users of the amp much more than that from repairs on an unnecessary component that can break. The only reason is there on most modern amps is because amp buyers expect it to be there and don't realize it is not needed.
Fireworks and killed the damn xformer lol
no
Before asking silly questions, you should learn before how tube amplifiers work!
Paul Kasper I see. So you never ask questions, then. What a fool.
Before asking questions,.... you should already know the answer. Problem solved.
Barium building up is only in super high power (10,000 watt and more) transmitter tubes, not a 100 watt guitar amp.