Ah, this little AC15CC isn't a bad amp. None of these issues are crippling. Can easily be made fantastic, but it's reliable and sounds pretty good as-is, aside from the Wharfedale speaker.
First let me say thank you, this video convinced me to buy a AC15cc1 on the used market. Like the video says its very shrilling and will take your head off. I had an extra Celestine greenback and tried that first. The greenback made a huge difference but I wanted to try the R23 mod. I removed the resistor. Then wired in a 250k pot to an open spot on the back between the footswitch and fuse, and let me tell you this thing rocks now. I play small venues and have really enjoyed using this amp. A bluesbreaker and a hint of delay is all I use on it. Thank you so much for sharing your knowledge on this. I'm going to binge watch the rest of your channel to see other ideas I can get.
What do you mean by adding a pot? DId you add a tone cut by doing this? Did you replace the bright cap WITH a pot essentially making a "bright knob" instead?
@@lorenzweissel6893 hey man. At 17:55 resistor 23 is taking the place of a high cut. I tried different resistors there but I found that even having more or less people in a room changes the way we sound. Drummer plays louder, etc. By putting a potentiometer in it adds a high cut. I'm able to adjust and cut through the mix. So I put the high capacitor back in and just use the pot.
At 11:00, the leaf-spring shorting contacts in the input jack can be cleaned with thin, fine sandpaper or a pencil eraser carved into a thin chisel-edge or wedge shape, similar to how Lyle here cleaned some old Fender input jacks, in another video. My experience has been that mechanical polishing of the connections is more effective long-term than spraying them with contact cleaner. Also, adding a star washer before remounting the jack to the faceplate would be a good idea, *if* the threaded section on the jack is long enough to allow it. (Edit: Lyle said, in an answer to another commenter, that adding a star washer would likely break the jack or the nut; but perhaps the metal around the chassis-mounting hole for the jack could/ be buffed and polished, especially if it's got paint or anodizing on the inside of the chassis). By the way, these types of modern molded-plastic input jacks often have enough slop and play in the slots where the terminals are sitting that the terminals tend to push up and out a little when the jack is inserted into/onto the board prior to soldering; heating the solder joint for each bent-over contact and pushing the contacts down towards the board will often cause them to seat a little lower (perhaps with a click or a "ping") and slightly increase the contact pressure to what Lyle refers to as the "normal" grounding contacts.
I just got one of these and I could not believe the amount of treble it had. Thank you for explaining that tone circuit. Can I just install a potentiometer where those resistors live?
Thank you, I've had the urge to get a Fender deluxe reverb RI 68 for a while and your videos helped me postpone the purchase. I whish you were closer so I could get you to do all the corrections and mods. As it is I am quite happy with my VOX tb18c1 (Tony Bruno) (somewhat Fenderish sound, I guess) but I now wonder what the hidden issues are with that amp. Did you work on any, are there some things I should be careful about?
Hey something to address: what effect does other equipment in the vicinity of the amp, and what the amp is plugged in next to, have on the noise floor. I'm using a new hot rod deluxe iv. Also not an electrician so pls dumb down any answers.
Have you worked on any of Vox's Night Train amps ? Im interested in the 15watt Version 1 or Version 2 that has reverb onboard and a fx loop. But im not sure how the reliability is on them. An AC15 head even used is more $, but if thats built better than the Night Trains, im gonna go with that. But the size of the Night Train series is perfect for what I would be doing.
Great video! Can I ask you something? My ac15cc1 slowly started getting some low hum noise (at 100hz precisely), even with no input signal and volume pot at zero, and i was told to replace the valves first so i'm looking on to it. I know that i need two paired EL84, but what about the two 12ax7? do these 2 have to be "paired" too? do i need a "balanced" one? As you can see i have no grasp on electronics lol. Thanks in advance!
Thanks for sharing your knowledge. I have the ccx1 model with the blue anilco speaker since a few years. I like the 1channel only concept on amps like that. I haven’t met any problems yet with this combo but It’s very true that the quality of some basic parts like input jack, power switch, AC plug seems quite poor. Or As you mentioned the loose tubes sockets.... What’s your opinion on the potentiometers quality? Thanks again for your time and your videos
Thanks! The pots are ok. Not great, but better than some Marshall and others use on much more expensive amps. And Vox uses these same 16mm Alphas in their HW models. I upgrade them in that model.
I feel like every tech should start inserting plastic sleeves that contain their notes on what they did so the next tech that comes along could see their logic and also know what to expect. Why is that not a common courtesy?
Many Technicians will if you ask them. If they won’t you can find a different Tech. That is the main reason I’ve stuck my the same amp Tech for over 30 years. Even though I moved far away I now have to ship my amplifiers to him. Very expensive added cost but worth the piece of mind.
The rules to do with not easily accessing tubes is EU. The non leaded solder is also EU. I live in the UK and it has actually become easier to get leaded solder now because people realised quickly how bad the non leaded solder is to work with.
Thanks sir for steering me away from the modern Supro. I bought the AC15-CC1 from Sam Ash $542.00 delivered. I wanted the C1, they sent me the CC1 but it looks beautiful and new so I'll keep it. What should be done to sent it up for British Blues, Dirty Blues and Blues Rock?
I just picked up a used VOX AC15-C1 112 Combo and it seems to be very "touchy" with LOUD Popping noises whenever I flip a switch on guitar, or when I flip from standby mode to ON. I already installed all new JJ tubes and it didn't help much. I already checked the boards, and everything looks very clean, no burnt or oozing resistors, etc.. Any suggestions would be appreciated.
Hello and many thanks for your excellent vids. I've only just discovered your channel. I was drawn to your series on Fender reissue black face amps as I have 65 Twin. Fortunately it's been pretty well behaved. This vid prompted me me to seek your opinion please. I have a Vox AC15 hand wired model (made in Vietnam) with an alnico blue speaker and it is actually pretty well made from what I see however the circuit is not true to the original AC15. It has a 'redundant' hot switch which I never use and even in normal mode it sounds very brittle and harsh at the top end. I've read similar complaints from other owners. Is there a simple mod I can have done that will make sound more like an authentic Vox in the upper frequencies?! Cheers from New Zealand
Thanks. The HW is a hard sounding amp. It's over filtered and the ceramic caps they used don't sound that great. The combination makes it a little unpleasant. Some HWs also have the output grid stoppers mounted on the board rather than at the tube sockets, which can make things worse. A good tech can fix this but it's not "simple" for the average owner.
@@PsionicAudio Many thanks. Your input is appreciated. I will take it to a tech sometime soon. There are very few guys around these days (near where I live anyway) who still do tube amp stuff but I do know a couple of guys who might be able to help. Cheers
Whoa whoa can you tell me what you did again with that resistor. I have this amp and I love it but I want to make it sound better too. Any advice. Dave from Australia. Thanks for the video.
@@PsionicAudio ok I like that thanks mate. Yeah I find I have to turn guitar tone down quite a bit to lose a bit of that top end. Thanks for your time.
The Cut control (a pot/knob in most ACxx amps, just a resistor in the AC15CC) affects the high end response of the EL84s. The real answer is chapter length, but for now let me just say it's a different level of control and that having the lowered resistance here makes the Treble much more useful as you can get airy response without harsh high end.
I've got one of these. Lately it's gone super weak......you have to absolutely crank the volume knobs to get it sensibly loud. It used to rock the house! Not anymore. Any thoughts?
Is this a real Vox? I was looking at the schematic and it only has two tube gain stages before going into a plate driven tonestack with lots of IC’s and lnd150 for the reverb and tremolo circuit before going to phase inverter tube. Seems like this amplifier in the preamp doesn’t have anything over the AC10C1. That at least has a cathode driven tonestack. And 4 gain stages including the lnd150 stages. Any thoughts? Seems way way way different from the AC30cc2 model
It’s very different than the 30CC. It’s still much better than the 10C due to the headroom of the SS stages. The 10C is criminally clamped by that 5V unipolar supply. But I don’t recommend the AC15CC as the AC15C is so much better.
@@PsionicAudio wow!! I will take the pcb mounted tube sockets and mdf cabinet construction of the 15c1 over the 15cc1 any day!! Still very intrigued by the AC30cc2 though over the AC30c2
The C1 and C2 are amps where you should use standby as the rectification is solid state (though it emulates a tube well) and the preamp filter caps cannot handle the full unloaded B+.
Man, this channel has scared me away from just about every amp I've been considering lately. lol
Ah, this little AC15CC isn't a bad amp. None of these issues are crippling. Can easily be made fantastic, but it's reliable and sounds pretty good as-is, aside from the Wharfedale speaker.
@@PsionicAudio I have the wharfdale speaker in mine I like it but could you be more specific about what is wrong with the speaker?
@@gravidium listen with good speakers or headphones.
ua-cam.com/video/RviMmnmkDCk/v-deo.html
@theonetrueolaf , perhaps Brad's channel might scare people for decidedly different reasons? 🤔
@@goodun2974 Brad tells the reality of the government and that *should scare you.
ALL amp repairs you do are enthralling as heck!
Absolutely brilliant video. Great to see the separate valve bases in this amp. Pretty solid.
Ghhoixc guy vu
I greatly enjoy your videos, don’t be afraid to go long
Good to see that others also struggle with the same awkward issues on these modern amps....
First let me say thank you, this video convinced me to buy a AC15cc1 on the used market. Like the video says its very shrilling and will take your head off. I had an extra Celestine greenback and tried that first. The greenback made a huge difference but I wanted to try the R23 mod. I removed the resistor. Then wired in a 250k pot to an open spot on the back between the footswitch and fuse, and let me tell you this thing rocks now. I play small venues and have really enjoyed using this amp. A bluesbreaker and a hint of delay is all I use on it. Thank you so much for sharing your knowledge on this. I'm going to binge watch the rest of your channel to see other ideas I can get.
What do you mean by adding a pot? DId you add a tone cut by doing this? Did you replace the bright cap WITH a pot essentially making a "bright knob" instead?
@@lorenzweissel6893 hey man. At 17:55 resistor 23 is taking the place of a high cut. I tried different resistors there but I found that even having more or less people in a room changes the way we sound. Drummer plays louder, etc. By putting a potentiometer in it adds a high cut. I'm able to adjust and cut through the mix. So I put the high capacitor back in and just use the pot.
I love your videos! and the diag steps are great for a learning like me!!!!
This was great, thank you.
I subscribe today and am looking forward to more of your content.
Fascinating videos. Thanks
Another awesome video.. cheers mate :)
At 11:00, the leaf-spring shorting contacts in the input jack can be cleaned with thin, fine sandpaper or a pencil eraser carved into a thin chisel-edge or wedge shape, similar to how Lyle here cleaned some old Fender input jacks, in another video. My experience has been that mechanical polishing of the connections is more effective long-term than spraying them with contact cleaner. Also, adding a star washer before remounting the jack to the faceplate would be a good idea, *if* the threaded section on the jack is long enough to allow it. (Edit: Lyle said, in an answer to another commenter, that adding a star washer would likely break the jack or the nut; but perhaps the metal around the chassis-mounting hole for the jack could/ be buffed and polished, especially if it's got paint or anodizing on the inside of the chassis). By the way, these types of modern molded-plastic input jacks often have enough slop and play in the slots where the terminals are sitting that the terminals tend to push up and out a little when the jack is inserted into/onto the board prior to soldering; heating the solder joint for each bent-over contact and pushing the contacts down towards the board will often cause them to seat a little lower (perhaps with a click or a "ping") and slightly increase the contact pressure to what Lyle refers to as the "normal" grounding contacts.
No, you don't want a toothed washer on a plastic Cliff style jack. I'll be showing the proper fix in Part 2.
I just got one of these and I could not believe the amount of treble it had. Thank you for explaining that tone circuit. Can I just install a potentiometer where those resistors live?
Thank you, I've had the urge to get a Fender deluxe reverb RI 68 for a while and your videos helped me postpone the purchase. I whish you were closer so I could get you to do all the corrections and mods. As it is I am quite happy with my VOX tb18c1 (Tony Bruno) (somewhat Fenderish sound, I guess) but I now wonder what the hidden issues are with that amp. Did you work on any, are there some things I should be careful about?
Exactly. You learn by burn.
Hey something to address: what effect does other equipment in the vicinity of the amp, and what the amp is plugged in next to, have on the noise floor. I'm using a new hot rod deluxe iv. Also not an electrician so pls dumb down any answers.
Have you worked on any of Vox's Night Train amps ? Im interested in the 15watt Version 1 or Version 2 that has reverb onboard and a fx loop. But im not sure how the reliability is on them. An AC15 head even used is more $, but if thats built better than the Night Trains, im gonna go with that. But the size of the Night Train series is perfect for what I would be doing.
Great video! Can I ask you something?
My ac15cc1 slowly started getting some low hum noise (at 100hz precisely), even with no input signal and volume pot at zero, and i was told to replace the valves first so i'm looking on to it. I know that i need two paired EL84, but what about the two 12ax7? do these 2 have to be "paired" too? do i need a "balanced" one? As you can see i have no grasp on electronics lol.
Thanks in advance!
Thanks for sharing your knowledge.
I have the ccx1 model with the blue anilco speaker since a few years. I like the 1channel only concept on amps like that. I haven’t met any problems yet with this combo but It’s very true that the quality of some basic parts like input jack, power switch, AC plug seems quite poor.
Or As you mentioned the loose tubes sockets....
What’s your opinion on the potentiometers quality?
Thanks again for your time and your videos
Thanks!
The pots are ok. Not great, but better than some Marshall and others use on much more expensive amps. And Vox uses these same 16mm Alphas in their HW models. I upgrade them in that model.
It is very hard to buy a good amp. Do you have experience with the Tone King Gremlin combo?
I feel like every tech should start inserting plastic sleeves that contain their notes on what they did so the next tech that comes along could see their logic and also know what to expect. Why is that not a common courtesy?
Many Technicians will if you ask them. If they won’t you can find a different Tech.
That is the main reason I’ve stuck my the same amp Tech for over 30 years. Even though I moved far away I now have to ship my amplifiers to him. Very expensive added cost but worth the piece of mind.
The rules to do with not easily accessing tubes is EU. The non leaded solder is also EU. I live in the UK and it has actually become easier to get leaded solder now because people realised quickly how bad the non leaded solder is to work with.
Is there some type of gel or protective anti-corrosion compound you can put on a connection like that jack, so it doesn't rust in the future?
Craig d5 deoxit
Thanks sir for steering me away from the modern Supro. I bought the AC15-CC1 from Sam Ash $542.00 delivered. I wanted the C1, they sent me the CC1 but it looks beautiful and new so I'll keep it. What should be done to sent it up for British Blues, Dirty Blues and Blues Rock?
I'm not a huge fan of the AC15CC but see my video today on the AC15TBX. In it I tell how to de-icepick the CC too.
I just picked up a used VOX AC15-C1 112 Combo and it seems to be very "touchy" with LOUD Popping noises whenever I flip a switch on guitar, or when I flip from standby mode to ON. I already installed all new JJ tubes and it didn't help much. I already checked the boards, and everything looks very clean, no burnt or oozing resistors, etc.. Any suggestions would be appreciated.
All I can suggest from a distance is make sure the input jacks are tight.
Thank you, I'll check that out.@@PsionicAudio
Why not a(n) internal tooth washer for that input jack?
Because it would break the plastic jack and/or nut.
Hello and many thanks for your excellent vids. I've only just discovered your channel. I was drawn to your series on Fender reissue black face amps as I have 65 Twin. Fortunately it's been pretty well behaved. This vid prompted me me to seek your opinion please. I have a Vox AC15 hand wired model (made in Vietnam) with an alnico blue speaker and it is actually pretty well made from what I see however the circuit is not true to the original AC15. It has a 'redundant' hot switch which I never use and even in normal mode it sounds very brittle and harsh at the top end. I've read similar complaints from other owners. Is there a simple mod I can have done that will make sound more like an authentic Vox in the upper frequencies?! Cheers from New Zealand
Thanks. The HW is a hard sounding amp. It's over filtered and the ceramic caps they used don't sound that great. The combination makes it a little unpleasant. Some HWs also have the output grid stoppers mounted on the board rather than at the tube sockets, which can make things worse.
A good tech can fix this but it's not "simple" for the average owner.
@@PsionicAudio Many thanks. Your input is appreciated. I will take it to a tech sometime soon. There are very few guys around these days (near where I live anyway) who still do tube amp stuff but I do know a couple of guys who might be able to help. Cheers
Whoa whoa can you tell me what you did again with that resistor. I have this amp and I love it but I want to make it sound better too. Any advice. Dave from Australia. Thanks for the video.
I put a 68K in parallel with the existing 220K, gives a value of about 50K. Takes the icepick out of the amp.
@@PsionicAudio ok I like that thanks mate. Yeah I find I have to turn guitar tone down quite a bit to lose a bit of that top end. Thanks for your time.
One more question why add a resistor and not just back off the treble? What is the difference?
The Cut control (a pot/knob in most ACxx amps, just a resistor in the AC15CC) affects the high end response of the EL84s.
The real answer is chapter length, but for now let me just say it's a different level of control and that having the lowered resistance here makes the Treble much more useful as you can get airy response without harsh high end.
@@PsionicAudio got it!
I've got one of these. Lately it's gone super weak......you have to absolutely crank the volume knobs to get it sensibly loud. It used to rock the house! Not anymore. Any thoughts?
Most likely just a tube.
@@PsionicAudio looks like I've actually got a C1 not a CC1. That's not at all confusing is it?? haha. Thanks!
Is this a real Vox? I was looking at the schematic and it only has two tube gain stages before going into a plate driven tonestack with lots of IC’s and lnd150 for the reverb and tremolo circuit before going to phase inverter tube. Seems like this amplifier in the preamp doesn’t have anything over the AC10C1. That at least has a cathode driven tonestack. And 4 gain stages including the lnd150 stages. Any thoughts? Seems way way way different from the AC30cc2 model
It’s very different than the 30CC. It’s still much better than the 10C due to the headroom of the SS stages. The 10C is criminally clamped by that 5V unipolar supply.
But I don’t recommend the AC15CC as the AC15C is so much better.
@@PsionicAudio wow!! I will take the pcb mounted tube sockets and mdf cabinet construction of the 15c1 over the 15cc1 any day!! Still very intrigued by the AC30cc2 though over the AC30c2
re using standby is this true for the C1? heard different views
The C1 and C2 are amps where you should use standby as the rectification is solid state (though it emulates a tube well) and the preamp filter caps cannot handle the full unloaded B+.
@@PsionicAudio great thanks
Please share the part number for the replacement input jack. Those plastic pieces of trash should be outlawed.
Why no audio, reading transcript is a pain. Wtf later can't subscribe to a mute.
The audio on the video is fine. Check your settings.