Why don't amplifiers have clipping protection?
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- Опубліковано 28 вер 2024
- We understand that amplifier clipping can damage speaker drivers so why don't amp manufacturers protect from this happening? Have a question you want to ask Paul? www.psaudio.com...
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I absolutely love playing your videos at 1.75x speed while im driving. Can hear more topics during my drive and it keeps up with the pace of my driving.
Nad amps have clipping protection
Yes they do and it has saved my friends speakers more than once, we all probably know that person that just have to turn up the volume on the amplifier when its all ready loud 🔊
I leave mine off - if I were to have a party - that thing goes on!
I have NAD C352 which has soft clipping future, BTW I never ran my amp into clipping so cant say how that sounds.
Yes they do ,over my 4 decades in HiFi I've ran across very few amps with a quality soft clip circuitry & my 1980s NAD amps had a great circuit ,I also don't understand high end manufacturers killing off tone controls and especially the loudness countour feature ,I find the loudness feature on my vintage early 90s McIntosh C-38 to be the most valuable feature for less than perfect recordings at nominal listening levels.
I have a NAD c-370 amp and it does have "soft" clipping. I do not have it turned on. I'm driving a 4 ohm load and have never had my amp run out of steam.
Loud in general is not good for speakers, whether or not the amplifier is clipping. If the tweeters get hotter faster than they can dissipate the heat, it will cook the ferrofluid on the coils. This will vary from speaker to speaker so much it's impossible to generalize.
The best thing is to keep a decibel meter around and not let the music get above 80-85 decibels consistently. Anything higher is not a safe listening volume, anyways.
If you can a little bit about sound and amplifiers then you know that you should not turn volume so amplifies clips!
You also need to protect your ears! without them, music is not fun.
NAD amplifiers almost always have soft clipping you can turn off with a switch.
Paul could you speak up a bit. Some thing about needing a bigger amp every few years?
5:24 nice :)
For parties you can get a cheap, high current pro amplifier. Most of them have clipping protection, and they will get loud. But they are not made for critical listening. They have more distortions and noise than high end hifi amplifiers.
@Psycho Snake Those specs tells that you could use it for party. Sure. But I don't want anything cervin Vega stuff, they are focusing on power, not refinement.
@blackened 1 I know that there are some pro amplifiers that are made particularly for critical studio use. But most are not. But those good amplifiers doesn't come cheap.... in the $200 to $600 range there are many powerful pro amplifiers, but most of them are made for stage use, not critical listening use.
@blackened 1 It is similar to say that studio monitors are not good for listening to music, but some of them are exception to that. But most of them are not good for listening in the living room.
@blackened 1 I guess that the FTX 2000 sounds much better than the new amplifiers made from Ashly. Simply because it use A/B amplification instead of class D, and it is rather lower power, but more quality per watt instead.
@blackened 1 Yes I saw that in the specs, but it's discontinued. But there are not many professional studio monitors that are passive left. So the marked for amplifiers for studio use in critical listening conditions is diminishing. There are some very good ones, but they are in the same price range as good hifi amplifiers.
one of the amps i have owned was a nad d3020, nad have clipping protection the commenter says here, mine just went into protect mode if i played too loud, maybe i was not clipping the amp but hit temp limit or something, but it sure sounded fine until it shut itself off. very loud for sure.
um... McIntosh amos DO have clipping protection!
Don't some amp's have LED's that indicate clipping? An LED is essentially a diode and seems like it would work the same way.
NADs have. They call it "Soft clipping".
Mr. Wizard vibe, anyone?
ADCOM GFA 555 that i use has lights that come on when you approach 1% THD, I can make them blink with the volume about 4 oclock and my hands over my ears when they are powering my MMG Magnepan speakers
Get a McIntosh amp and never clip .
I think that to answer the first thing that comes to the mind of a novice full of adsurd dilemmas (as I was too when I started in hi-fi) is a waste of time. I could seem rude to some but I blame my poor English, far from my intention.
If we audiophiles care our equipment and our ears and knowing that rarely is needed more than ten watts in average at an apartment to blast, well...
Two brands comes to my mind when some sort of soft clipping is used, NAD and McIntosh but almost all amplifier builders use some SOA guard circuit to protect final transistors. I believe the differences are in which stage the protection circuit is put. When it is in the input or voltage amp stages is a soft clipping and when it's in the power stage it's named differently.
My vintage yamaha has a button for it.
Just do it like we say in the USA. "Go big and stay home!"
It's go big, or stay home.
go hard or go home?
Permanent hearing damage cat fish? Lol
Are you a child? Have you never watched movies?
Look after your ears dude!! I Recently had a mini health scare with hearing loss. Thankfully it returned to normal. During the recovery period I had no spacial awareness at all. Scary stuff for a audiophile.
Karl Todd scary stuff for anyone
I can relate right now. I have fluid inside my right ear that has been causing me problems hearing out of that ear, and my spacial awareness has changed. I hope this is temporary.
I wish that I could get that annoying ringing in my ears to go away. Its an every day nightmare.
@@randomtube8226 I had that ringing in my ears for a long time. I tried a lot of remedies until I tried Ground "turmeric" or Curcuma. I buy mine at Fooddepot or Ingles Markets, It is cheap at about 2 to 3 dollars, 2 oz. In my case it took at least 3 months to hear a difference, please be patient.
During the early 1990s, virtually all entry level NAD amps have clipping protection, but audiobuddies of mine who own such amps say that the amp souns much more open when the clipping protection circuit is turned off - even at moderately loud listeming levels - i.e. 96 dB SPL with a 90 dB per watt / 1 meter sensitive loudspeakers.
No. Hafler did not have a clipping "protector". It was McIntosh. But Hafler had an experimental circuit that demonstrated the presence of distortion.
Get a bigger amplifier! Double your power.ha just heard paul say the same thing!
A zener or any diode "clipper" is just that, a clipper. The only difference is you are not stressing the amp but you are just moving the clipping to the amp input. You still hear a nasty clipped signal and it's still bad for tweeters. The way McIntosh did it was a true clipping prevention system. They put a Cad cell (same thing inside a lights on at dusk switch) across the input with LEDS or lamps fed from the speaker terminals shining onto the cad cell. As the voltage approached the amps clipping region and the lamp brightened, the cad cell lowered in resistance and pulled down the input voltage. Thus no clipping took place. But this is not without faults. What you have here is a dynamic range compressor and is in fact how early analog compressors worked although they use a much more linear VCA now days. You can also reverse the process and use the feedback increase dynamic range such as the famous DBX processors of the 70s. And there were also several magazine construction articles at the time for making your own range expander/compressor with LEDs and cad cells from Radio Shack. I must agree the best approach is to just stay out of the clipping region all together. Shouldn't be a problem these days with typical amplifier power levels.
Old NAD amps had a “soft clipping” circuit.
To be honest , a clipping protection circuit really do not change sound quality
at all when you are below the set max limit .
It is when you have a higher voltage input and it start ' doing it's job ' you will
hear a change BUT then you are already way too high on the voltage anyway
so if turn down to just below it then NO DIFFERENCE AT ALL .
It is simply just a MYTH like so many other so-called High-Fi myths .
There is even clipping protection built in to the poweramp stage of professional
Amplifiers that monitor the OUTPUT signal and lower the input if max is reached .
Again at normal ( with normal I mean NOT going over the limit ) use you wont
notice at all this is present .
But when you are going over the max limit then it start doing its job and the
tiny tiny delay from the too high and until it is lowered is what you hear and it
have a compressor like effect on the sound .
But after all , driving the amplifier above what it was built to handle is anyway
bad and without protection ,well it will clip because the powersupply can no
longer deliver high enough voltage to reach the top / bottom of the wave .
The limit of the power supplys Voltage and Ampere is reached and the top and
bottom of the wave is simply flat like DC and ,,,,,,, well it's clipping as we say .
This is bad for speakers because the membrane / cone is pushed out longer
time and thus a DC like voltage is constant for that small amount of time .
What happen is the coil can not dissipate the heat fast enough and by
staying ' hot ' longer the coil burns .
Unders normal load at same power / volume BUT with a power supply
there can deliver high enough voltage to NOT clip then the cone / coil will
move back and fourth in a NON interrupted motion and NOT stay pushed
out / in at max at that ' longer time ' thus the variation of voltage combined
with the Un interrupted motion will let the coil cool down a bit in between
the voltage spikes and , well doesn't burn the coil .
This is also why smaller amplifiers are more dangerous to a even big speaker
than a big amplifier is to a little speaker.
It is more likely a 20 watt amplifier is going to blow a 100 watt speaker
than a 200 watt amplifier is going to blow the same speaker .
Simply because of the bigge power supply .
And Of course we may NOT forget that DISTORTION is extremely important also .
Bigger amplifiers also tend to have less distortion too and distortion is also
a major speaker killer .
In professional use they for shure have clipping protection on and for those
amplifiers without such then compressor / limitier can be used to protect
the amplifier / speakers and again those
DOES NOT CHANGE THE SOUND QUALITY AT ALL .
As long as you are BELOW the CLIPPING POINT .
It is a MYTH .
Edit - As an experient , If you was to built clipping protection into amplifiers in
the series of amps BUT never told anybody about it .
NOBODY WOULD EVER KNOW IT OR NOTICE ANYTHING AT ALL .
But those who doesn't know how to protect their speakers is less likely to blow them .
MCintosh as you already mentioned have used this for decades and is highly
respected and deliver exelent sound quality so , REALLY no , it doesn't change
anything in the sound at all otherwise they wouldn't use it .
Sorry for the typos if any , im on coffe right now .
McIntosh has had that since forever. It works really well, though I'm not a Mac amp fan for other reasons.
It's called 'Power Guard'...and no, they haven't had it "since forever"
@@immovableobjectify Yes and it was developed and implemented in the 60s. So yes they basically had it forever.
Many amplifiers have power-limiting circuitry which serves to prevent sustained clipping, as well as keeping woofers from overheating. Commercial amplifiers with DSP such as the Crown XLS series, my old Dynaco Stereo 400, and many McIntosh models have the feature.
Placing a fixed clamp at the input (by the way, the Zeners need to be in Series, not Parallel) is an undesirable solution as it will consistently create distortion at voltage levels which are near but still below the clipping point. Although this is functionally the same as the method NAD uses to implement their soft-clipping feature.
Is this similar to speaker protection?
To protect the audio amplifier and the
loudspeakers during start-up sequence when the amplifier output might exhibit DC voltage, and to protect the
loudspeakers in the unlikely event of an amplifier power stage failure, where DC component would damage the
speaker voice coil.
Could you use speakers that can handle much more power than the amp can provide? For example, hooking up 500 watt speakers to a 100 watt amp? It seems like having over-rated speakers would give you lots of headroom so you can't blow them even at the loudest volume. As long as the impedance is correct it should be okay.
I doubt it was so much that he was worried about himself causing the clipping as much as he was worried about a guest in his home walking over and just cranking it up. You can't leave idiots unsupervised. :-)
I like the limiters that use a led and LDR, like: sound.whsites.net/project53.htm
They reduce the volume whenever the output voltage is above a certain level, without causing much distortion.
Just wanted to add that running too small of an amp loud damages more speakers than running a bigger amp loud, a 20 watt per channel amp can damage tweeters in a set of 100 watt speakers run into clipping ;)
Totally true , the Amplifier start clipping when it can't deliver enough voltage .
Bigger Amplifiers have bigger powersupply so can deliver higher voltage and
of course more Amperes too .
If your amp is actually powerful enough for the speakers you are using they won't get damaged by playing them loud if you are getting clipping you source is where the problem is
couldnt an auto mute circuit be designed so when the input voltage gets to a certain level it either completely mutes at the input circuitry or trips the overload and startup protection relay?
the relay i am talking about is when you turn on the amplifier a second or 2 later you hear a click.
i assume that relay is so you dont hear the thump and hum when the system is turned on and charging the large capacitors that are connected close to the speakers.
of course i think the relay is a last resort protection as it disconnects the speakers while the unit is on witch is something i have heard is bad as you are taking the amplifier from full load to no load back to full load in a split second so maybe using the mute circuitry may be safer.
you could just turn down your input source like if you are streaming from your ipod or computer you could turn that down so you shouldnt clip and only use the loudness of the amplifier to fill the room.
not just ears but loud parties can draw the police as there are noise laws in some places so if you are in a place near other neighbors you could get complaints..
copyrights could be another problem you could get copyright notices due to public performance.
I don’t have a reason ever to play movies or music so loud that I’d clip my amp.
No need for clipping crap if the amp is more than powerful enough👌
Shit, crank it loud or go home to your mama's house!
Crown amp has clipping protection
Easy, just monitor both channels with an oscilloscope!
1:20 - The Dynaco Stereo 120 had such a circuit to limit power longer than a certain interval.
Dimitri check your ears
All you really need is your ears
I have to agree with Paul here 100%...!
Though you can get POWER limiters ( which just trip a relay ) at a certain RMS power level ... and others that provide current limiting to the power supply ( bit like foldback ) .. best think is, like Paul just said get an amp that won't clip and speakers that can handle all its capabilities with EASE... let your ears be the judge
Is that was NAD uses?
McIntosh does!
Mine does
I have a Realistic APM-200 peak and RMS watt meter hooked up to my tube amp system currently, but have had it for years. Best investment I ever made, saved many speakers because your ear is not a good judge of how loud it really is, especially is alcohol and a party is involved. The old Adcom GFA series amps had instantaneous distortion alert yellow led's on the front which were helpful. Many large amps of the past which I have had owned had large VU meters on the front, Kenwood 700M, Onkyo Intergra M-504. Rule of thumb I have used is never use all of your amplifiers power, if you need more than 50% of it's rated power that only leaves you 3db of dymanic headroom. You need a bigger amp like Paul says. Get a hand held sound level meter and pay attention to your listening levels. Safe levels for listening are 85db or less is safe. 95db is safe for 1 hour, 100db for 15 minutes. Of course those are for constant volume levels and music is dymamic so transient sounds that last for fractions of a second might peak higher. Kind of like how you can move you finger through the flame of a candle quickly, but don't hold it there. Of course 130db or higher can cause permanent hearing loss even for short duration, like a gun shot or thunder.
NAD has been using that circuit for years with a switch to turn it off. John Bowers used the "a-poc " circuit in some of the Matrix speakers. Bottom line is, don't be an animal with your stereo.
There is no need for clipping protection on amplifiers. Just need to make them ideoit proof. You got the people out there that not only crankes the volume up all the way. But also all of the settings.
Nad amps do
A few decades ago there was an article that showed how to soft clip and amp by putting a diode in the negative feedback loop. I suspect that would feed back opposite polarity odd order harmonics to reduce those and make the output clip with even order harmonics, which tube amps do naturally. The result is a curved, not sharp clip. Interestingly, odd order harmonics tend to make heat. Don't quite understand he physics behind that but according to "Harmonics" by Mark Waller, this is the cause of many of the power woes with computers and why line filtering and conditioning is so important. Clipping the sound at the input may not cause the power amp to reach clipping, but may make the sound kind of nasty. Ever hear an over driven signal into a preamp? Blech!
Problem is actually, tube clip much earlier than transistors, at the time tube clips, transistors are still working without any distortion. At the time when transistors are clipping, tube has already outputted crap. But that depends on the supply rail and design of course.
My Crowns have it 👍
excellent info. clipping the source signal will clip any amplifier. make sure your source isn't clipping!
I have an older CD of African drum performances, and several of the tracks have heavy clipping. Someone got their gain balancing all wrong in the recording chain.
Capisce ;)
Ho Capito
Apparently my Cambridge cxa80 comes with clipping mode, but it's turned off as default....I haven't looked into how to turn it on, but I don't think I need it anyway.
I have the same amp and it actually turns the volume down automatically if the amp starts clipping which is an awesome feature!
@@behemothinferno yeah, that's what I believe. But I haven't tried it out or even know how to select the feature.
25K Watt amp MMM my subs wanna feel that pulse my house :) the neighbors too! ahhh headroom for days
Gee, friend. That's maxing out a residential 100 amp service. I guess if you really need 160db at 33hz, then ok. That is... going big and staying home! But then again, you do like the dark side!
@advsoft What is the amperage of the circuit supplying the power? 120 volt or 240? Watts = Amps X Volts, perhaps you meant 2.5K watts. That is power draw, not power out, unless you have a zero loss unity gain power amp. I used to laugh at those 100 watt Chinese car audio amps at the flea markets with the 1amp input fuse.
Hi PaulThe Zeners would be in series. The voltage across a Zener in the opposite direction is about .7 volts. So to clip at 2 volts a person would use a 1.3 volt Zener in series with a Zener placed in the opposite direction. The conduction would occur at 1.3 volts for the forward Zener plus .7 volts for the reversed Zener. The problem I see with that idea is the signal is still clipped. Yes, with a R/C network it can be softened. Professional amps have a compressor circuit that kicks in to reduce the amplifier gain as it approaches clipping. I like your approach best though as any of these circuits will affect the sound. I like the idea by Oystein to buy a pro amp for the loud times. When you are listening that loud the loss in quality won't be so obvious and pro amps are cheap new or used.
The classic circuit is two zeners in opposite directions in parallel. One end to ground the other on the input. Anything exceeding the zener's rating gets lopped off.
Sorry Paul, that would leave you with a peak voltage of .7 volts regardless of the Zener rating. I have seen the circuit you described numerous times to protect the input of an i.c. but they used 1N914 or similar. If you look at Klipch's older tweeter protection or the Koss E9 adapter box input protection the zeners are in series cathode to cathode or anode to anode.
@@johnhodgson5313 Ahhh, you have jogged the old memory out of the cobwebs. That's right, those shunts were 1N914 standard diodes. Thank you for clarifying that. I stand corrected.
I have tinnitus but playing music loud is just too much fun. I just have to blast my favourite songs some times full volume.
Good thing I read the comments BEFORE I type a response/comment as others have already said, NAD has soft clipping you can switch in/out if needed. I have a vintage 7240PE, the receiver version of the 3240PE integrated, both can be split into separates with the jumpers removed if desired. they are rated by NAD at 40W, RMS but we all know that's a conservative rating, it's closer to 60W, RMS. However, the amps are high current, but low damping (unfortunate for ported speakers, but are fine for acoustically suspended models) and a video on YT where a guy used a clipping tester and found that these have a lot of headroom, @8 Ohms, about 150W, 6 Ohms, 250W, 4 Ohms, I think 350W, and at 2, yes, 2 Ohms (rare for gear of this caliber), 550W!
In my living room with the first series ADS L810 speakers at 88 sensitivity, I can't run much past 12:00 as it gets LOUD in my room and my turntable begins to hum as oscillations in the low frequencies begins to invade, not good. Tape/CD, not an issue and the amp does NOT compress, but stays clean and does not get all that much louder as the volume is cranked (as a test). So most of the time, I run the amp at best at 10:00 or maybe 11.00 at the absolute most as the oscillations will begin to incur when playing vinyl as I do most of the time.
That said, I agree that best to have more than you'll need and NOT blow your speakers, but ADS also have fuses and thus pop if you try to run them loud with a lot of high frequency energy music first, long before the amp even hits clipping. I've done it, not intentionally so the speakers are not the ultimate rocker speaker, but I don't do a lot of hard rock/heavy metal anyhow.
Here's our BHK amp. Buy one!
I would think that the best approach to speaker protection would be to design power amplifier circuits around individual speakers, so that the amplifier could limit the amount of energy at any particular frequency to levels the speaker could handle. Otherwise, almost any amplifier whose limiters aren't customized to a particular speaker will either be incapable of playing some inputs as loud as the speaker could handle, or would drive the speaker harder than it could handle given other inputs. If one has 50-watt speakers, getting a 700-watt amp may ensure that the speakers don't get destroyed by amplifier clipping, but having the speakers get blown as a consequence of being fed a beautiful clean 600-watt signal isn't any better. And replacing the 50W speakers with 700W speakers so that accidentally switching to an overly-loud source blows your ears instead of the speakers wouldn't be any good either.
At minimum, I would think that any amplifier which has a digitally-controlled gain path should be able to quickly cut the gain if the output power in any particular frequency band exceeds a certain limits that could be customized to the speakers one is using. Having a sudden cut in gain may be distracting if it happened while one was trying to listening to audio at a level near where the system would cut out, but in most cases one would want to have an amp and speakers that could produce a little more volume than one would want to *deliberately* use, so one could set the cutoff a bit beyond that.
Paul, my hearing is already diminished so I have to crank it up to hear it. I'm 69 and worked in a machine shop for 40 years. Yeah I should have used ear protection for the time I spent in a noisy shop but it's too late.
Hey Paul, pro audio power amps include LED's that alert you when the amp is clipping, does the inclusion of this circuit also effect the sound quality, if not why are they not used on domestic amps? Thanks.
Pro amplifiers are not as good sound wise as HiFi amplifiers. But for partying they will do just fine.
@@oysteinsoreide4323 are you sure about that ?? Have you ever done blind testing ? Just curious..
The "clip" lights on most pro amps i.e. Crown's IOC, are indicators that there is something non linear happening in the amp that cannot be corrected by global negative feedback. Clipping, current limiting, slew rate limiting and other things will be indicated. When the negative feed back cannot correct for the problem the input circuit will go from a low gain to a high gain circuit, the increased output of the circuit is detected and turns on the light. As you can see, this requires an amp with lots of gain and lots of negative feedback. Paul will probably tell us why designing an amp this way is not great for high end audio, if we ask him.
@@poserwanabe I have talked with a musician who has much experience with both hifi and professional audio gear. He clearly suggested to me to avoid professional amplifiers for a living room listening experience. He said that the pro amplifiers typically have much power, but lack in refinement and they have noisy fans running.....
@@oysteinsoreide4323 Another hi-fi myth.