On/Off Switch

All this shows the futility of the power cable story. This is not to say that a decent power switch would not be a good thing. However, I would not start tinkering with mains voltage components. A well designed amplifier should have this covered, particularly from a well respected mainstream manufacturer that has a lot to lose.

All this shows nothing more than the futility of cheap power switches. In gear that can be left on all time, you might consider removing the switch, and its associated wiring leads, altogether and use slightly better wiring in the bypass. Many DIY'ers and modders have recommended this. 

If you need the switch in place, consider something like the higher-quality, silver-contact, 2-way toggle switches. Online electrical supply houses often have them. Parts Express might have one or two, I don't know. Also try Goldpoint.

The cheap-@ss sliding, pushbutton or rocker switches in almost everything are indeed a bottleneck for sound, but most audiophiles are not aware of it and as a result, so far, neither are the manufacturers. I'm sure they'll figure it out someday.

LED indicator lights have also been found to slightly pollute the sound as well.

Indeed, but often the traditional incandescent lights on older gear are measurably worse. When my old Quad 303 power amp was refurbished a few years ago the service engineer showed me  on the scope the improvement made by using a led compared to the old incandescent bulb.

OP
If I were building an amp the power switch would be a concern. If I’m not building one, but buying one, altering it would be of no value to me. I mean, why? Why fix something that is not broken?

Manufactures decide on what kind, type, and level of power sw they will use in what ever amp they make.

I have not heard too many arguments on $10K or more priced amps power swituches being crap and needing replacement immediately or for that matter, at all..

I’ve owned mono tube amps that ran $7500 a pr. Which used a $1 toggle switch. They sounded fabulous.

The amps, not the switches. The switches just sounded like ‘click’. Louder if you really put a little something behind it when you flipped them on or off.

I made one alteration to those amps. Opened them up to allow the leads connected to the biasing pot to be extended outside the amp to by pass the on board meter so a better easier to see volt meter could be used when biasing or checking bias.

Furthermore, the ON/OFF sw of and by itself, makes no argument for or aginst power cords or for that matter any other connective cabling. To think so, is ludicrous.

The sonics of an amplifier do not hinge on the value of its power switch. There is far more to the amp than that.

Go read up on Shindo amps. $20K and up lower powered tube amps and see what kind of power sw is used. I’m certain it will open your eyes.

As well, not every ON/OFF sw is seeing full current or remains in the ckt at all times. Some do. Some do not. Relays are used to dispense power about the amp and are a part of many amps ‘soft start’ opwerational system.

I tend to think about the audio-nervosa minutia this way… of all the things one might do to improve the sound of an amp, is completely reworking the power switch the obvious path to follow given the amps already quite possible outstanding sonic results?

If one is thinking of how to improve the sound of an amp, maybe it is time to find another amp, well, if it is an SS amp.

Messing around there has never even crossed my mind, until a knife sw on a former preamp I bought here was broken off during shipping. What did I do? Sent it back to the maker to have the exact same switch put in place of the broken one. Problem solved. Results? Excellent. No further worries.

I’d worry about more tangible and meaningful areas to improve the presentation… not swapping out switches. But that’s just me.

Enjoy.

I've never tried a higher quality on/off switch, but I just know it can't possibly make a difference in the sound. Just like fuses. Trust me, I read a book about how electricity works, and understood some of it 😉

The same argument can be made for internal wiring.  People spend thousands on expensive speaker cables only to find out that their speakers are internally wired with lamp cord. 

+1

And then there are people who spend thousands on speaker cables and power cords and DO either upgrade internal wiring or know that the internal wiring is up to snuff.

You can't really pick one instance of silliness and call it proof..

If you need the switch in place, consider something like the higher-quality, silver-contact, 2-way toggle switches. Online electrical supply houses often have them. Parts Express might have one or two, I don't know. Also try Goldpoint.

Thank you for the suggestion, Ivan. Parts Express has a couple of decent switches. I would appreciate a heavier duty switch that can accept thicker wire and has a solid contact made from good conductors.  Didn't find a suitable product by Goldpoint.

Thank you for your response blindjim! You have covered a lot of points here.

If I were building an amp the power switch would be a concern. If I’m not building one, but buying one, altering it would be of no value to me. I mean, why? Why fix something that is not broken?

I am trying to build my own tube amps, and the question about the on/off switch came as part of the parts selection process. I am also tweaking/upgrading my commercial tube monoblocks…

Manufactures decide on what kind, type, and level of power sw they will use in what ever amp they make. 

Yes, and every manufacturer has to do compromises with their design. Sometimes cool design takes priority over good electrical contact and this large LED glowing button with super tiny pins at the end is a winner (and a compromise).

I have not heard too many arguments on $10K or more priced amps power swituches being crap and needing replacement immediately or for that matter, at all..

I agree with you. I have not heard such arguments either. But I also have not heard too many arguments on $10K or more prices amps fuses being crap and needing a replacement immediately... But people replace the fuses and think it's for the better. So my argument is that if a fuse makes a difference, why would not the switch make a difference too? And I am only referring to the on/off switches that are part of the voltage circuit... not those that just command relays... but I will get to that in a little bit.

 I’ve owned mono tube amps that ran $7500 a pr. Which used a $1 toggle switch. They sounded fabulous.

The amps, not the switches. The switches just sounded like ‘click’. Louder if you really put a little something behind it when you flipped them on or off.

Same comment about fuses as above. 

As well, not every ON/OFF sw is seeing full current or remains in the ckt at all times. Some do. Some do not. Relays are used to dispense power about the amp and are a part of many amps ‘soft start’ opwerational system.

You are absolutely right here! I do not think that on/off switches that command relays would make any difference. I should have clarified that.

If one is thinking of how to improve the sound of an amp, maybe it is time to find another amp, well, if it is an SS amp.

Possibly. I use tube amps, not solid state. I have expensive SET monoblocks that sound amazing and don't want to replace. They sounded really good from the factory. But replacing the decent caps they had inside with the top of the line V-Caps made a quite significant difference. Replacing the stock power cord and fuse with better quality made some improvement too. Changing some resistors in the signal path with higher quality and the internal signal path wiring also made an improvement. The thing that bothers me now is the cheap wire that goes from the IEC on the back to the cheap power on/off switch on the front and back to the rear of the amp. I would like to bypass all that, put a 2-way switch near the back of the unit, and use short and better wire. Maybe it would impact the sound, maybe not. As I said in my original post, I think that if a power cord, fuse, power outlet, IEC inlet makes a difference, it sounds logical to me that removing the excess and crappy internal wire and replacing the crappy switch would make a difference...
I like to do all these optimizations before I move on to the next class, which would cost at least 20K more. 

I’d worry about more tangible and meaningful areas to improve the presentation… not swapping out switches. But that’s just me.

Very good point.

tommylion207 posts11-01-2017 7:13amI've never tried a higher quality on/off switch, but I just know it can't possibly make a difference in the sound. Just like fuses. Trust me, I read a book about how electricity works, and understood some of it 😉

Tommy - point taken. If fuses don't make a difference, there is no need to discuss the power switch.  

There was a time I did not believe that cables make a difference. And I am not even talking about power cords here... I am talking about speaker cables, interconnects, etc. And guess what? I was right! They did not make a difference in my system at the time. That time is way in the past now. As the resolution of my system was improving, I started to hear what difference various components of my system make. Or maybe my brain is playing tricks with me... but hey, if replacing a fuse does not make any difference in the sound, but tricks my brain to think the sound is better, I would still spend the extra $50. Not to make my system better but to trick my brain :).

I don't want this thread to turn into a fight if power cords or fuses make a difference. There are plenty of threads like that here we can probably read for days... 

What I would like to hear is suggestions for a good quality power switch or if people believe that all those components in the power grid make a difference but the power switch does not, I would like to know why. The fact that I could not find a high-end switch in the typical boutique parts stores for audiophiles suggests that my logic may not be that solid after all.  

It has actually been discussed on quite a few threads here and the best idea put forward and used by at least one amp manufacturer was to use a circuit breaker in place of the on/off switch and the fuse.

Unless it is a tube component, I like to treat things like a love light...

Turn it on


and leave it on

My previous post was totally tongue-in-cheek. Having some fun with the kind of responses that those of us who do hear differences with these kind of things often get.

toddverrone684 posts11-01-2017 1:56pmIt has actually been discussed on quite a few threads here and the best idea put forward and used by at least one amp manufacturer was to use a circuit breaker in place of the on/off switch and the fuse.

Interesting... Maybe I did not use the right keywords in my search as I could not find any relevant discussions. I will try again. Thanks, Todd.

tommylion208 posts11-01-2017 6:10pmMy previous post was totally tongue-in-cheek. Having some fun with the kind of responses that those of us who do hear differences with these kind of things often get.

You got me! :) 

Nenon > my argument is that if a fuse makes a difference, why would not the switch make a difference too? And I am only referring to the on/off switches that are part of the voltage circuit...
I would like to know why.

Blindjim > short answer? The amps power supply.

The more entertaining and far longer answer…

It sure seems like you are doing your due diligence pondering this portion of the power ckt. I suppose you could micro manage it further if no upscale sw or IEC port, is found by having contacts plated with whatever, and or cryo treated.

It seems to me amps have addressed the power issues which could possibly stem from the use of a non descript run of the mill wiring and pwr sw in their power supply via filtering caps among whatever else in that section supporting signal processing.

As you said you altered these caps and realized a noticeable gain in performance, or at least liked what came from it.

Given that line of reasoning, do you feel backtracking to the IEC input and facilitating changes there is really necessary? It would seem an inconsequential effort as the power supply components were previously addressed.

I’ll use the refining crude oil into fuel analogy. Sounds like someone wants to use a better crude oil pipeline, or funnel in order to acquire a better octane..

In nearly any powered audio component, to improve upon its present performance (and this often occurs only in the middle area or below of audioland, not it upper tier or ultra high end ranges) the ‘POWER SUPPLY’ is where most every modder will begin snipping and soldering.

Why? Its where power line issues are getting the most attention. Some components even incorporate on board power line conditioning sections for their appliances.

Quick and easy remedy here? Think Bi Bee. Bus bars. Etc.

If access to these possible areas for alteration are easy to access, meaning the wires associated with the incoming power, power sw, and wires to the pwr sup, maybe merely adding a layer of shielding to the conductors would be a place to start experimenting. Albeit, I’d not suspect major gains there, I’d suspect a prevention of possible collateral interference from radiated energy ought be ameliorated at least with the addition of shielding.

To change these wires out entirely and as well shield them may yield a tad more change, but in both cases, wires and shielding wires, remember, the power sup is dealing with the incoming power already pretty well. Possibly as well as it is able in its current state, which btw, is its job.

Then too there is the aspect of metallurgy. Maybe the desired wires and or solder used don’t’ add up to a discernible end or even positive outcome.

Something tells me many amplifier makers have at some point gone down this rabbit hole in the past. Probably tons of them. What you see in their builds must be considered their best solution. And yeah, this means those amps that are put together by hand too.

I suppose one could do what all other makers do, and buy a uber expensive competitors product and do some reverse engineering or merely take a look see at how they’re keeping their portion of market share.

I’d try hard to have a talk with the maker of the amps design I’m following before fishing in that pond too long, or maybe, at all.

As for fuses making an audible positive gain in performance? Sure. Sure they do. Until I experience that one myself, my response will remain skeptical. As will which direction the thing gets inserted into its clips or fuse holder.

Buying some of these mystical magical one and done little ckt savers, will likely occur on a bet, or I’d not do it/them at all. At $50 or more ea. Goes a longer way towards media. Or a really, nice hat band, pocket watch fob, K cup assortment, etc..

Gotta go. Game 7!!!

Hope you find your pot of gold. Best regards…

nenon,

Reading from your subsequent posts, I think maybe I've been going about this all wrong. Since you're building your own amp And you need the switch installed at the rear panel before the fuse and power supply, then that may change our game entirely. It will be easy IF you have room enough in your chassis to swing it, but here we can likely dispense with considering the usual small, or "miniaturized", switches and focus on the "large" switches instead. These (heavy duty) switches have a form factor that allows them to be a drop-in replacement into a standard residential light switch...I know this is a rather large size to think about putting in an amp build, but I think this likely the way to go and I'll tell you why.

With the form factor this large, all your wire gauge and soldering concerns are eliminated. Just one I happened to look at from Hubble (HBL 1201IL) has a solid copper contact arm with both large contact, surface patches being silver (not some silver alloy) (necessary in these larger, heavy-duty switches to prevent welding). The contact arm and internal wiring are generously beefy and you just connect your large gauge wires to the screw terminals, same as with any other light switch - no soldering at all, and the contacts can be cleaned out as often as you ever need. This switch comes in single-pole, 15A, 20A and 30A. Online prices for these types of switches appear to be roughly anywhere between $20 to $50 each, depending.

But, like I say, maybe the only real concern with this type switch is whether or not your chassis can be made to accommodate the larger size and how difficult it will be to drill for the switch cutout. Exact dimensions are always available online with these large switches, along with all the specs.

But, in short: heavy duty, correct amperage rating for your app, best materials, easy to connect/disconnect. 

Even if it's a challenge to install something like this in your rear panel from a practical standpoint, I think that I would much rather try this than a circuit breaker since (you guessed it) they too degrade the sound (as virtually Any switch or connector can be expected to do, really)...even the ones in our circuit breaker box, but there's not all that much that can be done about that, of course.

Hope this helps.

Congrats to Astros fans. Finally a world series win!!

I did neglect to address your other Q’s in your OP, but I’d say that your original instincts are correct about that if all the other AC ancillaries (power cords, fuses, power supplies, IEC inlets, duplexes, etc) are fair game for ’getting it right’, then why not on/off switches? I concur. Might throw in fuse holders too, really. In fact I’d say that ALL switches, connectors, fuses, breakers, et al, are The Spawn of Satan in the audio world. The best sounding connector or switch, ideally, is none at all...hardwired bypass will always sound better. But, what can we say, there’s no practical way to live with a "hardwired bypass" condition on everything - totally impractical, impracticable, and definitely downright dangerous! So they are evil - but, a necessary evil, so we accept them and what they can do for us in the real world.

As for an amp power switch, most of the time, from a purely operational standpoint anyway, we might consider for a moment that a power switch for the usual hifi amp may not even be necessary. We could, if the amp is not in a rack or cabinet, just plug and unplug the power cord, presumably, for amps that are not to be left on anyway. 

But, in practice, this can be a little dicey sometimes. Unplugging or plugging in too slowly or awkwardly can exaggerate the arcing at the contact points and the arcing may be enough in some circumstances to blow that expensive designer fuse, or perhaps do some kind of damage to the amp, even whether it has some measure of protection or not. Even if no damage to the gear ever occurs, the carbon buildup inside the female AC receptacle will be frequently occurring and impossibly difficult to clean.

And suppose that very rare instance occurs to you one day and your amp suddenly is making a very LOUD and nasty noise and in a second you realize that the power has to be cut immediately or the worst may happen. If the power cord were momentarily inaccessible (as in the rack or cabinet scenario), then the front-panel switch could be a gear saver. An available switch would be the fastest and most reliable way to avoid imminent meltdown. Rare maybe, but in the life of many an audiophile, that day has already come...or is probably going to.

So, for those practical concerns alone, I’d argue that the switch is necessary...and that as long as that’s true, then it might as well be audibly the best kind for the job that is still affordable overall.

When you make Power amplifiers with extremely large power supplies the on/off function becomes an important issue, not only for being able to start the Amplifier but also for making the switching function last for a very long time.  

The on/off function in our Olympia power Amplifiers are made with a 40A Triac in series with 4 Inrush Current limiters in series parallel - once the initial inrush current is over  (which is VERY large when using a 4KVA transformer / 1 Farad  power supply)  2 each 20A relays with 2 contacts on each (theoretically capable of switching 80 Ampere) bypass the Triac/inrush limiter circuit.   To turn off the amplifier the low level signal to the relays coils are switched off.

This have proven a very reliable way to handle the on/off function. 

http://pbnaudio.com/audio-components/audio-amplifiers/olympia-ebsa-3

Good Listening

Peter 

"Note. The power switch is a snap switch and should always be manually closed and opened in quick follow through movement. Especially on power amps. This will help in preventing of arcing when the switch is being opened. Arcing can/will cause pitting of the contact surfaces. Sufficient pitting will result in lower conductivity through the closed contacts. Enough pitting will cause a VD, voltage drop, to be created across the contacts of the switch. With VD, heat, followed by carbon, followed by more VD, more heat, arcing, and eventually the switch will fail."

Absofreakin'loutely. Great point about reliability.

"When you make Power amplifiers with extremely large power supplies the on/off function becomes an important issue, not only for being able to start the Amplifier but also for making the switching function last for a very long time."   

Agreed again, another great point: the more power, the more the concern about the power switch.

The power switch under normal circumstances is not necessarily the biggest concern in the power path, true, but if you're building and looking to upgrade the whole chain, then perhaps it should not be forgotten.

Regards to all, John

Power conditioning?  Yeah it works (and has more effect with some components that others).

Power cords? Not so much

Power switches - not much effect at all so long as they make a good solid contact.

And I'd add to that, that they must be up to the job of switching whatever amperage goes through them.  I have one Class A power amp that has welded two switches closed so I just turn it on and off with a heavy duty power bar - I didn't want to start modifying the front plate to accommodate non-stock switches, nor to change circuitry to reduce turn on draw.