[werd]

Wow, 7 pages allready!

I'm still in the middle on this one. I love both for different reasons and I accept both for what they are. I really like to run SS for about a week, then switch to Toob for another week, oscillating back and forth. To be honest, it really seems that the weather affects which amp I listen to. Both of my amps (that I switch back and forth) sound so very close, but the differences are real. The SS has better imaging to a slight degree, while the toob has a slicker midrange, almost buttery. I may have to also say that I might like some classical music on the Toob, but not always, depends on the band. And I usually prefer rock on the SS, but that also depends on who it is.

Ya, I know, I'm not much help.

Wayner 

Hey Wayner

Screw this SS vs Tube crap..... lets go launch the boat, throw the rod in and get pist.....

[JakeJ]

Screw this SS vs Tube crap..... lets go launch the boat, throw the rod in and get pist.....

Ahhh, now here's a voice of reason!  I must say this thread has been very entertaining.  From Page 2 on things have been a hoot.  I can appreciate a person being passionate about this or that but in this case there are some who might consider just turning off all the electronica and go out to play in the sun. 

On the outside looking in,
Jake

[DSK]

As Iam not radical, in last case I can accept a SS amp, since it is Class A output, because without alot of heat there is no sound quality.

An engineer I respect greatly has said that Class A is a way of getting acceptable performance out of almost any amp design. It covers up a lot of sins.

On the other hand, a well-designed Class AB amp will outperform a Class A amp, be vastly more efficient, and be more reliable.

I don't know about that.  It seems to me if there are alot of "sins" in the design it would be unreliable by default.  Nelson Pass is very well respected among most, I would guess, and I own his Aleph 0s which has performed flawlessly for the 5 years I've owned it (knock on wood).  I would assume it's a good design with few, if any, sins.

As for performance of A vs. A/B, the Class A SS amps have been the only SS amps that have stayed in my system for any length of time.  On paper maybe A/B outperforms A but not to my ears, where I'd say it counts.

Can't argue with you about efficiency.  But what audiophile cares about efficiency when you've got great sound?

As in most things, I think it comes down to the implementation. I used a Plinius SA100 mk3 class A amp for several years. It was very nice in most respects but was outperformed by the Aspen amps (class A/B) so I jumped ship. Despite the huge heat sinks, the Plinius sure used to get hot. You couldn't rest your hand on the the top for more than about 3 seconds.

I've also heard the claim that class A amps are easier to design then class A/B amps for a given quality level.

[turkey]

Hey Turkey, that test you mentioned is very interesting!  I wonder though if you were actually comparing the mike's ability to record that sound to the natural sound.

I'm sure that was part of it, although if I remember he had some very good condensor mics.

A more rigorous test would require making comparisons with some different mics to see how that changed things. You could change other aspects of the recording process too.

I'm not sure that mics are really the problem in the recording/reproduction process though. The stereo recording method itself has issues, but I think you can get mics that are very accurate.

There are also relatively few problems all the way through the rest of the chain until you get to the speakers and listening room. (Assuming you don't use vinyl records for storage, since they have major problems of their own.)

It is the speakers and listening room where the big problems are. Using headphones can avoid some of this, but standard stereo recordings aren't really ideal for headphone use. Still, headphones can allow for good FR and reproduction of transients.

[turkey]

I don't know about that.  It seems to me if there are alot of "sins" in the design it would be unreliable by default.  Nelson Pass is very well respected among most, I would guess, and I own his Aleph 0s which has performed flawlessly for the 5 years I've owned it (knock on wood).  I would assume it's a good design with few, if any, sins.

Poor performance is not always the same as poor reliability.

NP is a great guy, and a very talented engineer. He has come up with some very clever designs too.

In the case of the Aleph 0, it would be interesting to lessen the bias and see what it sounds like. All kinds of sins might be revealed. Not unreliability, since Pass tends to overbuild, but sonic aberrations.

As for performance of A vs. A/B, the Class A SS amps have been the only SS amps that have stayed in my system for any length of time.  On paper maybe A/B outperforms A but not to my ears, where I'd say it counts.

So all your Class A amps maintain Class A operation throughout their operating area?

Can't argue with you about efficiency.  But what audiophile cares about efficiency when you've got great sound?

When I can get equivalent or better sound along with greater efficiency, I choose efficiency. An amp that runs cooler also lasts longer, and I wish to keep my equipment for a long time.

[Ericus Rex]

Turkey, you are the Yoda of the HTML quote system!  I can't seem to figure out how to do it properly!  (see above post for evidence)

If all other things were equal I'd choose efficiency too.  I just haven't yet heard equal sound/performance when comparing A and A/B.

Yes, the Class A amps I've loved never switched to A/B.  But they have been lower wattage Class A, don't know if that makes any difference.  My Aleph 0s is 40 watts/channel and it replaced an original Bedini 25/25 which, SURPRISE!, was 25 watts/channel.  I've heard lower wattage ss amps have sweeter midrange, maybe that's why I like these two.

Can you lower bias on A/B amps without a change in performance/sound?  It seems to me, though I'm no expert, that a bias setting is an integral part of the functionality of the amp and changing that would be like removing the spark plug wire on a 12 cylinder Lamborghini and being surprised by a change in performance.  I'm guessing amp design (tube and ss) is a very complicated process and trade-offs are inevitable.  If it performs well when properly tuned (i.e. running at proper bias) what would lowering the bias prove?

[jon_010101]

The philosophy of most class B engineers is that, if you aren't going to run class A, it is better to skip AB and find a clever solution to the crossover distortion, instead.  The reason is that, at higher powers, the transition to AB leads to stronger crossover distortion than would occur at lower power transitions.  Of course - there is always the challenge that linearity is compromised with most devices running at low current - hence the preference towards variable bias schemes in solid state amps (Denon, Carver, Cambridge 840A), and clever output transformer arrangements in tube amps (McIntosh, Circlotron).

Personally, I only listen at levels <85dB, and can get by with a really clean 10W amp.  Class A linearity is, under the vast majority of circumstances, going to be greater than class B linearity at small signal, and since downward dynamic range is more important than upward dynamic range in normal listening, I'd prefer a class A tube amp.  There are many other advantages, too, in the design - simplified power supply, for example, despite the higher current demands.  Class B may be more fun/challenging to design, but a good class B engineering nerd should be able to surpass the small signal performance of their best class B amp with a class A design.

I should note, however, that my preference for class A isn't halting my design of a lean-bias class AB1 sweep tube amp - sometimes the exercise is more valuable than the product

[turkey]

Turkey, you are the Yoda of the HTML quote system!  I can't seem to figure out how to do it properly!  (see above post for evidence)

Actually, I don't know a lot of the tags that are available. You can get really fancy with this.

The idea is that you turn some feature on, and then have to turn it off when you're done. (You can also do things with the buttons on the editor screen above all the smileys, but I usually do it by hand because I'm used to it.)

So at the beginning of text you want to quote you would put a ]quote[   I have reversed the brackets on this so you can see where they go. If I put them the right way, the system would happily start a quote for me. So to do it for real you would have left bracket, quote, and then right bracket.

Then at the end of the text you want to quote, you turn it off with ]/quote[

You can do the same thing with an i tag for italic and a b tag for bold. I don't use any of the others, but I'm sure there's a lot of stuff you can do.

Just quote a paragraph, turning quoting on and then off at the end. Then type your reply to the paragraph. Then quote the next thing you want to respond to and so on.

It gets tricky when a thread has been going on for a while and there are multiple people being quoted. I tend to not touch the very first line that starts with "quote author" Then I'll remove any other quote lines and delete text until I get to what I want to reply to. By doing this I am simplifying things and only reply to and quoting one person's writing at a time.

Give it a try and then hit the preview button to see what it looks like. You'll get the hang of it.

If you're really interested, there are some docs at: http://www.audiocircle.com/index.php?action=help;page=post#bbc

I just played with the buttons and it looks pretty easy. Just make sure that you put your text in between the on and off tags as I showed above.

[turkey]

Can you lower bias on A/B amps without a change in performance/sound?  It seems to me, though I'm no expert, that a bias setting is an integral part of the functionality of the amp and changing that would be like removing the spark plug wire on a 12 cylinder Lamborghini and being surprised by a change in performance.  I'm guessing amp design (tube and ss) is a very complicated process and trade-offs are inevitable.  If it performs well when properly tuned (i.e. running at proper bias) what would lowering the bias prove?

I think this really depends upon the quality of the original design. If it was done well as a Class AB amp, raising the bias may or may not make it sound better. It shouldn't ever make it sound worse though (although if you crank it way up into the Class A range the amount of heat the amp produces tends to increase, and that could reduce the amount of power available for playing music rather than heating the room).

Some Class A amps are evidently mediocre designs that are given an easy fix by biasing them into Class A.

That's why I think it would be instructive to bias an amp back down into AB and see what it sounds like.

I once listened to a Perreaux amp while the bias was tweaked up and down, and it sounded pretty much the same as it was biased up and then back down to normal. (You need some minimum amount of bias to make it a Class AB amp and the engineer chooses the best point for that.)

There are some very nice kit amplifiers from Australia that you can build as either Class AB or A. It's the same basic circuit with some settings and mechanical things like heat sinks changed depending upon how high you want it to idle.

I haven't heard your Aleph amp, but I can say that I have found that NP's commercial designs seem to me to be rather expensive for the performance they give. They're not bad, but they're not better than less expensive amps.

I also don't like equipment that runs really hot. It's inefficient and tends to not last as long. That's just a personal preference.

The amp I have now actually never even gets very warm. It has very efficient heatsinks, and it doesn't throw out tons of heat. Most of the time you can't even tell it's been running, even after hours of being on. (It's not Class D either, it's a Class AB MOSFET amp.)

[stereocilia]

I had a Plinius SA100 mk ii with a switch to change the bias from 100% class A to class A/B.  I had a hard time telling the difference, and I couldn't do it reliably.  Of course, that may say more about my critical listening skills than the amp.  BTW I sold it because I couldn't get rid of a ground loop hum without a cheater plug.

[Wind Chaser]

Are there really folks that prefer solid state sonically?

The implication being anything with tubes must sound better than anything without tubes, because most folks prefer tubes.  Yeah, tubes are the ticket.  I got tubes in my turntable and tonearm.  Tubes in my cartridge and cables.  Getting tubes put into my telephone and doorbell too.  Can't stand listening to anything without tubes.  Nearly lost my mind over all this, but while at the hospital they shoved a few tubes up my arse and I'm all better now.

Seriously, most people have a mind broad enough to comprehend that tubes, like vinyl can sound like crap.  But if you're so naive to believe that the world is black and white, and white is better than black, you've been suckered into a vacuum void of reality...  Nevertheless there are some people who will prefer a solid state product that sounds better than something else with tubes that doesn't sound as good.

[Browntrout]

Windchaser I don't think the question was meant as you have chosen to take it. It is not reasonable to expect someone to qualify everything down to the nth degree, especially the title of a thread. As for saying you've got tubes in your tonearm I imagine most of us do, well one anyway.
  Right and wrong, up and down, left and right, good and bad, 0 degrees K (that's a joke by the way), the truth that's actually the only real absolute, the truth and that's is why it is what it is.
  A very happy and peacefull and safe Easter to you all, God Bless. 

[zybar]

I haven't heard your Aleph amp, but I can say that I have found that NP's commercial designs seem to me to be rather expensive for the performance they give. They're not bad, but they're not better than less expensive amps.

Those are fighting words partner!




While one can argue the value proposition of NP's commercial products (I am in the camp that believes they have a high level of performance for their cost), to make a blanket statement that they're not better than less expensive amps is something I can't just slide by.

If you are going make that claim, can provide examples of what you feel is superior and for less money?

If you (or a good friend) has some DIY skills, one can build one of Nelson's DIY projects at a fraction of the cost of the commercial products.  While I don't believe these will necessarily equal the commercial products, I know that they can sound darn good!! 

Lastly, I am huge fan of Class A amps.  Some of the best I have owned or listened to are pure Class A:  Atma-Sphere, Pass, and Kora to just name a few.

George

[jon_010101]

Some Class A amps are evidently mediocre designs that are given an easy fix by biasing them into Class A.

That's why I think it would be instructive to bias an amp back down into AB and see what it sounds like.

For an amplifier that is "properly designed", I can't say that I agree with this, since the design approach should be distinct between class AB vs. A vs. B designs.

For example, if a tube amplifier runs a class A output stage in a differential configuration, with a large shared cathode resistance or constant current source, then it will perform terribly at crossover, despite the distortion-reduction benefits under class A conditions.  Tube loading also differs for class A and B, and so will distortion characteristics.  The power supply requirements are also quite different: If a class A amp's power supply is designed for high constant current draw, it might perform poorly at low idle currents and ring on transients.  Similarly, unless incredibly over-designed, a class B amplifier's power supply is likely to overheat in class A.  

There are many other examples... But I'd argue that no truly good class A amplifier should be expected to perform well in class AB.

[zybar]

Are there really folks that prefer solid state sonically?

The implication being anything with tubes must sound better than anything without tubes, because most folks prefer tubes.  Yeah, tubes are the ticket.  I got tubes in my turntable and tonearm.  Tubes in my cartridge and cables.  Getting tubes put into my telephone and doorbell too.  Can't stand listening to anything without tubes.  Nearly lost my mind over all this, but while at the hospital they shoved a few tubes up my arse and I'm all better now.

Seriously, most people have a mind broad enough to comprehend that tubes, like vinyl can sound like crap.  But if you're so naive to believe that the world is black and white, and white is better than black, you've been suckered into a vacuum void of reality...  Nevertheless there are some people who will prefer a solid state product that sounds better than something else with tubes that doesn't sound as good.

Ummmm...I think you are taking the thread too literally and should chill.

This is the Tube-o-phile Circle and as such people will have this type of fun.

George

[Watson]

The implication being anything with tubes must sound better than anything without tubes, because most folks prefer tubes.
...
Seriously, most people have a mind broad enough to comprehend that tubes, like vinyl can sound like crap.  But if you're so naive to believe that the world is black and white, and white is better than black, you've been suckered into a vacuum void of reality...  Nevertheless there are some people who will prefer a solid state product that sounds better than something else with tubes that doesn't sound as good.

Not sure where you're getting that implication. Obviously there will be some bad tube amps that are bettered by good solid state amps. On balance though, most tube amps sound better than most solid state amps.

[pearsall001]

The implication being anything with tubes must sound better than anything without tubes, because most folks prefer tubes.
...
Seriously, most people have a mind broad enough to comprehend that tubes, like vinyl can sound like crap.  But if you're so naive to believe that the world is black and white, and white is better than black, you've been suckered into a vacuum void of reality...  Nevertheless there are some people who will prefer a solid state product that sounds better than something else with tubes that doesn't sound as good.

Not sure where you're getting that implication. Obviously there will be some bad tube amps that are bettered by good solid state amps. On balance though, most tube amps sound better than most solid state amps.

I think you have that arse backwards!!! But I must admit tubes sure do look nice in a dark room...that's about it though as far as I'm concerned.

[bunky]

My personal preference is Tubes for Power amplification and preamplification but Solid State has its merits as well 

[Bemopti123]

Man, what an argument about not much.  When one camp claim that the other is blind, it tells more about the camp's insecurity rather than the camp they are blaming. 

The biggest issue I have with SS is the packed print board issue, once something goes bad in there, good luck in trying to get it fixed, it is hell. 

Although there are some SS designs that are quite simple. 

SS and the packed circuit boards are signs of a technologically advanced and also a throw away society, that is my opinion.

I like both my tubes and my SS amps.  At low volumes though, tube has more presence and body.  SS, for me is a good thing for rock or other demanding tracks. 

[Ericus Rex]

Bunky, that was your 666th post!  Write another one quick!  BEFORE IT'S TOO LATE!!!!!