SS Sound vs. Tube Sound (for the umpteenth time)

[mep]

Firstly and technically the krell doesnt double down for every halving of load , close but not technically true , now back to toobs ..

Really? Please post links to reviews with measurements that prove your point. And are you splitting some proverbial hairs here? Check out Stereophile's measurements and I rest my case.

Toobs are Technically superior to SS in two most critical areas ,

1. Toobs are Highly linear without negative feedback, specially some small-signal types, hence they are excellent for pre's and amplifier VAS stages ..this is a huge advantage for tubes....( where are the hybrids )

We are now seeing SS amps and preamps that don't use negative feedback and have measurements that are beyond reproach. Ayre is one example I can think of right off the top of my head.

2 Clipping is smooth, which is widely considered more musical than transistors, for this reason A 100 watt toob amp can sound more powerfull than a 200 watt ss, because you can actually push a toob amplifer into a 3db overload situation before the sound becomes offensive , where at 50 % of rated output on an SS amp would have most heading for the volume control knob , to reduce the offensive grunge ..

While it is true that tube amps clip more gracefully than SS because they tend to compress the top of the waveform instead of cutting it off, they still can't sound twice as powerful no matter how many old wive's tails you believe in. A 100 watt tube amp can only put out 100 watts. It can't put out 200 watts no matter how much you want to believe it can. By contrast, a true 200 watt SS amp is always a 200 watt amp and a 100 watt tube amp is always a 100 watt amp. The moral to the story here is don't clip your amp.

 

[microstrip]

With regards to the Krell KSA-250, I can only surmise it's due to the incredible power supply. The bass sounds incredible because the power supply is incredible. And I use the word "incredible' because any amp that can keep doubling down the power each time the impedance is halved all the way down to .5 ohms and 4kW has an incredible power supply.

Sorry but the argument is very poor. Although this could be true using very inefficient low impedance speakers, your speakers will never drain this type of power at normal listening levels. Incredible is not an electrical property.

BTW, at some moment in the 80's it was fancy to DIY people (such as me at that time) to beef power supplies with very large capacitors and very heavy power transformers. But they do not became Krell's.

 

[mep]

OK Micro, what is your explanation? The heart and soul of any preamp or power amp is the power supply.

 

[microstrip]

OK Micro, what is your explanation? The heart and soul of any preamp or power amp is the power supply.

I wish I knew. The power supply must be matched with the amplifying section - as some people like to say the power supply is in series with the signal.
Many designers presented theories about the need of this matching - just remembering the Naim and Electrocompaniet designers. One thing was sure for me - just beefing the power supply did not improve the performance most of the time.

 

[opus111]

While I agree with your statement that noise floor characteristics should be an overall system objective, I couldn’t disagree more with your statement that noise floor characteristics are neither tube or SS dependent. Tubes inherently have a higher noise floor than SS and that is just a fact that some either don’t know or choose to ignore.

'Noise floor' means different things to different people. I suspect here the meaning isn't the background hiss level when no music is playing, rather the silence between the notes. Tube amps undeniably come with higher levels of background hiss in general.

There is a reason that most modern tube preamps and power amps use JFETs on the input side of the circuit in order to increase gain and lower noise.

Do you have a reference for this claim? In my understanding JFETs are used because they sound good, potentially its also a fashion thing. One thing's for sure, JFETs do not have increased gain (where 'gain' means transconductance) over bipolars, they do have a noise advantage in certain circuits where the impedance is high, though it depends on the particular JFET in question. If a high input impedance is a requirement to an amp then a well-chosen JFET will be quieter than a bipolar.

One reason that JFETs are thought to sound good is they have superior rejection of interfering RF signals over bipolars. In that respect they're more like tubes - there's no propensity to AM demodulation. For myself I suspect this is the primary reason that SS amps don't in general have the tonal purity of tubes - ingress of RF makes their sound greyer due to intermodulation distortion.

 

[A.wayne]

Really? Please post links to reviews with measurements that prove your point. And are you splitting some proverbial hairs here? Check out Stereophile's measurements and I rest my case.



We are now seeing SS amps and preamps that don't use negative feedback and have measurements that are beyond reproach. Ayre is one example I can think of right off the top of my head.




While it is true that tube amps clip more gracefully than SS because they tend to compress the top of the waveform instead of cutting it off, they still can't sound twice as powerful no matter how many old wive's tails you believe in. A 100 watt tube amp can only put out 100 watts. It can't put out 200 watts no matter how much you want to believe it can. By contrast, a true 200 watt SS amp is always a 200 watt amp and a 100 watt tube amp is always a 100 watt amp. The moral to the story here is don't clip your amp.

You should read my post again Slowly .. Geeezhhhh lol ...

Mep,

regardless of what you think you know or will know next week , doesn't change the fact that tubes still have the advantages listed, you should read again ....

Regarding your Krell go back and look at those Stereophile test , try and understand the difference between reality and advertisement , look at the 8 ohm power output make a note of the thd measured at that power output , then Tell me what the power output is at 4/2/1 at the same THD .....

WAS IT DOUBLE THE POWER .....

 

[MylesBAstor]

'Noise floor' means different things to different people. I suspect here the meaning isn't the background hiss level when no music is playing, rather the silence between the notes. Tube amps undeniably come with higher levels of background hiss in general.



Do you have a reference for this claim? In my understanding JFETs are used because they sound good, potentially its also a fashion thing. One thing's for sure, JFETs do not have increased gain (where 'gain' means transconductance) over bipolars, they do have a noise advantage in certain circuits where the impedance is high, though it depends on the particular JFET in question. If a high input impedance is a requirement to an amp then a well-chosen JFET will be quieter than a bipolar.

One reason that JFETs are thought to sound good is they have superior rejection of interfering RF signals over bipolars. In that respect they're more like tubes - there's no propensity to AM demodulation. For myself I suspect this is the primary reason that SS amps don't in general have the tonal purity of tubes - ingress of RF makes their sound greyer due to intermodulation distortion.

http://members.quicknet.nl/ra.vdsteen/pdfs/Audio_Electronics_JFETs.pdf

This paper by John Curl has been dissed by some member here but it contains the thoughts of one of the most well read and respected audio designer. Besides, he's been using at the time of this piece, JFETs in his designs for 30 years. One does have to search through for his experiences on what to do and not to do with JFETs.

http://www.q-audio.com/johncurl.pdf

 

[A.wayne]

Mep,

Its like this , make a 350 watt per channel amp , derate it to 200 watt/ch @8 ohm and then use the highest Thd measured at 2ohm and guess what it doubles down to 2 ohm ....

Industry secret .....

 

[A.wayne]

http://members.quicknet.nl/ra.vdsteen/pdfs/Audio_Electronics_JFETs.pdf

This paper by John Curl has been dissed by some member here but it contains the thoughts of one of the most well read and respected audio designer. Besides, he's been using at the time of this piece, JFETs in his designs for 30 years. One does have to search through for his experiences on what to do and not to do with JFETs.

http://www.q-audio.com/johncurl.pdf

Yep and agree on the Jfets ..... !!!!!

 

[Bill Hart]

MEP, when you say the 'bloom is off the rose,' do you mean that despite all the positives of SS that you mentioned, you are still missing something in the sound compared to tubes? I was reluctant to comment on your solid state experience because mine was literally decades ago (having stuck by tube stuff, by and large, since mid-70's), but since you are basing some of your views on older solid state amps, the Krell and Phase Linear, perhaps a newer solid state amp has some of what you may be missing. My experience, which is admittedly anecodotal, and not defining of either design 'camp' is:
1. I get very low noise or tube rush using tube equipment all the way through the chain, from phono, to line stage, to main amplifiers, over even more efficient speakers (104 db);
2. I get good bass from an 18 watt SET amp;
3. When I had the Lamm line stage, i was always amazed that it was a solid state audio path (albeit with a tube power supply) and it had a wonderful, grainless and very coherent midrange. Maybe that was the power supply, I don't know.
4. When I had the Steelhead, running it without an additional line stage, straight into the amps, it did not have the nuance and 'real life' quality that I expected, even with the best NOS tubes and a substantial separate power supply. It had FETs, as did the Lamm line stage, but somehow, in the execution, one (the Lamm) had warmth and richness and the other (the Manley) had the frequency extremes but sounded a little one dimensional and almost grainy.
What's the punchline? I don't think there's an easy answer. Part of it is execution of the particular design, some of it may be that dreaded 'synergy' among the components, getting the noise floor and AC power sorted, etc. My sense is that back when I started in earnest in this hobby in the early 70's, the differences in character of tube and solid state designs were more stark- tubes were rich but tubby and solid state had the grip and detail but sounded too analytical and lifeless. To borrow from the 'methinks' lexicon, maybe things have improved in the last couple decades.....
But, I get the advantage of not fussing with tubes.
Someday, I'll experiment with something like the Dart, if it is still at the top of the heap when I'm ready.

 

[opus111]

http://members.quicknet.nl/ra.vdsteen/pdfs/Audio_Electronics_JFETs.pdf

I've long been a fan of Erno, the first amp I ever DIY'd was one of his designs from Wireless World magazine. Didn't have any JFETs in it though. Erno's views on MOSFETs influenced me in my younger days. Were you citing this paper to support mep's claim of higher gain? If so where does he compare with bipolars?

As for the Curl paper, I read it a few years back. It has some merit, mixed in with plenty of political nonsense.

 

[MylesBAstor]

I've long been a fan of Erno, the first amp I ever DIY'd was one of his designs from Wireless World magazine. Didn't have any JFETs in it though. Erno's views on MOSFETs influenced me in my younger days. Were you citing this paper to support mep's claim of higher gain? If so where does he compare with bipolars?

As for the Curl paper, I read it a few years back. It has some merit, mixed in with plenty of political nonsense.

Just posted it as an overview of JFET technology

 

[Gregadd]

I think more and more the differences between ss and tubes are dependent on cost and the skill/preference of the designer. Indeed some of the best speakers I have heard of late, with some exceptions, were driven by solid state. Alas the best solid state I find to be prohibitively expensive.

 

[opus111]

Its not so much what components you use but the way that you use them so yeah I agree. Lynn Olson (whose listening skills and impartiality I hold in high regard) says he's heard a few (I think it was three at last count) SS amp designs that sounded like tube ones.

 

[MylesBAstor]

Its not so much what components you use but the way that you use them so yeah I agree. Lynn Olson (whose listening skills and impartiality I hold in high regard) says he's heard a few (I think it was three at last count) SS amp designs that sounded like tube ones.

Solid-state reproduces certain musical elements and tubes reproduce different musical elements I think one does a disservice trying to say a ss amplifier sounds like a tube amplifier or vice versa (I've yet to hear that unless it's a poorly designed tube compared to ss); what's important is do they sound like music?

It seems to me that just as tubes and high end audio went through a period of hyperdetail, solid-state went through a period where designers were adding coloration to make their ss designs sound darker and like tubes. Thankfully, sanity has returned and both camps are back to making music!

 

[Gregadd]

Solid-state reproduces certain musical elements and tubes reproduce different musical elements I think one does a disservice trying to say a ss amplifier sounds like a tube amplifier or vice versa (I've yet to hear that unless it's a poorly designed tube compared to ss); what's important is do they sound like music?

It seems to me that just as tubes and high end audio went through a period of hyperdetail, solid-state went through a period where designers were adding coloration to make their ss designs sound darker and like tubes. Thankfully, sanity has returned and both camps are back to making music!

Agreed. I think digital forced ss to change. As digital improved ss could return to its true personality.

 

[opus111]

Solid-state reproduces certain musical elements and tubes reproduce different musical elements

Can't agree there with the word 'muscial', but otherwise yeah. Amps don't appreciate music, they're just machines so they can't pick and choose 'musical elements' to reproduce or not.

I think one does a disservice trying to say a ss amplifier sounds like a tube amplifier or vice versa (I've yet to hear that unless it's a poorly designed tube compared to ss); what's important is do they sound like music?

I was summarizing, editorializing to fit the format - I agree largely with this. To expand a little on what Lynn was saying, he notices most SS amps have a metallic colouration which is absent amongst tubes. I think the same metallic colouration when reduced in level doesn't sound so metallic, just adds a general greyness to the tonality. My criteria for 'goodness' of electronics isn't 'does it sound like music?' but 'is it interesting to listen to?', does it hold my attention, draw me in? That's the same metric for goodness as I use for a novel or a movie.

 

[MylesBAstor]

Can't agree there with the word 'muscial', but otherwise yeah. Amps don't appreciate music, they're just machines so they can't pick and choose 'musical elements' to reproduce or not.

Well if you go the reductionist route, we can talk about each components strengths and weaknesses, eg speed, spatial resolution, dynamics, microdynamics, timbre, frequency extension, control, etc. Each design does each of these differently.

I was summarizing, editorializing to fit the format - I agree largely with this. To expand a little on what Lynn was saying, he notices most SS amps have a metallic colouration which is absent amongst tubes. I think the same metallic colouration when reduced in level doesn't sound so metallic, just adds a general greyness to the tonality. My criteria for 'goodness' of electronics isn't 'does it sound like music?' but 'is it interesting to listen to?', does it hold my attention, draw me in? That's the same metric for goodness as I use for a novel or a movie.

I think that that area of sounding metallic/mechanical has been vastly reduced in most of the best ss amplifiers out there. For how does it hold my attention: that varies among people but we can go back to the primal brain which will look and even go to great length to avert pain rather than seek pleasure. That's engrained and automated in our brain and so it is for me that upper midrange/harshness in equipment.

 

[Raffles]

Without blind testing etc. I don't think you can label SS as 'grey' or 'metallic' or anything else. Likewise valves being 'warm', 'smooth' or 'musical'. What I do know is those descriptions are exactly how I would expect those devices to sound - if I believed that a thing naturally sounds how it looks.

From personal experience, I know that some people like to watch their TVs with the colour turned right up. When I read opinions that state, in all certainty, that solid state, or digital audio, sounds metallic or harsh or 'grey', how do I know that the person saying it is not the audio equivalent of the 'full saturation' viewer? It is very easy to be made to feel inadequate reading these forums if you don't actually hear this factually-certain greyness in solid state amps or digital audio!

 

[flez007]

3 topics I retain from commenting:

1.- Politics
2.- Religion
3.- Tube vs. SS debates