[Æ]

Then from the outside it would seem that ss amp is superior to a given tube amp. Same rough capability, no tubes to replace, no heat.

One thing that most audiophiles are unaware of, is that tube amps generally have more "real world" power.
They typically test, rate audio amps using a 1KHz tone into an 8 ohm load. If you took a supposedly 100 watt solid state amp and drove it with something broad band (pink noise) instead of the usual 1KHz, you end up with substantially less output. Maybe only 30 watts. Now if you conduct this same test with a tube amp, you end up having a higher percentage of power at the output.
Don't forget too, that tube amps generally clip gracefully, unlike solid state amps. When a solid state amp clips, it is easily audible and can even be harmful to the loudspeakers.

[BobRex]

Since the '70's FTC guidelines stipulate that the output rating is determined with a full bandwidth signal (20-20k i.e.; pink noise), can you site who specifies output power at 1kHz only?  Anyone who does that is technically guilty of false advertising according to the FTC.

Don't confuse John Atkinson's tests (which are done with a 1kHz signal) with how the product is specified. 

In fact, many solid state amps will measure better and be capable of higher power into higher frequencies than tube amps (those pesky tranformers).

[Æ]

Since the '70's FTC guidelines stipulate that the output rating is determined with a full bandwidth signal (20-20k i.e.; pink noise), can you site who specifies output power at 1kHz only?  Anyone who does that is technically guilty of false advertising according to the FTC.

Don't confuse John Atkinson's tests (which are done with a 1kHz signal) with how the product is specified. 

In fact, many solid state amps will measure better and be capable of higher power into higher frequencies than tube amps (those pesky tranformers).

I don't know all that much about the FTC rules, but 20-20KHz is just the minimum bandwidth of an audio amplifier, the usual specifications. Look at the printed specs for just about any piece of audio (stereo) equipment and you will see distortion measurements referenced at 1KHz. Sweeping the frequency all the way from 20-20KHz is one thing, delivering them all at once is another thing all together.
About 20 years ago I had some solid state Kenwood L-07M II monoblocks, which were rated YES, by the FTC at 150 watts into 8 ohms. You can confirm this, look up the rated specs for yourself. With the help of an audio engineer I test benched my amps, using real equipment like signal generators, true RMS voltmeters and wide bandwidth dual trace oscilloscope etc. My amps actually measured 170 watts into 8 ohms and 280 watts into 4 ohms (using a 1KHz sinewave). I also tested the amps at 20Hz and 20KHz too. These particular amps had substantially greater bandwith than just 20-20KHz. My Kenwood monoblocks would go from DC (zero Hertz) all the way to 600KHz and then some, but when driven with (bandwidth limited?) pink noise into an 8 ohms load, their measured power output was about 37 watts, before clipping!
I think you are missing my overall point. Test bench results using test tones are one thing, music is what we listen to. Testing an amplifier with music reveals something all together different than what the FTC mandates. Pink noise was chosen by my engineer friend because it covered the entire audio bandwidth and really revealed what an amp was capable of, or not capable of. If you are skeptical (non believer) run the tests for yourself. If you have a solid state amp(s), be prepared to be disappointed in how much power you really don't have when using pink noise as opposed to using individual test tones. Lastly, you'll find that tube amps tend to deliver a higher percentage of their rated power when playing music, more so than solid state amps.

[BobRex]

I understand you point, but your premise is flawed!  A couple of points:
1) The Kenwood amp was not rated by the FTC, it was rated by Kenwood.  Guess what -  like many Japanese manufacturers during the '70's they may have stretched the truth. 
2) I have run the tests myself. I spent close to 25 years selling audio products.  For a major part of that time, every amplifier that left the store was tested as to whether it met spec (including full bandwidth power output), tested via the Sound Tech suite, which included a pink noise generator as well as a distortion analyzer.  We also kept a scope connected so we could see the clipping. The majority of products we sold (Yamaha, Denon, Threshold, Hafler, McIntosh,...) met the power spec.  We would also test units customers brought in; many of the Pioneers, Kenwoods, Sansuis, Technics failed the test.  Either Kenwood "lied" or you had a bum unit?
3) While 20-20KHz may be the minimum bandwidth (no argument there), it is the FTC specified bandwith.
4) Tube amplifiers are bandwidth restricted.  This has been documented many times.  Due to the reactance of the OT, a tube amp will not deliver full output at the frequency extremes.  Ever hear / read the claims of flabby bass and soft highs?   

I'm not quite sure what to make of you last statement.  You claim to have tested a single (possibly flawed) SS amp, and from that you are extracting that tube amps deliver more of their rated power when playing music.  Sorry, technology and experience tells me that that's not the case.

Now before you think that I feel SS is sonically superior, take a look at my profile and figure out my preferences.

[woodsyi]

My krell sounds better when its warm! Thanks Rim, I was wondering why.

 

Hey, I heard a pair of Mosfet monos that were really good top to bottom.  Well, maybe not the first octave since it had active subwoofers.  Tenor 350s were the only amps at RMAF that really got the YG speakers to sing without harshness at the top and there were many YG speakers. 

To me this is the "warmth" I want.

[Æ]

There was nothing wrong with my amplifiers, they were bench tested and fully working. Yes, I'm aware that tube amplifiers are bandwidth limited, i.e. transformers. My "premise" is not flawed, because it didn't originate with me. It was a lesson taught to me by a very capable engineer with real credentials. He designed many amplifiers in his lifetime both tube and solid state. Some of his work ended up in the Space Shuttle program, The Indiana Jones ride at Disneyland and several of his ultra precision (tubed) calibration amplifiers are STILL in use at the NIST/Bureau of Standards. He was teaching me some of the differences between solid state and tubes. It certainly depends on the specific amplifier, but tubes do have the advantage. More Joules available because of the substantially higher power supply voltages. Your typical solid state amplifier CANNOT deliver full output at full bandwidth all the time. Amongst other places that I've worked in electronics, I spent some time at THRESHOLD final testing their amps before they went out the door, using an Audio Precision System. So I am experienced testing amplifiers both the old fashioned way and the more modern automated way.
There are certainly several kick a** solid state amps out there, but lets take an ordinary consumer 7.1 (multi channel) home theater receiver and put it to the test. Ha! FTC be damned. FTC rules are only there for truth in advertising, so manufacturers cannot inflate or make exaggerated claims. But whatever you believe is OK by me, not worth arguing with you especially since you already have your mind made up, being a high end salesman and all that. Most salesman really know how to hype it up, but beyond that they usually don't know the difference between a N and P channel device, don't know their Anode from a Cathode.

[woodsyi]

There was nothing wrong with my amplifiers, they were bench tested and fully working. Yes, I'm aware that tube amplifiers are bandwidth limited, i.e. transformers. My "premise" is not flawed, because it didn't originate with me. It was a lesson taught to me by a very capable engineer with real credentials. He designed many amplifiers in his lifetime both tube and solid state. Some of his work ended up in the Space Shuttle program, The Indiana Jones ride at Disneyland and several of his ultra precision (tubed) calibration amplifiers are STILL in use at the NIST/Bureau of Standards. He was teaching me some of the differences between solid state and tubes. It certainly depends on the specific amplifier, but tubes do have the advantage. More Joules available because of the substantially higher power supply voltages. Your typical solid state amplifier CANNOT deliver full output at full bandwidth all the time. Amongst other places that I've worked in electronics, I spent some time at THRESHOLD final testing their amps before they went out the door, using an Audio Precision System. So I am experienced testing amplifiers both the old fashioned way and the more modern automated way.
There are certainly several kick a** solid state amps out there, but lets take an ordinary consumer 7.1 (multi channel) home theater receiver and put it to the test. Ha! FTC be damned. FTC rules are only there for truth in advertising, so manufacturers cannot inflate or make exaggerated claims. But whatever you believe is OK by me, not worth arguing with you especially since you already have your mind made up. Being a big shot salesman and all that. Most salesman know how to really hype it up, but beyond that hey usually don't know the difference between a P and N channel device, don't know their Cathode from an Anode.

I believe you.  I like the 1950's vintage florescent lamp.  They sure made things to last back then.  New ballasts go out all the time. 

[audioengr]

Then from the outside it would seem that ss amp is superior to a given tube amp. Same rough capability, no tubes to replace, no heat.

You would think so, however thermal and power effects in transistors are difficult to eliminate, either FETs or Bipolar.  Tubes are very linear, particularly in the midrange frequencies, assuming a good design, and resistant to changes with temperature and even voltage.

The difficulty with lumping all tube designs as warm or smooth and SS designs as dark, cold or analytical is that you can actually have the reverse if the designs are right.  You can probably never get the super linear midrange of tubes, except with maybe power JFETs, like the D'Agostino amp. This is a game changer for SS IMO.

Having modded lots of tube electronics, and designed some of my own, I can tell you that its not usually the frequency response that usually makes for a smooth or warm sound.  Its the compression at HF.  This is not a characteristic of tubes, but can be if the power delivery is not optimized for HF.

This means that if the same care is taken with the power delivery system for a tubed component as for a SS component, they can sound virtually identical, save for the better midrange that is hard to match using SS.

When I hear a warm component, I usually attribute this to a poor choice of tube or the power system feeding the tube.  This is much more than just the power supply BTW, it is the circuit board, the cabling and the capacitor types, values and placement, as well as the speed of the regulation and type of regulation.

Steve N.

[Æ]

I believe you.  I like the 1950's vintage florescent lamp.  They sure made things to last back then.  New ballasts go out all the time.

Back then it was "American" made, now it's all made in China. I try and buy American whenever I can. Mostly though, I avoid stuff that's been made in China, not because I'm anti Chinese, but because most Chinese goods are crap. Unfortunately it's getting harder and harder to find anything that isn't made in China. Anyway, I always check for country of origin before making a purchase.

[Æ]

Having modded lots of tube electronics, and designed some of my own, I can tell you that its not usually the frequency response that usually makes for a smooth or warm sound. Its the compression at HF. This is not a characteristic of tubes, but can be if the power delivery is not optimized for HF.

Very interesting, I'd like to learn some more about this.

[audioengr]

Very interesting, I'd like to learn some more about this.

Okay, Ill throw one bone:

When you examine most power supplies for tubed electronics, you see single conductor wires for the plate voltage, and you see these conductors going to tube sockets or circuit boards where there are no power decoupling capacitors.


this would never fly in SS electronics because it would sound so bad, but with tubes, the currents are much smaller, so manydesigners think they can get away without it, or they just dont know they need it in the first place.  It ends up sounding tubey or warm,andthey bekjeve they have succeeded.  IMOthey have failed.

Steve N.

[BobRex]

There was nothing wrong with my amplifiers, they were bench tested and fully working. Yes, I'm aware that tube amplifiers are bandwidth limited, i.e. transformers. My "premise" is not flawed, because it didn't originate with me. It was a lesson taught to me by a very capable engineer with real credentials. He designed many amplifiers in his lifetime both tube and solid state. Some of his work ended up in the Space Shuttle program, The Indiana Jones ride at Disneyland and several of his ultra precision (tubed) calibration amplifiers are STILL in use at the NIST/Bureau of Standards. He was teaching me some of the differences between solid state and tubes. It certainly depends on the specific amplifier, but tubes do have the advantage. More Joules available because of the substantially higher power supply voltages. Your typical solid state amplifier CANNOT deliver full output at full bandwidth all the time. Amongst other places that I've worked in electronics, I spent some time at THRESHOLD final testing their amps before they went out the door, using an Audio Precision System. So I am experienced testing amplifiers both the old fashioned way and the more modern automated way.
There are certainly several kick a** solid state amps out there, but lets take an ordinary consumer 7.1 (multi channel) home theater receiver and put it to the test. Ha! FTC be damned. FTC rules are only there for truth in advertising, so manufacturers cannot inflate or make exaggerated claims. But whatever you believe is OK by me, not worth arguing with you especially since you already have your mind made up, being a high end salesman and all that. Most salesman really know how to hype it up, but beyond that they usually don't know the difference between a P and N channel device, don't know their Anode from an Cathode.

You talk about minds being made up - pot meet kettle!  I said that there were many Japanese products that never met their specs, Kenwood was a big offender, so it's logical that the L-07M may have been one of them.  So now you want to use a home theater receiver to back up your argument?  You're kidding, really!?!  I cited numerous examples of amplifiers that actually can meet spec (hell, you even agree that there are kick-ass examples) and yet you still hold on to your claim.  Didn't anybody teach you that one sample doesn't prove anything, but one counter example dis-proves all.  Go back and look at your original post.  You categorically make a general statement that I have been able to disprove.  And in the process, you also indirectly call out amplifier manufacturers.  Tell you what, make the same statement on the Bryston circle, or Nuforce, or even Modwright, and see what you get as a response.  Since you tested for Threshold, how did Nelson's amps act?

Yeah, tubes do have higher voltage rails, and, as a rule, therefore higher energy storage.  So what?  Mark Levinson once made an amp that could weld steel plates together, and it was only rated at 25 watts!  Few tube amps are capable of pushing the current of some of the big SS amps (those pesky OTs again!)

And as far as what salesmen do or don't know, since you don't know me, you don't know squat about my background.  Just a hint, you're barking up the wrong tree.

[Freo-1]

Back then it was "American" made, now it's all made in China. I try and buy American whenever I can. Mostly though, I avoid stuff that's been made in China, not because I'm anti Chinese, but because most Chinese goods are crap. Unfortunately it's getting harder and harder to find anything that isn't made in China. Anyway, I always check for country of origin before making a purchase.

Well, your assertions may have been true some years ago, but do not think this is true today.  The Chinese now make some pretty impressive audio equipment, and they seem to be the only ones who can make a current KT88 that lasts more than a couple hundred hours without shorting out.

Check out components from companies such as Eastern Electric, and you will see a high quality, well made product that holds it own against anything made at or slightly above it's price point. 

Quality control comes and goes in cycles.  Years ago, Japanese made items were considered low rent.  By the 90's, Japan was equated with quality.  Look at Korean cars, and one sees the same cycle.

[Æ]

Well, your assertions may have been true some years ago, but do not think this is true today.  The Chinese now make some pretty impressive audio equipment, and they seem to be the only ones who can make a current KT88 that lasts more than a couple hundred hours without shorting out.

Check out components from companies such as Eastern Electric, and you will see a high quality, well made product that holds it own against anything made at or slightly above it's price point. 

Quality control comes and goes in cycles.  Years ago, Japanese made items were considered low rent.  By the 90's, Japan was equated with quality.  Look at Korean cars, and one sees the same cycle.

I remember some of the Japanese stuff from forty years ago. . . it was bad and I mean real bad. Even worse than the Chinese stuff of recent decades.

Yes, you are correct, but I still shy away from Chinese products. I've seen the insides of many other products, not just electronics. Ever go to Harbor Freight Tools?

[timind]

Be advised I removed one of the postings by AE in this thread. Please keep the discourse civil. Also, this is not a forum to debate ss vs tubes.

[Freo-1]

Be advised I removed one of the postings by AE in this thread. Please keep the discourse civil. Also, this is not a forum to debate ss vs tubes.

Roger, WILCO.

Warm sound is generally asscoiated more with valves than solid state, hence the possible discussion of valve amps.  However, I have a small collection of Threshold Amps (2- S300 amps , 1-S200 amp, 1-SA/3, and a 400A).  All amps have been restored, and the 400A was completely re-done with ALL new components.  They all sound wonderful, and for solid state, exibit a warm sound compared to other solid state amps I've heard or owned over the years. 

To me, warm sound denotes a midrange that slightly brings the human voice, mid bass, and mid range in general out just a bit from the overall frequency response.  The effect results in sounding a "bit more live" and less hi-fi like.