Tubes.....and the Jerks that use them.

[GordonW 10+ year member]

Dismissing tube amps as "higher distortion" and "colored" is a simplistic argument. And as such, it's frequently false.

When comparing two amps, there's a very useful test called "distortion spectrum test". Basically, it's NOT only HOW MUCH distortion, it's HOW MANY harmonics the distortion typically shows up in.

The human ear is very tolerant of low-order harmonics (ie, second, third, fourth harmonics)... but higher order harmonics (8th, 9th, 10th, and so on) can be heard/sensed in VERY SMALL quantities... and are usually regarded as a "harsh" or "gritty" sound.

While tube amps have more second and third harmonic distortion, the distortion spectrum goes VERY RAPIDLY to zero. It's rare to have significant higher harmonics present, at anything other than HARD CLIPPING. OTOH, there's LOTS of solid state amps (fortunately, not as much as it was, even 5 to 10 years ago) that exhibit SIGNIFICANT, AUDIBLE amounts of higher harmonics, EVEN AT LOW LISTENING LEVELS, due to non-linearities in the transistors themselves that CANNOT be completely corrected by feedback. Feedback is good at correcting lower harmonics (lower frequency, less bandwidth required by the feedback circuit) than they are at correcting higher harmonics (where the frequencies sometimes EXCEED the bandwidth that the feedback loop can correct, due to time delays in the return path).

As I mentioned, there ARE better semiconductors now... and REALLY GOOD solid state designs (high-end stuff, for the most part) can be VERY clean/transparent/smooth sounding. But MANY amp designs out there (especially on mid-priced stuff) are based on older technology... and still have some of the same problems...

So, don't fall into the trap of "it measures better, it MUST sound better". You've gotta be careful of WHAT they're measuring, and HOW they're measuring it!!

Regards,

Gordon.

 

[desertheat 10+ year member]

Anyone who has even barely delved into the Audiophile realm will quickly learn that these people that love that "warm" sound of tubes are totally conceited.
It's like these people *cough* Jack Frost *cough* think that they know something that 90% of all other audio connoisseurs don't. The truth is that Tube fans are like Corvette owners. They think they own the ultimate driving machine and thus their shit don't stink, but in reality, they are too poor to step to a real machine and are thus left to rule the trailer park.

One day maybe they'll see, that there's more to audio that disgustingly high noise floor and embellished recreation of recordings....//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

*LOL* hey butt nugget, I am a tube guy as well //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif hahahaha. All good. I am one of the rare ones that like tubes because...

#1 they are classic and are more of an art form than other styles of amplifiers or equipment...

#2 certian styles of tubes coupled usually to very high efficiency speakers sound quite amazing and can have bass and sexy top end if built / designed correctly.

#3, I like projects, older tube amps make very cool and fun projects to restore and are a great conversation item

#4 the warm glow gives me a warm and fuzzy hahaha.

In car, I run solid state and will only run solid state. In my HT, of course.. solid state...

In my future listening room / currently my office you will find a beatiful pair of OTL's coupled to a line array.

It is not so much a status or snob thing... but kinda a refined item... Like a fine wine, a perfectly cooked steak or ripping up the mountain corners in any sports car, high end or not. Looking at a tube amplifier and listening to a good setup always brings a nice feeling to things... makes the whole experience feel more worthwhile. With car audio or a standard home stereo... You walk around.. doing things... driving and listening.. with a real audiophile setup you can sit for hours changing cd's or records listening and enjoying... You just tend to listen more if you invest in a high end setup or repaired / built your own amp... just my perspective. Tube amps are the origin of true home audio, and they have been modified and changed over time to sound as good if not better than solid state.

But yeah.. I see your point... some people brag non stop about there newest 3 watt super tube, harmonically balanced uber amp that just cost them $6K dollers per side and that nothing else could sound better. Those guys piss me off and usually there stuff sounds like crap coming from an alarmclock haha!

 

[GordonW 10+ year member]

If anyone wants to talk reliability, I can only mention:

a) Set of McIntosh MC30 monoblock tube amps, and the accompanying C-20 tube preamp... bought by the ORIGINAL OWNER in 1961 (!) and were STILL WORKING when they were removed (and replaced with MODERN tube amps, he wanted remote control and more power) in 2004. And he used them an AVERAGE of 8 hours EVERY DAY (he was a dentist, and had his practice in his house, where the system provided background music in his office ALL DAY every day).

b) My Harman-Kardon Award 300 integrated amp. Got it from a guy who was going to throw it away... only thing wrong with it, after THIRTY EIGHT YEARS, was a bad volume control, which had caused an overload in one channel, which used up one of the output tubes. A new volume control, two new tubes (I replaced them in a matched pair) and two new coupling caps (for insurance sake), and it's working LIKE NEW. Literally, thirty bucks worth of parts, and an hour to fix it. It now sits in my living room, and it provides a lot of fun for me and my friends to listen to.

3. My former (I sold it) Magnavox AMP185 tube amp... got it out of a console. Made in 1960. Replaced ONE RESISTOR, and it was perfect. All the tubes measured LIKE NEW on three different tube testers.

How many people seriously think ANY of the modern "mass-market" solid state stuff is going to be working 40 years from now?

Regards,

Gordon.

 

[thylantyr 10+ year member]

OTL's coupled to a line array.

Line array? cool... where's the pics ?

 

[thylantyr 10+ year member]

Dismissing tube amps as "higher distortion" and "colored" is a simplistic argument. And as such, it's frequently false.
When comparing two amps, there's a very useful test called "distortion spectrum test". Basically, it's NOT only HOW MUCH distortion, it's HOW MANY harmonics the distortion typically shows up in.

The human ear is very tolerant of low-order harmonics (ie, second, third, fourth harmonics)... but higher order harmonics (8th, 9th, 10th, and so on) can be heard/sensed in VERY SMALL quantities... and are usually regarded as a "harsh" or "gritty" sound.

While tube amps have more second and third harmonic distortion, the distortion spectrum goes VERY RAPIDLY to zero. It's rare to have significant higher harmonics present, at anything other than HARD CLIPPING. OTOH, there's LOTS of solid state amps (fortunately, not as much as it was, even 5 to 10 years ago) that exhibit SIGNIFICANT, AUDIBLE amounts of higher harmonics, EVEN AT LOW LISTENING LEVELS, due to non-linearities in the transistors themselves that CANNOT be completely corrected by feedback. Feedback is good at correcting lower harmonics (lower frequency, less bandwidth required by the feedback circuit) than they are at correcting higher harmonics (where the frequencies sometimes EXCEED the bandwidth that the feedback loop can correct, due to time delays in the return path).

As I mentioned, there ARE better semiconductors now... and REALLY GOOD solid state designs (high-end stuff, for the most part) can be VERY clean/transparent/smooth sounding. But MANY amp designs out there (especially on mid-priced stuff) are based on older technology... and still have some of the same problems...

So, don't fall into the trap of "it measures better, it MUST sound better". You've gotta be careful of WHAT they're measuring, and HOW they're measuring it!!

Regards,

Gordon.

Some thoughts that derail your post.

ABX test, people will fail the amp test. No matter if the amp is 20 years old,

tube, solid state, class D. As long as the 'apples to apples' test is calibrated

properly. That doesn't say that you can't hear a different overdriven, but

over driving amps is counterproductive right? lol

RE: Semiconductor issue. Give me some 20+ year old lateral mosfest or

TIP35 transistors and I can show you some great amp designs that hold their

own today. Give me an ancient 5532 opamp and compare it to a modern

$25 opamp, and you will fail the blind test.

LOL....

 

[GordonW 10+ year member]

Some thoughts that derail your post.
ABX test, people will fail the amp test. No matter if the amp is 20 years old,

tube, solid state, class D. As long as the 'apples to apples' test is calibrated

properly. That doesn't say that you can't hear a different overdriven, but

over driving amps is counterproductive right? lol

Most people seem to misunderstand the applicability of an ABX test.

Even David Clark, the INVENTOR of the modern ABX test, had to admit to Gary Galo at the 1991 AES meeting, that an ABX test CANNOT rule out differences between equipment... only that the ABX can only CONFIRM a difference. In other words, there is NO WAY an ABX test can prove a negative result. These are FUNDAMENTAL LIMITATIONS of the ABX methodology.There are quite possibly differences that are beyond the scope of the limited test specifications. These limitations of ABX testing have been known in audio engineering circles, for at least the last 16 years.

Besides, the "apples to apples" test requirements fly in the face of reality anyhow. NOT ALL AMPS actually HAVE the same frequency response... and once you put an EQ in line with one amp to compensate for another, all bets are off anyway, due to the addition of the "sonic signature" of the EQ itserlf. And ,the difference between noise floor behaviour is not something to be IGNORED, but one of the PRIME REASONS people pick one amp design over another.

In addition, the "no clipping" requirements of the ABX test methodology mentioned above, fly in the face of VIRTUALLy ALL real-world music listening. Unless you have THOUSANDS of watts and/or VERY EFFICIENT speakers (ie, 95 dB sensitivity or higher, you WILL instantaneously clip MOST ANY amp on transients. Most "live" music (ie, recordings without excessive compression) have 30-40 dB "crest factor"... ie, if you're listening to an average of 80 dB, you have PEAKS of 110 dB or higher. It's not PERCIEVED to be that loud on average... because, the average level IS only around 80 dB. But, the AMP sees that 110 dB peak as 1000X the power demand, of the 80 dB nominal level... and voila, momentary clipping.

In short, one of the fundamental problems in modern society is the tendency to over-simplfy issues... which is bad enough when it's simply politics or day-to-day social behaviour. But when such over-simplification invades science, it's a bad day for science...

Regards,

Gordon.

 

[thylantyr 10+ year member]

You like falling into my trap //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

In addition, the "no clipping" requirements of the ABX test methodology mentioned above, fly in the face of VIRTUALLy ALL real-world music listening. Unless you have THOUSANDS of watts and/or VERY EFFICIENT speakers (ie, 95 dB sensitivity or higher, you WILL instantaneously clip MOST ANY amp on transients. Most "live" music (ie, recordings without excessive compression) have 30-40 dB "crest factor"... ie, if you're listening to an average of 80 dB, you have PEAKS of 110 dB or higher. It's not PERCIEVED to be that loud on average... because, the average level IS only around 80 dB. But, the AMP sees that 110 dB peak as 1000X the power demand, of the 80 dB nominal level... and voila, momentary clipping.

In the real world you say.

"you WILL instantaneously clip MOST ANY amp on transients. "

and

"Most "live" music (ie, recordings without excessive compression) have 30-40 dB "crest factor".

Ok, cool. I have 12 proamps, 62kw of power/headroom. That satisfied the

requirement. I could buy 62kw of tube amplification, but image the costs. LOL

Since most people have 1w - 10w tube amps, the criteria is not met and the

tube amp isn't good.. based on your claim.... But, on the other hand, efficient

speakers offsets the low power and it can offer good performance. These efficient

loudspeaker designs are limited. Since the loudspeaker gives you the most impact on

SQ, limiting your choice on loudspeaker designs is counter productive. A person should

have access to all the loudspeaker designs to properly find satisfaction, then find the

suitable amplifier second.

You said;

OTOH, there's LOTS of solid state amps (fortunately, not as much as it was, even 5 to 10 years ago) that exhibit SIGNIFICANT, AUDIBLE amounts of higher harmonics, EVEN AT LOW LISTENING LEVELS, due to non-linearities in the transistors themselves that CANNOT be completely corrected by feedback.

Considering that ABX amplifier testing has been done for many many years,

tube vs. solid state, in their 'unrealistic' operating mode of 'not clipping', you

call this 'low listening levels', then the ABX test would be an easy pass as the SS

amp would be detected by audible distortion.... but so far, it has not. This implies that the human ear isn't as good as electronic test gear when it comes to

detecting low level distortion.

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

My views are different for using tube amps to creat sonic special effects, ie guitar players who overdrive the amps, etc.

 

[Beat_Dominator 5,000+ posts]

//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif look at what JimJ started.

 

[desertheat 10+ year member]

OTL's coupled to a line array.
Line array? cool... where's the pics ?

I love it when someone says "line array" and the smmmaaarrrtttt folks come ah running *LOL*!!! I am actually building it slowly, I tried a design from the old zalytron book but was not happy with it.. To dry for my taste.. I am currently seeking somthing new which is why I made the reference to my "future listening room". I will be useing a pair of t16 otls from trancendent for power.... the head and the pre are still undecided but I may end up with the grounded grid preamp as well from trancendent. I have found Bruces writings facinating!

I am no mega audio guru as some of you may be but I have been around a very very long time in this biz, more on the political side of this. But I listen allot and have a passion for it still. This system will be my dream system and I cannot wait to finish it. I am not rich and the most of my funds go to my show car, but it is almost done so now time to re-direct funds.... If any of you mega guru's wanna send some advice for the array, please feel free. I have been talking with a guy at madisound for ideas and searching the web.

I will have 40w at 8ohm to work with so I have quite a few options... Time will tell!

 

[Beat_Dominator 5,000+ posts]

I have a preamp for sale Desert //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

I have faith in your tastes though man. If only my setup was in a more dedicated listening room, then I'd have you come take a listen, and you might not care about line arrays anymore //content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif

 

[desertheat 10+ year member]

I will listen to anything anyplace, does not matter the room or the setting, I just wanna hear what things sound like. Pm me with what ya have..?

 

[Beat_Dominator 5,000+ posts]

Will do //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[joetama 5,000+ posts]

What do you have now Beat?

 

[JimJ 5,000+ posts]

He has the preamp he was going to sell to me //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I'm still kinda debating it...but Classe has a couple things I'm considering as well...and the B&K looks good for the price too, but the nerds on AudioAsylum dissed it, lol.

 

[Beat_Dominator 5,000+ posts]

I'll sell you my Classe pre Jimbo....for a healthy profit //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif