Tube Amplifiers and your opinions.

[Harpo]

As a DIYer do you feel any pull towards processing to get attractive "tube sound" in an understood and controlled manner? This isn't intended as a negative criticism given it would be a much less interesting hobby if we all derived fun from the same things. Just curious about the attraction of tubes for those that are wired up differently to me.

Great question! I often see products advertising "tube sound" (such as the "Hybrid Tube Amps" at PE) and could never understand the appeal. I think many purchasers do not realize this is not a tube amp, though it seems to be a good product in it's own right. But emulation is always a compromise, not an end game.

So, no, I personally have no interest in products that emulate tubes. A good correlation would be the synthesizer industry. Synthesizers were originally all analog, then became sampling/digital, then became digital emulation of analog, and now the most highly regarded are real analog again. There's just no substitute for the real Moog/Hammond/Mellotron sound. The same goes for piano imo.

Cost will always be a factor, but a tube setup need not be expensive. I see PE now offers a real tube amp (the 230-265) which I think would be capable of driving the right speakers. The addition of a 2x10w tube amp to PE's lineup would be great, as would adding a subcategory of drivers/speakers suitable for use with such amps.

[AEIOU]

But they sure are purdy!

[djg]

Too bad that kit is NLA. Tube Depot sells some other kits that have received poor reviews.

[andy19191]

Great question! I often see products advertising "tube sound" (such as the "Hybrid Tube Amps" at PE) and could never understand the appeal. I think many purchasers do not realize this is not a tube amp, though it seems to be a good product in it's own right. But emulation is always a compromise, not an end game.

So, no, I personally have no interest in products that emulate tubes. A good correlation would be the synthesizer industry. Synthesizers were originally all analog, then became sampling/digital, then became digital emulation of analog, and now the most highly regarded are real analog again. There's just no substitute for the real Moog/Hammond/Mellotron sound. The same goes for piano imo.

There certainly seems to be no substitute for the The Real Thing for those that are attracted to tube amplifiers. However there is nothing to suggest this is solely to do with the sound given the physics and demonstrations of some emulations being audibly indistinguishable from The Real Thing from listening alone. Of course when enjoying listening to music with our hi-fis what we perceive involves more than the sound waggling our eardrums. Perhaps one of the characteristics of those that like tubes is a belief that tube sound cannot be successfully emulated which then leads to the tube experience not be successfully emulated when listening to the hi-fi? Just a thought.

Cost will always be a factor, but a tube setup need not be expensive. I see PE now offers a real tube amp (the 230-265) which I think would be capable of driving the right speakers. The addition of a 2x10w tube amp to PE's lineup would be great, as would adding a subcategory of drivers/speakers suitable for use with such amps.

This is another baffling aspect of speaker DIY folk being attracted to low power tube amplifiers. The Right Speakers will be required to be large and high sensitivity leading to the inclusion of some of the resonant characteristics of PA speakers. The acceptance of a drop in speaker quality in order to use tube amplifiers is strange for those with a strong interest in speakers. It is also strange in that it is an example of the tail wagging the dog given that an interest in speakers would usually lead to an appreciation that speakers contribute much more to perceived sound quality than amplifiers (or more strictly reasonably linear amplifiers!).

Again not bashing those that like tube amplifiers just find it a bit baffling among DIY speaker folk. Mind you I find the appeal of wide band drivers strange, and vinyl records (unless they contain a recording I want to hear), and expensive cables, and expensive DACs, and... Perhaps the problem is that I am an old fashioned high fidelity enthusiast rather than a modern audiophile and I grew up with records and tubes in the home and used hardware like DACs and cables simply as tools for the day job. Although I think I can see some of the appeal of tubes there seems to be something missing that makes it large enough to work for some. Interesting.

[fpitas]

My only comment is that people do buy tube amp kits, for whatever reason, and many of those kits are shoddy and/or unsafe. You'd be doing the hobby world a favor to sell something that gives reasonable value and of course, passes UL safety, EC etc.

[djg]

Too bad these days selling kits involving wiring 120 VAC to anyone with the money is a sure way to get sued. Not sure PE wants that particular headache.

And Amazon is full of little Chinese things with tubes sticking out the top. I can't imagine PE coming up with any new Chinese sourced item.

[Harpo]

There certainly seems to be no substitute for the The Real Thing for those that are attracted to tube amplifiers. However there is nothing to suggest this is solely to do with the sound given the physics and demonstrations of some emulations being audibly indistinguishable from The Real Thing from listening alone. Of course when enjoying listening to music with our hi-fis what we perceive involves more than the sound waggling our eardrums. Perhaps one of the characteristics of those that like tubes is a belief that tube sound cannot be successfully emulated which then leads to the tube experience not be successfully emulated when listening to the hi-fi? Just a thought.

I don't doubt that the characteristics of tube sound can be emulated, I just see no reason for it. I don't see anyone offering a tube amp that emulates "solid state sound", and I think that speaks volumes. I also don't see any meat lovers offering hamburger concoctions that taste "just like vegetables", but there's plenty of vegan burgers out there claiming they taste "just like meat".

This is another baffling aspect of speaker DIY folk being attracted to low power tube amplifiers. The Right Speakers will be required to be large and high sensitivity leading to the inclusion of some of the resonant characteristics of PA speakers. The acceptance of a drop in speaker quality in order to use tube amplifiers is strange for those with a strong interest in speakers. It is also strange in that it is an example of the tail wagging the dog given that an interest in speakers would usually lead to an appreciation that speakers contribute much more to perceived sound quality than amplifiers (or more strictly reasonably linear amplifiers!).

We're not necessarily "attracted" to low power amps (though SE amps are said to be the purest sound), we just can't all afford a McIntosh. Personally, I just wanted to get my feet wet in the tube realm - and now I prefer the simplicity and purity of a single power tube/channel. 2x10w is more than enough for me, I see no reason to upgrade. In fact, I just ordered a 230-265 (2x2w) to do some experimentation!

Concerning speakers, I need clarification on your comments. I can't see where selecting drivers with a high sensitivity involves lower quality or strange resonant characteristics. Please elaborate, and bear in mind I'm no expert.

[Unbiasedsound]

There is a iisshiit load of tube amps on the market ranging from very cheap to super expensive. Like with any audio component there will be good ones and bad ones. The three main goals for any product is cost, reliability and performance. Nail those three things down and you are good to go. If I had the money I would buy Thomas Gallion tube amp.

[andy19191]

I don't doubt that the characteristics of tube sound can be emulated, I just see no reason for it. I don't see anyone offering a tube amp that emulates "solid state sound", and I think that speaks volumes.

Tube amplifiers audibly distort hence "tube sound" whereas competent solid-state amplifiers are high fidelity and don't audibly distort hence there is no characteristic sound. It is possible to use tubes to create amplifiers that are linear enough not to audibly distort in use but it is largely pointless given all the issues with tubes that lead to them becoming obsolete for anything other than boutique uses.

We're not necessarily "attracted" to low power amps (though SE amps are said to be the purest sound), we just can't all afford a McIntosh. Personally, I just wanted to get my feet wet in the tube realm - and now I prefer the simplicity and purity of a single power tube/channel. 2x10w is more than enough for me, I see no reason to upgrade. In fact, I just ordered a 230-265 (2x2w) to do some experimentation!

​
How on earth can you associate purity with something that distorts grossly? SETs might be associated with rich and colourful perhaps but pure? It looks like the old marketing trick of taking the biggest negative and turning it on it's head like adverts for airlines showing passengers blissfully relaxing in their seats.

Concerning speakers, I need clarification on your comments. I can't see where selecting drivers with a high sensitivity involves lower quality or strange resonant characteristics. Please elaborate, and bear in mind I'm no expert.

In order to get high efficiency the laws of physics dictate that cones need to be large and light. This means they will resonate audibly in the manner of PA speakers. In order to get high fidelity the resonances need to be reduced which is achieved by making the cones thicker, stiffer and damped. This makes them heavier reducing efficiency. The increased power available with solid state was a major factor in allowing speakers to be less resonant and increase sound quality. Technical/studio sound quality that is rather than "subjective"/audiophile attractive distorting sound quality.

[PWR RYD]

Tube amplifiers audibly distort hence "tube sound" whereas competent solid-state amplifiers are high fidelity and don't audibly distort hence there is no characteristic sound. It is possible to use tubes to create amplifiers that are linear enough not to audibly distort in use but it is largely pointless given all the issues with tubes that lead to them becoming obsolete for anything other than boutique uses.


​
How on earth can you associate purity with something that distorts grossly? SETs might be associated with rich and colourful perhaps but pure? It looks like the old marketing trick of taking the biggest negative and turning it on it's head like adverts for airlines showing passengers blissfully relaxing in their seats.



In order to get high efficiency the laws of physics dictate that cones need to be large and light. This means they will resonate audibly in the manner of PA speakers. In order to get high fidelity the resonances need to be reduced which is achieved by making the cones thicker, stiffer and damped. This makes them heavier reducing efficiency. The increased power available with solid state was a major factor in allowing speakers to be less resonant and increase sound quality. Technical/studio sound quality that is rather than "subjective"/audiophile attractive distorting sound quality.

Why do you keep posting in this thread? You are not contributing anything useful, just preaching your distain for tube amps.

[andy19191]

Why do you keep posting in this thread? You are not contributing anything useful, just preaching your distain for tube amps.

I am interested in why people are attracted to tube amplifiers and the chat with Harpo has been helpful in this respect. I have no disdain for tubes having grown up with them and, as mentioned earlier, considered using one for the control circuitry of a plasma tweeter. They are simply obsolete technology like records and record players and what keeps them going has nothing to do with engineering or technical performance and everything to do with people. I find that interesting within the context of the hobby.

[TN Allen]

"They are simply obsolete technology like records and record players and what keeps them going has nothing to do with engineering or technical performance and everything to do with people."
(The italics are my change.)

With all due respect, this is an interesting perspective, but, isn't engineering all about people using technology?

[MisterD]

I guess I'm in the minority here, but I've recently switched over to tube for my stereo music pleasure. I purchased a Chinese EL34 based 2x10w and I couldn't be happier. Single input, gain control only, and I absolutely love the sound it gives me.

As far as amps are concerned, simplicity is the key. I'd avoid the tube-preamp/transistor-power kind you currently offer, they're just a gimmick to a true tube enthusiast. I would instead suggest very simple low power single end designs, perhaps an EL34 and even a 300B version. A reasonably priced 300B would have tube folk flocking to your door!

From a merchandising standpoint, my new tube amp is the very reason I just spent over $1000 at PE for drivers to build new more efficient 3-ways, thread here. This could be a cross merchandising opportunity too, since you have a great selection of high efficiency drivers.​

I have one of those cheap Chinese EL34 SEP amps and have to agree; for the $350 or so shipped, they sound VERY good. BUT - other (more expensive) tube amps sound better. Nice things about my “Oldchen” which is also sold under a couple other names, are that they’re cheap, reliable, and have a clear, uncluttered midrange. A really nice midrange. Highs and bass are just OK.

A really good push-pull however, offers a good midrange along with better highs and powerful, quick bass. Of course, much has to do with speaker efficiency. With inefficient speakers, don’t bother with single-ended.

[andy19191]

"
With all due respect, this is an interesting perspective, but, isn't engineering all about people using technology?

Engineering is broadly the application of science and maths to solve problems. This can be a bit disconcerting for some when they go to university to study engineering and find out just how much applied maths is involved. Many decades ago on my undergraduate engineering course 50% of the students dropped out in the first year with applied maths being the main reason. People that use technology are perhaps more likely to be technicians though it does rather depend on what one means by use technology and how it is being used. One can recognise an engineer in a particular field by their knowledge of the relevant science and maths and their ability to use it to reason about what is going on and solve problems directly using it. Technicians tend to lack this knowledge which takes years of study to acquire and instead rely on experience, documented procedures, experiments and similar to pull together information to make decisions and solve problems.

I have recently registered a github account to discuss loudspeaker engineering but am still dithering about whether to write for engineers or to try to write for (some) speaker DIY folk. The latter is more challenging because it requires not only getting across the engineering but also the relevant scientific principles (not too bad) and maths (more difficult) on which it is based. My chat with Harpo is not unrelated to trying to assess who may or may not be in the audience for such a site.

[MisterD]

I don’t believe that tube amplifiers ever became “obsolete technology” as far as sound quality. Tubes themselves became obsolete because of production cost vs semiconductors as well as their greater size, weight and - appeal to consumers. You may think you see better electronic measurements from quiet transistor amps - but how much unmeasured musical sound are you not hearing?

Before anyone says or may think that I’ve never heard a good transistor amp - I’ve had a fairly “liquid” sounding Krell KSA-100 MkII for years now. It’s a full class A making 100wpc into an 8 ohm load - and supposedly it’ll drive 1 ohm loads at 800wpc. Aside from amazing power which dims the lights when switched on and heats the room like it’s supposed to double as a heater.., it’s a really nice sounding amp - but it’s not as pleasing (to my ears) as my 60 year old Harmon-Kardon tube amp.

[andy19191]

You may think you see better electronic measurements from quiet transistor amps - but how much unmeasured musical sound are you not hearing?

To clarify, you are referring to sound created by tube amplifiers but not transistor amplifiers that we can hear but cannot measure?