Wanting To Learn About Tube Amps

[Thrill Killer]

I'm NOT asking for Recs or Tech Help. As I'm not buying right now. Nor do I need tech help. As I have no tube amp to need help with.

I want to learn about Headphone Tube Amps.

1. Differences in amp designs
2. Why 1, 2, 3, 4, or 5 tubes in some amps
3. What makes one amp better than another outside of Wattage
4. Design philosophy?
5. Hybrid tube amps: Solid state w/tubes or Transistors/Resistors w/tubes

I just want to learn about them to ultimately purchase one.

I've owned SS amp from

1. Schiit x2
2. S.M.S.L. x2
3. Topping x1
4. JDS x1 after 2 weeks it gave me magic smoke instead of mWs

Various lines and wattages. But want to step up to tubes. My current amp is Great. And I'm not getting rid of it when I buy the tube amp. It will stay in my set up. My Pre-Dac is staying also. AAA THX-887 & RME ADI-2. Plus Arya Stealth and Arya Organic arriving this week. And want to start tubes with that.

So, if anyone know of any sites, forums, links, etc. that I can learn about headphone tube amps, I'd appreciate it. Then I can make an informed decision of what type and brand of tube amp to ultimately purchase.

 

[MaxwellsEq]

I'm NOT asking for Recs or Tech Help. As I'm not buying right now. Nor do I need tech help. As I have no tube amp to need help with.

I want to learn about Headphone Tube Amps.

1. Differences in amp designs
2. Why 1, 2, 3, 4, or 5 tubes in some amps
3. What makes one amp better than another outside of Wattage
4. Design philosophy?
5. Hybrid tube amps: Solid state w/tubes or Transistors/Resistors w/tubes

I just want to learn about them to ultimately purchase one.

I've owned SS amp from

1. Schiit x2
2. S.M.S.L. x2
3. Topping x1
4. JDS x1 after 2 weeks it gave me magic smoke instead of mWs

Various lines and wattages. But want to step up to tubes. My current amp is Great. And I'm not getting rid of it when I buy the tube amp. It will stay in my set up. My Pre-Dac is staying also. AAA THX-887 & RME ADI-2. Plus Arya Stealth and Arya Organic arriving this week. And want to start tubes with that.

So, if anyone know of any sites, forums, links, etc. that I can learn about headphone tube amps, I'd appreciate it. Then I can make an informed decision of what type and brand of tube amp to ultimately purchase.

I've been thinking about your question. It's not that easy to answer because of the constraints you put on us.

I want to learn about Headphone Tube Amps

I'm NOT asking for Recs or Tech Help. Nor do I need tech help

Your numbered questions suggest you want to understand the underlying choices designers make and why they make them.

Firstly all electronic design is a compromise and often cost or size drives some compromises. An amplifier with 20 tubes would be heavy and hot, but a similar design done with 20 FETs would be much cooler, smaller and lighter.

A tube is just a device which can achieve gain (input is multiplied by some value). In that regard it's no different than a bipolar transistor or field effect transistor. In general it operates at much higher voltages than transistors. It has no "magic". But the size, weight and heat mean designers tend to go for fewer "active" components, which can lead to compromises.

If you want to study designs, there are many free resources online. You may want to search DIYaudio. Here is a list of out of copyright books covering the subject.

 

[Jim Taylor]

But want to step up to tubes.

It seems from your post that you are a fairly young person, and have not had a great deal of exposure to tube gear. I'm not young, I've had more exposure to tube gear than I like in the '50s and '60s, and I was greatly impressed in the '70s when I switched over to solid state gear. I don't consider tube gear to be a "step up", and I'll explain why.

This doesn't mean that I'm trying to categorically dissuade you from tube gear, but I've noticed a couple things in how tube gear is different nowadays from "back in the day".

1) Tube cost. I no longer use tubes, but I have acquaintances who do. For one thing, they change tubes more often that what I remember from long ago. And you have asked us about headphone tube amps with multiple tubes. If you choose carefully, you can swap out a set of tubes for not-so-much money, BUT ... some tube sets are quite expensive, and you may need to pay this recurring cost quite often. So be careful in your choice! It may be more expensive than you think, in the long run.

2) I hear complaints about "bad tubes" more often than I consider tolerable. It's my impression that tube manufacturing is not to as high a standard compared to 60-70 years ago. This not only affects the design you purchase, but can greatly affect the outcome of "tube rolling", if you decide to go down that rabbit hole.

3) Design agenda. In the '50s and '60s, tube gear was aimed at what was considered the universal goal at the time; accurate reproduction. Flatter frequency response, lower noise and greater circuit stability were considered necessary goals.
That's not necessarily true any more. Some designers still have these goals, but some no longer consider neutrality and accuracy to be worthy goals. Instead, they concentrate on affected sound, with higher-distortion bass and frequency response that varies quite a bit from flat. Not all headphone amps fall into this category, and possibly not as many as power amps for speakers. The thing is, how do you know which are in this category without purchasing the amp and trying it? After all, someone here who gives you advice based on their 'phones may mislead you compared to the characteristics of your 'phones, simply because yours and theirs have vastly differing impedance profiles.

Do you really want to start playing the game of "not this one, not that one and not the other one" in regard to tube products? This is one of the big criticisms I have against tube gear ... it's so difficult to identify the neutral designs from the affected designs.
And if you DO want a unit that has an affected sound, how can you identify which unit has the particular affected sound that you find desirable? (And then, when you find it, you may buy new 'phones and have to start all over again.)

In short ... if you want accurate and consistent reproduction, stay with your solid state devices. OTOH, if you want affected sound, be prepared to enter a swamp through which you will slog, maybe for years, with no guarantee of success.

Your choice.

 

[gwing]

Tube gear isn't a "step up" but an older way of doing things. Cheap modern tube gear isn't

I'm NOT asking for Recs or Tech Help. As I'm not buying right now. Nor do I need tech help. As I have no tube amp to need help with.

I want to learn about Headphone Tube Amps

1. Differences in amp designs

If you are really interested in Tube Amps and designs that is a very deep subject. I recommend "Valve Amplifiers" by Morgan Jones which is a relatively modern publication and much easier reading than some of the more classic reference material.

1. Why 1, 2, 3, 4, or 5 tubes in some amps

Different circuit designs require different numbers of tubes.

1. What makes one amp better than another outside of Wattage

Design, build, layout and component quality, especially the quality of the transformers.

1. Design philosophy?
2. Hybrid tube amps: Solid state w/tubes or Transistors/Resistors w/tubes

Usually these aren't proper tube amps but (often cheap) modern solid state amps with a couple of tubes stuck into the design for marketing reasons. They may well colour the sound in a way you like and do look pretty for not that much money so are a not such a bad idea for a bit of audio fun. They bear little constructional similarity with a traditional valve amp.

I just want to learn about them to ultimately purchase one.

I've owned SS amp from

1. Schiit x2
2. S.M.S.L. x2
3. Topping x1
4. JDS x1 after 2 weeks it gave me magic smoke instead of mWs

Various lines and wattages. But want to step up to tubes. My current amp is Great. And I'm not getting rid of it when I buy the tube amp. It will stay in my set up. My Pre-Dac is staying also. AAA THX-887 & RME ADI-2. Plus Arya Stealth and Arya Organic arriving this week. And want to start tubes with that.

So, if anyone know of any sites, forums, links, etc. that I can learn about headphone tube amps, I'd appreciate it. Then I can make an informed decision of what type and brand of tube amp to ultimately purchase.

For a forum try here: DIY Audio Forum .

 

[DVDdoug]

to ultimately purchase.

Why???

Tubes are outdated (for many decades). It's more difficult and more expensive to make a tube amp (especially a good one), they are less energy efficient, and the tubes eventually deteriorate and die.

A good amp won't have any particular "sound". The job of a hi-fi amp is simply to amplify (ignoring tone controls). But if a tube amp has "tube sound" it's going to sound different from another tube amp and you'll have to listen and decide for yourself if you like it. There isn't "one tube sound".

A McIntosh tube amp will sound "perfect", just like most solid state amps but they are crazy expensive. There are more affordable good tube amps but I just happen to know that McIntosh has made good amps since the tube-days when most other amps didn't measure-up.



...Guitar players tend to prefer tubes because of the way they sound when over-driven into distortion. Guitar amps aren't high fidelity and they do have a "sound" so most guitar players have their favorite guitar and favorite amp. Of course with hi-fi we are trying to avoid distortion (unless it's included in the recording as a guitar effect, etc.).

P.S.
A lot of "audiophiles" like tubes and vinyl and other vintage technology. But MOST audiophiles are nuts! This is one of the few scientific-rational audio-related resources.

 

[Curupira]

Besides the topology aspect, I highly encourage you to try Harmonic Distortion VSTs for a simulation of what a "tube" sound is. Of course, it won't replicate all aspects of a valve amp (you can't control output impedance, preference for high Z of OTL, etc), but it will show you how minor the changes from THD actually are on the perceived sound, and how people, especially in the "audiophile hobby" tend to blow things out of proportion.

A great one is the PKHarmonic VST project. from @pkane (see the ASR thread here) . It works with EQAPO. Download the 64 or 32 bit version for PK audio on the link above, depending on your OS, and run the installer. Then, go to EQAPO's configuration (or install it, beforehand), click the add button > VST plugin, then go to C:\Program Files\PKAudio\PKHarmonic64 [or wherever you installed it) and select the PKHarmonic.dll.

Open the Panel and configure the Harmonic distortion tones relative to 0dBFS (don't use positive numbers or it'll clip). While there, you can try to mimic the distortion profile of the most famous tube amps on the market by following their APx measurements. Below, I mimicked the new Schiit Valhalla 3 as per their own internal measurements:

Incidentally, I also recommend trying out the Klippel listening test for harmonic distortion, and see how far (how low) you can notice harmonic distortion added into the track, when doing it blindly. For this test, be mindful that most contemporary tube amps score -60 to -90 dB SINAD, with the predominant harmonics (H2 and H3) being in the -50 dB to - 80 dB range relative to the 0dBFS fundamental. In other words, if you can't get to below, say, -30dB, on the klippel test, the results you'll hear from any better-performing tube amp will be mostly from placebo, noise or from output impedance altering the headphone's/speaker's frequency response.

 

[Thrill Killer]

I've been thinking about your question. It's not that easy to answer because of the constraints you put on us.


Your numbered questions suggest you want to understand the underlying choices designers make and why they make them.

Firstly all electronic design is a compromise and often cost or size drives some compromises. An amplifier with 20 tubes would be heavy and hot, but a similar design done with 20 FETs would be much cooler, smaller and lighter.

A tube is just a device which can achieve gain (input is multiplied by some value). In that regard it's no different than a bipolar transistor or field effect transistor. In general it operates at much higher voltages than transistors. It has no "magic". But the size, weight and heat mean designers tend to go for fewer "active" components, which can lead to compromises.

If you want to study designs, there are many free resources online. You may want to search DIYaudio. Here is a list of out of copyright books covering the subject.

The format of this is kinda different. I had initially tried to post this to the Headphone reddit within their rules and formatting.

 

[Thrill Killer]

I've been thinking about your question. It's not that easy to answer because of the constraints you put on us.


Your numbered questions suggest you want to understand the underlying choices designers make and why they make them.

Firstly all electronic design is a compromise and often cost or size drives some compromises. An amplifier with 20 tubes would be heavy and hot, but a similar design done with 20 FETs would be much cooler, smaller and lighter.

A tube is just a device which can achieve gain (input is multiplied by some value). In that regard it's no different than a bipolar transistor or field effect transistor. In general it operates at much higher voltages than transistors. It has no "magic". But the size, weight and heat mean designers tend to go for fewer "active" components, which can lead to compromises.

If you want to study designs, there are many free resources online. You may want to search DIYaudio. Here is a list of out of copyright books covering the subject.

I did want to learn about HP amp designs, layouts, functions, etc. As I wanted to learn to make a informed decision when I do purchase one.

 

[MaxwellsEq]

I did want to learn about HP amp designs, layouts, functions, etc. As I wanted to learn to make a informed decision when I do purchase one.

OK, I get it.

What do you know about electronic design (regardless of tube or solid state)? If you understand solid state headphone amplifiers, then we can discuss what's different about tube headphone amplifiers. If you don't have knowledge about electronic design, we'd need to back up a bit and talk about gain, impedance etc.

 

[mhardy6647]

A good place to start with all things amplifier, written in the vacuum tube era.
Vacuum tube circuits are far simpler and easier to understand than solid state circuitry -- i.e., understanding vacuum tube audio circuits ain't a bad place to start, even if one's interests don't a priori include classic vacuum tube circuits.

https://www.worldradiohistory.com/BOOKSHELF-ARH/Technology/Rider-Books/Rider-201-Basic-Audio-Norman-H.-Crowhurst.pdf

 

[MaxwellsEq]

A good place to start with all things amplifier, written in the vacuum tube era.
Vacuum tube circuits are far simpler and easier to understand than solid state circuitry -- i.e., understanding vacuum tube audio circuits ain't a bad place to start, even if one's interests don't a priori include classic vacuum tube circuits.

View attachment 489952​

https://www.worldradiohistory.com/BOOKSHELF-ARH/Technology/Rider-Books/Rider-201-Basic-Audio-Norman-H.-Crowhurst.pdf

Interesting book! I'd not come across this before.

 

[Thrill Killer]

It seems from your post that you are a fairly young person, and have not had a great deal of exposure to tube gear. I'm not young, I've had more exposure to tube gear than I like in the '50s and '60s, and I was greatly impressed in the '70s when I switched over to solid state gear. I don't consider tube gear to be a "step up", and I'll explain why.

This doesn't mean that I'm trying to categorically dissuade you from tube gear, but I've noticed a couple things in how tube gear is different nowadays from "back in the day".

1) Tube cost. I no longer use tubes, but I have acquaintances who do. For one thing, they change tubes more often that what I remember from long ago. And you have asked us about headphone tube amps with multiple tubes. If you choose carefully, you can swap out a set of tubes for not-so-much money, BUT ... some tube sets are quite expensive, and you may need to pay this recurring cost quite often. So be careful in your choice! It may be more expensive than you think, in the long run.

2) I hear complaints about "bad tubes" more often than I consider tolerable. It's my impression that tube manufacturing is not to as high a standard compared to 60-70 years ago. This not only affects the design you purchase, but can greatly affect the outcome of "tube rolling", if you decide to go down that rabbit hole.

3) Design agenda. In the '50s and '60s, tube gear was aimed at what was considered the universal goal at the time; accurate reproduction. Flatter frequency response, lower noise and greater circuit stability were considered necessary goals.
That's not necessarily true any more. Some designers still have these goals, but some no longer consider neutrality and accuracy to be worthy goals. Instead, they concentrate on affected sound, with higher-distortion bass and frequency response that varies quite a bit from flat. Not all headphone amps fall into this category, and possibly not as many as power amps for speakers. The thing is, how do you know which are in this category without purchasing the amp and trying it? After all, someone here who gives you advice based on their 'phones may mislead you compared to the characteristics of your 'phones, simply because yours and theirs have vastly differing impedance profiles.

Do you really want to start playing the game of "not this one, not that one and not the other one" in regard to tube products? This is one of the big criticisms I have against tube gear ... it's so difficult to identify the neutral designs from the affected designs.
And if you DO want a unit that has an affected sound, how can you identify which unit has the particular affected sound that you find desirable? (And then, when you find it, you may buy new 'phones and have to start all over again.)

In short ... if you want accurate and consistent reproduction, stay with your solid state devices. OTOH, if you want affected sound, be prepared to enter a swamp through which you will slog, maybe for years, with no guarantee of success.

Your choice.

To me, "A step up" is from my current headphone set up. In my life I have owned MC30 x2 1959, MC100 x2 1973, MC275 1969. I'm looking for a different kind of sound. I will be keeping my ss amp. It's the same reason that us, we in the hobby switch gear. We buy gear then after awhile vend to get something else. Always tweaking, always seeking. It's a part of the hobby. I still have the 275. It's in my workshop powering some 4344s

I am starting off with the Cayin HA-3A. I PTT this morning. ETA is Friday 11/14 with my Arya Organics arriving the day before. Many serious hp hobbyist own multiple sets of cans. I was one of them. Then settled down to 1 pr open, 1 pr closed. And I will now have 2 amps. 1 ss and 1 tube.

From the help here and on other forums I have learned a lot about hp amps. Both ss and tube. I always took them for granted. You know, plug in wall , plug in cans. Thank you for your input. PS: I am in my late 60's. And have been in the hobby on a serious level since the late 70's as freshman in college.

 

[Thrill Killer]

Tube gear isn't a "step up" but an older way of doing things. Cheap modern tube gear isn't



If you are really interested in Tube Amps and designs that is a very deep subject. I recommend "Valve Amplifiers" by Morgan Jones which is a relatively modern publication and much easier reading than some of the more classic reference material.

Different circuit designs require different numbers of tubes.

Design, build, layout and component quality, especially the quality of the transformers.

Usually these aren't proper tube amps but (often cheap) modern solid state amps with a couple of tubes stuck into the design for marketing reasons. They may well colour the sound in a way you like and do look pretty for not that much money so are a not such a bad idea for a bit of audio fun. They bear little constructional similarity with a traditional valve amp.


For a forum try here: DIY Audio Forum .

To me, "A step up" is from my current headphone set up.

 

[Thrill Killer]

Why???

Tubes are outdated (for many decades). It's more difficult and more expensive to make a tube amp (especially a good one), they are less energy efficient, and the tubes eventually deteriorate and die.

A good amp won't have any particular "sound". The job of a hi-fi amp is simply to amplify (ignoring tone controls). But if a tube amp has "tube sound" it's going to sound different from another tube amp and you'll have to listen and decide for yourself if you like it. There isn't "one tube sound".

A McIntosh tube amp will sound "perfect", just like most solid state amps but they are crazy expensive. There are more affordable good tube amps but I just happen to know that McIntosh has made good amps since the tube-days when most other amps didn't measure-up.



...Guitar players tend to prefer tubes because of the way they sound when over-driven into distortion. Guitar amps aren't high fidelity and they do have a "sound" so most guitar players have their favorite guitar and favorite amp. Of course with hi-fi we are trying to avoid distortion (unless it's included in the recording as a guitar effect, etc.).

P.S.
A lot of "audiophiles" like tubes and vinyl and other vintage technology. But MOST audiophiles are nuts! This is one of the few scientific-rational audio-related resources.

Why??? Because I can afford to. It's also why I still have a TT. It's old school, it's nostalgia. I want to own different kinds of set ups. I always have over the decades.

 

[Thrill Killer]

It seems from your post that you are a fairly young person, and have not had a great deal of exposure to tube gear. I'm not young, I've had more exposure to tube gear than I like in the '50s and '60s, and I was greatly impressed in the '70s when I switched over to solid state gear. I don't consider tube gear to be a "step up", and I'll explain why.

This doesn't mean that I'm trying to categorically dissuade you from tube gear, but I've noticed a couple things in how tube gear is different nowadays from "back in the day".

1) Tube cost. I no longer use tubes, but I have acquaintances who do. For one thing, they change tubes more often that what I remember from long ago. And you have asked us about headphone tube amps with multiple tubes. If you choose carefully, you can swap out a set of tubes for not-so-much money, BUT ... some tube sets are quite expensive, and you may need to pay this recurring cost quite often. So be careful in your choice! It may be more expensive than you think, in the long run.

2) I hear complaints about "bad tubes" more often than I consider tolerable. It's my impression that tube manufacturing is not to as high a standard compared to 60-70 years ago. This not only affects the design you purchase, but can greatly affect the outcome of "tube rolling", if you decide to go down that rabbit hole.

3) Design agenda. In the '50s and '60s, tube gear was aimed at what was considered the universal goal at the time; accurate reproduction. Flatter frequency response, lower noise and greater circuit stability were considered necessary goals.
That's not necessarily true any more. Some designers still have these goals, but some no longer consider neutrality and accuracy to be worthy goals. Instead, they concentrate on affected sound, with higher-distortion bass and frequency response that varies quite a bit from flat. Not all headphone amps fall into this category, and possibly not as many as power amps for speakers. The thing is, how do you know which are in this category without purchasing the amp and trying it? After all, someone here who gives you advice based on their 'phones may mislead you compared to the characteristics of your 'phones, simply because yours and theirs have vastly differing impedance profiles.

Do you really want to start playing the game of "not this one, not that one and not the other one" in regard to tube products? This is one of the big criticisms I have against tube gear ... it's so difficult to identify the neutral designs from the affected designs.
And if you DO want a unit that has an affected sound, how can you identify which unit has the particular affected sound that you find desirable? (And then, when you find it, you may buy new 'phones and have to start all over again.)

In short ... if you want accurate and consistent reproduction, stay with your solid state devices. OTOH, if you want affected sound, be prepared to enter a swamp through which you will slog, maybe for years, with no guarantee of success.

Your choice.

I've owned many a tube amps in my time. Never rolled once. Only replaced tubes that went bad.

 

[DSJR]

I think many of us have to go the valve/tube route, at least for a while, in our journey. My take today is to go right ahead, but choose carefully and make sure you're aware of the pitfalls, costs on occasion and performance compromises in almost all domestic-audio valve designs

 

[mhardy6647]

Interesting book! I'd not come across this before.

I think it is a pretty good primer.
Crowhurst published an early, four part series on pulse-width modulation for audio amplification in Audio magazine in 1965.

Class D (PWM) amplifier archaeology

So, I'm a scientist, not a historian, but I am still fascinated by history... and I crave context. You all know that the late Sir Clive Sinclair is regarded as the purveyor of the first significant PWM amplifier products for audio. https://www.vintage-radio.net/forum/showthread.php?t=81139 A...

www.audiosciencereview.com

 

[Thrill Killer]

I think many of us have to go the valve/tube route, at least for a while, in our journey. My take today is to go right ahead, but choose carefully and make sure you're aware of the pitfalls, costs on occasion and performance compromises in almost all domestic-audio valve designs

Thank you. I chose the Cayin HA-3A.

 

[Jim Taylor]

It's the same reason that us, we in the hobby switch gear. We buy gear then after awhile vend to get something else. Always tweaking, always seeking. It's a part of the hobby.

It's not part of the hobby for me, but if it is for you, that's OK. My interest in this hobby is listening to the music. That's why I said ...

OTOH, if you want affected sound, be prepared to enter a swamp through which you will slog, maybe for years, with no guarantee of success.

Part and parcel of that slog is, of course, the money spent. Obviously, I'm cheap.
I wish you the best of luck!

 

[Thrill Killer]

It's not part of the hobby for me, but if it is for you, that's OK. My interest in this hobby is listening to the music. That's why I said ...



Part and parcel of that slog is, of course, the money spent. Obviously, I'm cheap.
I wish you the best of luck!

Thank you.