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6L6 / EL34 / EL84 / 6V6 frequency response curves?

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You will never get a unique solution if you only stick to power tubes.
Solution to what? Nobody asked for a solution. They asked whether power tubes had a frequency response of their own.

Yes, it doesn't for all those who don't play it and insist viewing things from HiFi perspective which is totally wrong.
The amp has its own frequency response without the guitar being plugged in. Do you know what 'frequency response' means? (I'm serious)

In the attached pictures there is the frequency response in air of the same single 10" cone driven by a current amp and a voltage amp.
Irrelevant to the thread.
 
Solution to what? Nobody asked for a solution.
Answer! You won't get a unique answer. It's all pointless from a real perspective. I told you are confused because you have little idea about how it works.

They asked whether power tubes had a frequency response of their own.
Then the thread could have been closed a long time ago! Unfortunately has very little to do with real world....

The amp has its own frequency response without the guitar being plugged in. Do you know what 'frequency response' means? (I'm serious)
Do you know the difference between HiFi and live music? I am serious. Do you use a guitar amp for music playback, usually? It is the perspective that matters. You need to know what guitar you want to use before buying an amplifier or the contrary. Not every combination works...


Irrelevant to the thread.
IPSE DIXIT!
 
Answer! You won't get a unique answer. It's all pointless from a real perspective. I told you are confused because you have little idea about how it works.
How WHAT works? Frequency response? Power tubes? Maybe I would have some idea how 'it' works if you would explain what 'it' actually is.

Do you know the difference between HiFi and live music? I am serious.
So... you don't know what 'frequency response' means, then?

You need to know what guitar you want to use before buying an amplifier or the contrary. Not every combination works...
Yes, but that has nothing to do with this thread. You said the guitar could influence, i.e. control the frequency response of the amp, which is clearly wrong.
(Your words: "the frequency response of a typical guitar amplifier is TOTALLY dominated by the guitar")
The 'frequency response' of the amp is its amplitude response, irrespective of what is plugged into it. The guitar is another part of a larger system which we're not discussing in this thread.
 
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How WHAT works? Frequency response? Power tubes? Maybe I would have some idea how 'it' works if you would explain what 'it' is you're meandering about.
I think it is quite clear. Then you can decide if you are not good enough to understand or just taking the ****!!! In former case it's like washing the donkey's head, it doesn't have any effect.

So? You said the guitar could influence or control the frequency response of the amp, which is clearly wrong.

Yes, it is wrong in your biased limited mind.
 
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I think it is quite clear.
It is not clear what you are talking about, that is why I asked you. Since you refuse to tell me, I must conclude that you don't know what you're talking about.

How does that guitar dominate the frequency response of an amplifier when it is not plugged into it? I would love to know. Magic? Telephathy?

It's not you deciding what is relevant.
It is obvious to everyone what is relevant. You were confusing the OP with falsehoods and unrelated material. I decided to correct you, to avoid others being misled also.

That's arrogance especially because you are not a musician!
Incidentally, I do play electric guitar.
 
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It is not clear what you are talking about, that is why I asked you. Since you refuse to tell me, I must conclude that you don't know what you're talking about.
No, I refuse because I really dislike your attitude. It's different. If you can't understand it's not my problem. You can also ignore it and stick to your beliefs...Think what you like, I don't care.

In the meantime I have shown you how one of my 10" cones behaves with or without feedback. You have posted nothing. All you said is hot air....


You were confusing the OP with falsehoods and unrelated material. I decided to correct you, to avoid others being misled also.
Then here again is your arrogance. Falseholds and unrelated material? I really doubt you play a guitar well enough to be called musician! Then you are basically supposing that the OP is stupid. Congratulations!
Think for yourself for once. Don't suppose what others can understand or not understand.

Incidentally, I do play electric guitar.
Then you can measure your amp in all the possible ways I have described and get answers. If you had answers (i.e. measurements) you wouldn't be asking me and would show them. Why don't you do it? I can wait...
 
I really doubt you play a guitar well enough to be called musician!
I'm not a professional musician, if that's what you mean. I'm a professional engineer. But what does that have to do with the present discussion? Being a professional engineer makes me better qualified to comment on technical phenomena than being a musician. Musician are artists, not engineers; they usually don't understand the physics of the equipment they use.

If you had answers (i.e. measurements) you wouldn't be asking me and would show them. Why don't you do it? I can wait...
Answers to what? Measurements of what? What are you trying to explain? I'm genuinely trying to help you overcome the language barrier, but you're not making it easy.

In the meantime I have shown you how one of my 10" cones behaves with or without feedback.
Yes, but you didn't say why you showed it. What point were you trying to make?
 
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Being a professional engineer makes me better qualified to comment on technical phenomena than being a musician.
Really? But you need to know how a guitar amp works and cannot mix technical things with musical definitions if you want to give a purely technical advice. See below....

Musician are artists, not engineers; they usually don't understand the physics of the equipment they use.
Musicians don't need to understand physics. They just play and listen. That's the way to make music....

I'm genuinely trying to help you overcome the language barrier, but you're not making it easy.
It's you having a problem with the language. You cannot define brighter if you don't listen to it and if you listen then you need a speaker. As you mentioned Fender amps, these are possibly among the (if not THE) brightest amps in the world regardless of the power tubes they use, EL84 or 6L6. All sorts of tone controls and their speakers make them that way not the type of power tube.

Yes, but you didn't say why you showed it. What point were you trying to make?

To show you, for example, that your funny idea about the brighter sound of pentodes a priori is total nonsense. Just considering a "non-distorting" output stage, it's the frequency response of the speaker that changes a lot with and without feedback in the AUDIO range.
 
True, some people describe different tube types in terms of what they think they hear.

Some people even claim that different tube brands sound different. Or even diffrent examples of the same type in the same brand.

Whole textbooks and many papers in learned journals have been written by electronics engineers and psychologists about why people think there are differences in things where there is in fact no difference at all. People imagining non-existent or reversed differences is a major problem in the drug industry and seriously frustrates development and optimisation of medical treatment.

There is a well known difference, easily demonstrated by instruments and known about by electronic engineeers since tetrodes were invented in the 1930's between triodes and tetrodes and pentodes. Pentodes have slightly higher distortion compared to beam tetrodes intended for audio, but the difference is so slight that in various circuits the difference is often reversed.

For tetrodes and pentodes, the sound doesn't inherently depend on the tube. it depends on teh circuit and the quality and type of output transformer.

All the types you nominated are tetrodes (6V6, 6L6) or pentodes (EL34, EL84). However these particular pentodes have higher gain than these particular tetrodes.

There is no intrinsic diffrence in the sound of an EL34/6CA7 compared to the 6L6 for example, but the EL34 has much higher control grid gain (11 mA/V vs 6 mA/V) and different screen characteristics. So, if you start with an amplifier designed for 6L6, and drop in an EL34, the amplifier may become unstable. You hear the instability as distortion. But an amplifier intended to take a EL34 won't be unstable and will sound the same - other aspects (eg transformer design) being equal.

If the amplifier is an ultralinear type there is a measurable (with instruments) difference with 6L6 and EL34 in the same amplifier due to the different screen characteristics. It is quite unlikely that anyone's ears can tell the difference. And the slight difference that is detectable on instruments can be easily reduced or eliminated by adjustment of the transformer screen tapping point.

The human ear cannot detect small changes in volume (1 dB or less) as a change in volume. But we DO hear the change - as a change in bass and clarity. Quite a number of journal articles have appeared that describe how double blind auditioning has identified a diffrence in clarity, bass, or treble, investigation by engineers shown that there was a diffrence in volume. When this was corrected, the auditioners could not detect any difference - even when differences in distortion beween amplifiers were easily detected on instruments.

Due to the peaky nature of music, all but the highest power amplifiers in audio service are routinely overdriven momentarily in any musical selection, unless reproducing vinyl or radio braodcasts, which are compressed. With CD's, even when played at moderate volume for personal listening, momentary overdroves are routine. Even with vinyl, overdrives occaisonally occur except for listening a quite levels.

The ear cannot easily detect occaisonal momentary overloads. Some people cannot detect it at all. (We can all, of course, easily detect overdrive once it occurs continuously.) However, less than perfect amplifier circuit design can result in an amplifier than does not instantly recover from an overdrive, and remains parallised for a short time after. This parallysis is easilty detectable and sounds horrible. A type of overdrive response called re-entrant clipping, once not uncommon in solid state amplifiers, also sounds bad.

Make no mistake. The behavior of audio amplifiers (both tube and solid state) under overdrive is VERY important and is a major reason why some sound a lot better than others, and why some sound different than others. Overdrive behaviour is determined by circuit design, not the tube type. Unless of course the tube is worn out or faulty.


I Don't Care.. I'm gonna call ******** on most of that... just about Every Tube Type/Different Manufacture like that, I can Tell the Damn Difference be it Clean or Clipping/Distortion.
An EL34 any of them.. sounds Nothing like actual Good 6l6s Phillips/Sylvania's etc....Beam Types sound like Beam Types...and You Guessed it Pentode's Sound like Pentode's....
And I Don't Care how Technical you want to get I know what I'm hearing. And every Manufacture Also sounds different damn near....Not My fault others can't hear/Listen for and Recognize the differences... but to Blatantly say there is no difference/they all sound identical is ignorance...
 
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So, can someone post plots of frequency responses of, say, 10K and 100K resistors? I know sound changes when you insert them to a RC filter circuit....

That means resistors must have a frequency response, right? Perhaps not.

After all, we are pretty much talking about something similar here. We can't have active tube circuits working without those tubes, yet tubes alone, without a circuit, do nothing. In the end, sound is always a result of the entire circuit.

But now that OP specifically wanted to limit discussion to tubes alone, even more, tubes amplifying clean, I think all has been said in pretty much the first pages of this thread. As is, tubes don't have a frequency response any more than plain resistors do. A circuit might and will have one, not too surprisingly it might be even largely dictated by certain properties of said tubes (or resistors) but then it's a different topic of discussion.
 
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You cannot define brighter if you don't listen to it
Yes you can... all you need is a frequency response graph that rises or is more extended in the higher frequencies (relative to another graph)...

To show you, for example, that your funny idea about the brighter sound of pentodes a priori is total nonsense. Just considering a "non-distorting" output stage, it's the frequency response of the speaker that changes a lot with and without feedback in the AUDIO range.
But nobody asked about the frequency response of speakers. You could have an amp with an enormous treble boost, then partner it with a speaker with a massive treble cut, and end up with a system with a flat frequency response. What does that prove? This thread is about power tubes and their associated circuitry, not the overall system. Not the musician, not his guitar, not the speaker, not the room he's playing in....

If it makes it easier, you can assume everyone is talking about the same musician, always with the same guitar and the same speaker, in the same room. Only the power tubes are being changed. Does that help you?
 
Yes you can... all you need is a frequency response graph that rises or is more extended in the higher frequencies (relative to another graph)...
No you can't! It's nothing to do with graphs. Besides wit was not about tone controls!!!

But nobody asked about the frequency response of speakers. You could have an amp with an enormous treble boost, then partner it with a speaker with a massive treble cut, and end up with a system with a flat frequency response. What does that prove?
What does this mean????
I have never seen or heard such a thing in guitar world. There is no standard frequency response. Period. It's pointelss....

This thread is about power tubes and their associated circuitry, not the overall system. Not the musician, not his guitar, not the speaker, not the room he's playing in....
If it makes it easier, you can assume everyone is talking about the same musician, always with the same guitar and the same speaker, in the same room. Only the power tubes are being changed.
Oh my GOD!!!! That question has already ANSWERED!!!!!! The thread has moved on but you don't get it. You are stuck with your language problems....

Does that help you?
You need help. Go and see a doctor.
 
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This is a very interesting topic.

From my own observations, listening, etc and from the books
I've read, from the books I have and playing through amps
with various tubes.

...they are all different by varying degrees.

HOWEVER

Musicians do more than just play.
A rare musician is one who listens.
An even rarer musician is one who conveys
the message or feeling in his/her soul through
the instrument.


IF IT WERE THAT EASY
Everyone would be A. Segovia
I. Perlman, M. Davis, V. Horowitz,
D. Allman, V Cliburn. G. Krupa....
 
I understand that when a musician says "brighter" he may mean 'more HF' or 'more HF distortion, but not too much more'. Some musicians may be able to distinguish between these two quite different situations; some may not; I suppose a few may even deny there is a difference or get agitated when an engineer insists they are different.

When an engineer says "brighter" he almost always means 'more HF'.

It is conceivable that there are some musicians who don't realise that tone controls work by varying the frequency response of an amplifier or preamp; they may imagine that a knob can vary 'tone'.
 
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