Too Many Tubes?


More as a thought experiment than as a description of an actual problem that may or may not exist...

Has anyone ever considred if there might be a problem with too many tubes in a given system? How many tubes is too many, and what might be some issues that could have a detrimental effect on system sound quality?

What do I mean by too many tubes?
1- too many physical tubes (by quantity). Consider an example where you have (let's say) 20 or more physical tubes distributed in your power amp, pre-amp, phono stage and DAC. Besides the obvious potential issues with heat and the cost of rolling and replacing so many tubes, what are the disadvantages (if any) of utilizing so many tubes?

2- Same question, but this time the concern is not the physical number of tubes but the variety of tube types used in a given system. Can anyone make an argument against (or for) using a large variety of tube types in a single system?

For years I used a system with a SS amp (Krell, then McCormack) and ARC tube pre and phono stage. The ARC gear used the same 6922 tubes, and it there was a well-defined (not necessarily great) sonic signature. It was also very easy to tell when a given tube was microphonic or going bad.

Lately, I have been swapping a lot of new (to me) used gear in and out, and the all-tube setups have varied from SET to integrated tube amps w/ phono to all CJ tube seperates. All good... well, mostly, but I have noticed that in the setups with many tubes and/or many tube types it is can be hard to pick out the characteristics of a single tube or tube type. I am not saying that that is good or bad - it just is what it is.

Comments?
br3098
Until recently my system required more than 100 tubes to operate and I never had any problems figuring out when something was wrong. Then again, I've used tubes for many years and know what to listen for.

Tubes have a job, just like transistors do. Depending on what you like you can't have "too many" of either.

A good example? Listen to Les Paul or Louis Armstrong where the entire recording from microphone to LP is all tubes, not much to complain about and some of those recordings are half a century old. By comparison some modern stuff is dreadful.

You also ask about variety of tubes in a system. I don't look at it that way, I choose equipment for it's performance and if the tubes chosen can be tweaked by substituting something better (like NOS), I will do so.

but I have noticed that in the setups with many tubes and/or many tube types it is can be hard to pick out the characteristics of a single tube or tube type. I am not saying that that is good or bad - it just is what it is.

I can't do this in an unknown system, but I can hear and remember what each tube does in my system, from input on my amps to rectifiers in my phono. It does take a lot of time and listening but after awhile I can make a cable, footer or phono cartridge change and discuss with others in my group what might be changed (tubes and otherwise) to make it more right.
Tu-be or not tu-be. that is the question.
For me, the biggest disadvantage to using too many tubes is that switching tubes are an easy route to feed into the need to tweek and try to improve and not be satisfied with the status quo. I'm pretty busy and researching- purchasing tubes can get out of hand and they sometimes get in the way of actually enjoying music.
"Tu-be or not tu-be. that is the question."
I wouldn't shake a spear at that statement.

As to the OP's question: It's a "forest or tree" situation.
Could the tees be in the way?
Tubes, triodes in particular, are still the most linear form of amplification known. So using tubes generally allows one to have less stages of gain and that leads to simpler circuitry. IMO its a lot easier to have too many transistors :)
"I'm pretty busy and researching- purchasing tubes can get out of hand and they sometimes get in the way of actually enjoying music."

Boy! Can I ever feel where you're coming from. The only catch is, when you find that special tube, as Andy from Vintage Tube Services helped me do with a pair of NOS RCAs, and it transforms your system, all the effort becomes so very worthwhile.
The problem is with rolling equipment through your system and not having a system together long enough to really learn it. I think about systems I knew intimately. I could hear a change in the system by breaking a connection be it an interconnect or speaker cable. In those systems a tube going bad was huge. When our system isn't settled in it becomes a love hate relationship with tubes and we wish for fewer tubes or even go solid state for a while as we try to convince ourselves we like the sound. How many times have you heard a reviewer say, this is the most tube-like solid state amp yet?
Old Armstrong stuff sound fantastic in my digital rig. Only three tubes in the signal path for digital in my system (the ARC sp16 pre-amp). There are 3 more (12AX7 I believe) tubes in the phono stage of the ARC pre-amp and that works quite well also.

I have a tube DAC I moved from my main system into my other system which is all SS otherwise.

I listen to everything from old jazz to classical to modern rock/pop and even hip-hop, so neutral performance for all genres is a big requirement for me.
SETS are supposed to sound better than push-pull because of fewer tubes plus triods are just great too (as posted above)if you can live with no power. Also, most tube amps use SS rectification and only a few still use tube rectifaction, which is supposed to sound better and result in longer tube life in the rest of the amp. SS or Tube, the fewer parts, the better. This is not really my opin, just what I understand is being said by everyone. Straight wire with gain!
Sure you can have too many tubes. If you have 100 tubes in your system, and they last 5 years on average, then 20 of them will need to be replaced every year - or one every two weeks. It could get pretty annoying trying to find the bad tube every other week. On the other hand, if you're up for that, then maybe you can't have too many tubes :)
I love the tube sound but problem for me is, I find an absolutely killer tube for my pre (Pope Holland 6SN7's) and know that in a few years I will never be able to dublicate the sound I'm hearing from these NOS, 1948 tubes. BUT!! I sure enjoy it while I have them.
I had many tubes once used to listen to my system in my underwear.Now i only have tubes in phono section listen in my shorts now.
If you like them and you have a tube tester when needed, maybe not.
Only if your music has too many notes!
Sounds like you are paying to much attention to your tubes and not enough to the music. If you are just going to continue to analyze and compare the sound characteristics of each tube over and over, you can't be enjoying the music and you are going to toast your brain to the point where you find it difficult to listen to music without analyzing the sound of your gear.
I've owned lots of tubed and non tubed gear over the years,but I've always been able to distinguish what output tubes were used.

Most el 34 amps sound similar, the OTL AtmaSphere sounded different, and so did the 300B and EL 84 amps all have a unique sound.

There is a problem somewhere in the chain if you can't hear any differences.
You have a lack of resolving power and somewhere there is a bottlekneck.

I don't believe it's the number of tubes that are used in a system as much as it is about how they are employed and what they are paired up with that is the problem.

My system has tubes in the cd player, tubes in the pre/phono stage and tubes in the power amp, yet I can distinguish between good recordings and those that aren't as good.

In other words the number of tubes in the loop has no bearing on the resolution of the system.
All music doesn't sound the same,you hear it warts and all.

Which is how I think a system tube or solid state, should sound like.
It's funny how many audio people are able to accept the benefits of tube rolling and its effect on sound for better or for worse but cannot digest other approaches to customizing the sound, like digital signal processing, tone controls, etc.

The results always speak for themselves and there are so many ways to tweak to get what you want.

So, it's just funny....
tube rolling & DSP are fundamentally different in that tubes may hv additive or subtractive characteristics in specific freq ranges, but they do not introduce addt'l layers of circuitry, s/ware algorithm, &/or other forms of complexity across the (entire) incoming signal.
"tube rolling & DSP are fundamentally different in that tubes may hv additive or subtractive characteristics in specific freq ranges, but they do not introduce addt'l layers of circuitry, s/ware algorithm, &/or other forms of complexity across the (entire) incoming signal."

The signal traverses the tube the same as it would a circuit.

They both affect/change the sound/signal as a result.

Plus circuits are the basic building blocks of electronics. Hard to live without them.

What makes one categorically good and the other categorically bad?

Doesn't make sense.

That's why its funny.

Darn stereos and circuits, always mucking with the sound!
I wouldn't lump DSP and tubes together as the same thing.
They aren't.

When someone uses tubes to tame some brightness, they may as well use DSP or experiment with different power cords or get a pre amp with tone controls.

Tube pre amps and amps have certain euphonic characteristics that their solid state cousins do not.
And solid state gear has it's own colourations.

What you prefer is the type of amplification that sounds right to your ears when used in your system.I can control the sound of my system, with tube or solid state amps, but they won't alter the sound of the room.There is a difference.And that should make sense.

I use a low wattage SET amp running tube rectification and 2 EL 84 output tubes.

I 've owned OTL tube amps, PP tube amps, EL 34 and 300B SET tube amps and several solid state amps from class A, AB, and D.

None of the amps made my system sound the same.
But they can't alter the "sound" of the room the amps are in.They only alter the sound of the gear as heard in that imperfect room.
Correct the room, and differences in amps becomes even more evident.
This is where a DSP unit comes into play.
Or room tuning devices.


If you have a bad sounding room, with no room treatment, poor speaker placement, it doesn't matter what type of amp you use,it won't eliminate the room problems.But a DSP used with any of the amp types above can change the way the amp and gear interact with the room,and transform the room electronically from bad to good.

Having said that,every link in the chain has a sonic signature, irregardless of the circuit or configuration. Everything influences the sound we hear coming out of our system, from the power from the panel, thru the wires and circuits and fuses and crossover and drivers etc.

We either accept the sound as it is or we tinker with it, and when that doesn't please us we try other gear or quit the hobby and become just another disgruntled former audiophile with an axe to grind.

Time has marched on, tube and solid state gear made today has less colourations than the gear made 40 years ago.

What I find sad, not funny, is that this doesn't make sense to some folks still in the hobby today.