Topic: which tubes should i switch out first..?

[macdaddy]

looking to try some new tubes out...

which should i try first...

the preamp tubes(12ax7)..?

the output driver tubes(12at7)..?

the output tubes(el34)..?

is $80 alot for matched quad of mullard el34 tubes..? price does not include shipping...

thanks, in advance,  for any info...

[BCostigan]

I'll be asking this same question (not sure what tubes) in a few weeks........

[EScott]

I've been told that the pre amp tubes are the most important.  That's just word of mouth though...

[Nick Culbreth]

In my experience swapping out the the preamp tubes yielded the impact on the sound, so I'd experiment with ther 12AX7s first.  Afterward I'd experiment with the 12AT7s to try to finetune the preamp section's sound and then move onto the power tubes.

I'm guessing that the mullard el34s you're talking about are the current production New Sensor, Russian made Mullards and not NOS Mullards based on the price.  The cheapest price i've seen on the Russian Mullards is $78 per quad, so that price seems fair.  From what I've gathered the Russian Mullards sound OK but aren't dramatically different than the ElectoHarmonix and Sovtek EL34s which isn't suprising considering they're made in the same factory.  Some feel that they sound a bit different but I'm not  sure the difference would be worth spending twice as much for the Mullard logo.  If you do opt to get some feel free to share your thoughts on them, I've been meaning to buy a pair but I've been very busy with school and just haven't found the time to do so.

Have fun with your tube rolling. 

[ducati]

If you think $80 a quad is alot for power tubes, you 'aint seen nothin' yet 

Which you should change out first will ultimately depend upon the current amount of hours on your tubes--if your power tubes are getting old, you might get the most sonic benefit from replacing them first.  All things equal, I think preamp tubes make more of a difference, assuming equal quality tubes throughout.

I have just concluded a nice set of tests with 12AX7s:
New Production:
EH 12AX7
Ei Elite 12AX7
Groove Tube "Mullard" 12AX7M
Sovtek 5751

NOS:
Telefunken Smoothplate
Mullard Shortplate
Mullard Longplate
TungSol 12AX7

What type of sound are you looking for?  I can give general impressions, based upon my tests (although keep in mind all gear is different and tubes may well sound radically different depending upon the circuit, I think generalities are OK).

[macdaddy]

i am running a pair of EH 12AX7 now...

i am also running 4x EH el34

and 2x jan phillips 12at7

they all have roughly the same number of hours...

+t all 'round for the input.

[Nick Culbreth]

i am running a pair of EH 12AX7 now...

i am also running 4x EH el34

and 2x jan phillips 12at7

they all have roughly the same number of hours...

+t all 'round for the input.

Since you already have ElectroHarmonix EL34s I'd try either a set of Svetlana (labeled SED) or JJ EL34s instead of the New Sensor Mullards, because both are a little more musical and would be a greater contrast to what you already have.

I have just concluded a nice set of tests with 12AX7s:
New Production:
EH 12AX7
Ei Elite 12AX7
Groove Tube "Mullard" 12AX7M
Sovtek 5751

NOS:
Telefunken Smoothplate
Mullard Shortplate
Mullard Longplate
TungSol 12AX7

Feel free to share your thoughts. 

[ducati]

I'll writeup a full review after I get all the spring cleaning/yardwork done (weeks, man, weeks!)... 

How many hours do these tubes have on them?

[barren4]

Since I've not seen any discussion on this, I figure this is a foolish question but... If your preamp (in this case ys symphonies +) has the same type input tube as the output tubes (12ax7) is there any reason for the input tube to be matched to the output tubes?

[macdaddy]

How many hours do these tubes have on them?

lots. at least two years' worth.

[Nick Culbreth]

Since I've not seen any discussion on this, I figure this is a foolish question but... If your preamp (in this case ys symphonies +) has the same type input tube as the output tubes (12ax7) is there any reason for the input tube to be matched to the output tubes?

No, matching the input tube and the output tubes is not necessary.

[barren4]

Since I've not seen any discussion on this, I figure this is a foolish question but... If your preamp (in this case ys symphonies +) has the same type input tube as the output tubes (12ax7) is there any reason for the input tube to be matched to the output tubes?

No, matching the input tube and the output tubes is not necessary.

Thanks

[ducati]

How many hours do these tubes have on them?

lots. at least two years' worth.

Well, two years worth = 17520 hours which is a ton 

I go through a set of powertubes about every year.  I'm guessing 1500-2000 hours easily for a year.  Guesstimate how many hours you have on them.

The reason I am asking: if your power tubes are still good, change the pre tubes first.  If your power tubes are on the end of their lifecycle, change your power tubes first for best bang-for-the-buck.

[macdaddy]

How many hours do these tubes have on them?

lots. at least two years' worth.

Well, two years worth = 17520 hours which is a ton 

well, right - but i dont leave my tubes on 24/7

but i would say between 3100 and 4200 hours (30-40 hours a week of ON time) + whatever was on them when i bought the unit...

I go through a set of powertubes about every year. I'm guessing 1500-2000 hours easily for a year.  Guesstimate how many hours you have on them.

The reason I am asking: if your power tubes are still good, change the pre tubes first.  If your power tubes are on the end of their lifecycle, change your power tubes first for best bang-for-the-buck.

i was hoping to upgrade and get fully accostomed(sp) to new interconnects and the DAC setup (which might be further modified in late june) before getting new tubes - so i am more realistically looking at investing in some new ones in august...

but it still doesnt hurt to ask...

+t for all of the input.

[SonicSound]

Solid State Rocks .........

12AX7

[ducati]

My guess is those are getting quite worn out.  I think you'd be amazed by just switching same tube for same tube.

You run EL34's?  Want to borrow a quad to see how worn yours are?

[macdaddy]

My guess is those are getting quite worn out.  I think you'd be amazed by just switching same tube for same tube.

You run EL34's?  Want to borrow a quad to see how worn yours are?

absolutely!

[ducati]

PM me your addy and I'll send them out.

[JackoRoses]

yea yea this is a old thread, but I am looking at getting a tubed pre and
after talking with this guy, I wanted to share his comment.
"Are you aware that tubes can last 20 or 30 years?"
This was in reply to the fact his pre has original tubes in it and will be needing replaced
and I was trying to work him down off his price since he was taking offers.
Obviously he is not interested in offers at all but anyway, I thought I would share
that little comment.
I replied back "stating yes you are right, they can last 20 years or better."
"How good do they sound though and how many hours have they been ran?"
Sure a NOS tube 30 years old will sound sweet, but take that same tube and run it for 3,000 hours.
I don't think it is quite the same do any of you?

[Lil Kim Jong-Il]

Sure a NOS tube 30 years old will sound sweet, but take that same tube and run it for 3,000 hours.
I don't think it is quite the same do any of you?

You are right, it's more a matter of milage than age.

The rule I was taught when I started buying tube gear is to always expect the tubes to be worn out because people always underestimate the hours on them.  And the longer time since the tubes were purchased, the more the estimate will be low.   Since tubes often degrade rather than fail, it's possible for someone who has no sense of what a new tube sounds like to think their tubes sound fine.

[Nick Culbreth]

yea yea this is a old thread, but I am looking at getting a tubed pre and
after talking with this guy, I wanted to share his comment.
"Are you aware that tubes can last 20 or 30 years?"
This was in reply to the fact his pre has original tubes in it and will be needing replaced
and I was trying to work him down off his price since he was taking offers.
Obviously he is not interested in offers at all but anyway, I thought I would share
that little comment.
I replied back "stating yes you are right, they can last 20 years or better."
"How good do they sound though and how many hours have they been ran?"
Sure a NOS tube 30 years old will sound sweet, but take that same tube and run it for 3,000 hours.
I don't think it is quite the same do any of you?

The lifetime of tubes can vary greatly depending greatly on the type and manufacturer.  The surest way to find out how much life they have left is to get a reading on them from a calibrated tube tester, but that's probably out of the question.  Other than that I'd find out what kind of tubes he is using and do some research on audioasylum to get a ballpark on their expected lifespan and then go from there.

[macdaddy]

PM me your addy and I'll send them out.

did you ever send these, amigo..?

[JackoRoses]

yea yea this is a old thread, but I am looking at getting a tubed pre and
after talking with this guy, I wanted to share his comment.
"Are you aware that tubes can last 20 or 30 years?"
This was in reply to the fact his pre has original tubes in it and will be needing replaced
and I was trying to work him down off his price since he was taking offers.
Obviously he is not interested in offers at all but anyway, I thought I would share
that little comment.
I replied back "stating yes you are right, they can last 20 years or better."
"How good do they sound though and how many hours have they been ran?"
Sure a NOS tube 30 years old will sound sweet, but take that same tube and run it for 3,000 hours.
I don't think it is quite the same do any of you?

The lifetime of tubes can vary greatly depending greatly on the type and manufacturer.  The surest way to find out how much life they have left is to get a reading on them from a calibrated tube tester, but that's probably out of the question.  Other than that I'd find out what kind of tubes he is using and do some research on audioasylum to get a ballpark on their expected lifespan and then go from there.

They are stock tubes, he said in his description they were never replaced and will probably need replaced soon. He was the original owner of 3 years on it.
I take whatever someone says about their audio equipment with a grain of salt, even ones I know.
It is too easy for people to be dishonest about their equipment. (around here I have more faith)
Example: speakers I just bought, I asked the guy what he listened to on them, he claims christian opera and the likes. Sounds great, but there is no way of proving that is true.
The best I can hope for is that they were taken care of and he was truthful.