#1
I was wanting to put this into v1 on my amp to cut a bit of gain and fizzyness, but on some reviews it recommended against putting it into high gain preamps because of potential microphonics. I'm wondering if this would be a considerable issue? Its an electro harmonix btw, just had it spare from an older amp
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#2
why dont you just try it out if you have it on hand? (Sorry i dont have an answer on that specific tube for ya)

On a side note alot of folks recomend the tungsol 12ax7 in V1...
#3
I will if I don't get a clear answer, but I would rather know going in to it if it is even a concern. It's just a long plate version of a regular eh 12at7, but I'm not knowledgeable about the differences caused by the plate extension. I normally run all jj's in the preamp, this is just a wimsy thing to see if i can kill some fizz, though I have a feeling 5751s would better suit this job
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#4
EHX are pretty meh but it will certainly give you an idea of how it will affect the gain structure. If it gets you in the ballpark start looking for a nice NOS 12AT7 on Ebay. 12AT7's sell for a lot less than 12AX7's. You may even pick up something really nice like an Amperex for a decent price.
Plug it in and try it, it can't hurt anything.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#5
Quote by Cathbard
EHX are pretty meh but it will certainly give you an idea of how it will affect the gain structure. If it gets you in the ballpark start looking for a nice NOS 12AT7 on Ebay. 12AT7's sell for a lot less than 12AX7's. You may even pick up something really nice like an Amperex for a decent price.
Plug it in and try it, it can't hurt anything.


Yeah if I like it I'm going to find me an NOS for sure, at least for that one spot. So does longer plate=more microphonic, or is it just this tube, or have I nothing to worry about?
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#6
doesn't a 12at7 have a load less gain than a 12ax7? maybe try a 5751 first?

I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#7
Quote by Dave_Mc
doesn't a 12at7 have a load less gain than a 12ax7? maybe try a 5751 first?



I would, its just this is what I have in my possession, as in, I'm impatient and want to try it now Also, I think the 5751 has about 70% of a standard ax7s gain, the at7 has about 60. so it is a difference, but i feel like it will still give me a fair idea of if i like what I hear or not.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#8
oh right, sure. i thought you were asking what to buy.

yeah, if you have one, whack it in there and see (assuming cath is right that it's safe, and he normally is).

i also think i got the at7 confused with the au7 Sorry. the 12au7 has a load less gain.
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#9
Quote by Dave_Mc
oh right, sure. i thought you were asking what to buy.

yeah, if you have one, whack it in there and see (assuming cath is right that it's safe, and he normally is).

i also think i got the at7 confused with the au7 Sorry. the 12au7 has a load less gain.


Yeah, I get em mixed too, I just happened to roll by the everything tubes thread earlier, so I have it all fresh in my head. The only thing I am worried about is this tube was designed with driving a reverb in mind, so I'm worried that that will prevent me from getting an accurate idea of the effect I am going for.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#10
Here are the gain figures:
12AX7 - 100
5751 - 70
12AT7 - 60
12AY7 - 45
12AU7 - 19

Now be aware, 12AU7's won't always work in an amp due to excessive plate voltages. They are a low voltage device really but will often work fine in a guitar amp - but not always, they aren't a direct replacement like the others.

Long plate tubes do tend to be more microphonic but not always. There are more factors than just plate length - strength of vacuum being a biggy, probabaly the biggest. A long plate hard vacuum will be less microphonic than a short plate soft vacuum tube generally speaking.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#11
Thanks cath, I knew most the stuff about the varying gains, but I had forgotten about the the ay7. Somehow i always do. The stuff about the plates is good info, ill try it out when i get everyone out of the house for a bit.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#12
yeah i got teh t and the u mixed up
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#13
Didnt know if you guys would be interested or not, I just did the switcharoo, played for a quick 20 minutes. Man, that fizz was gone! Sounds a whole lot better. Noise wasn't too much of an issue, it was still pretty quiet, even at volume 4 and with my my tele. I will be picking up either a 5751 or 12at7 for sure.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#14
It's always nice to hear how advice panned out. Often one hands out advice and only hears back if it all goes horribly wrong. Normally that means you hear nothing. Feedback is good.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#15
I understand. I'm just glad that I have somewhere to go with all my questions. If I went into a major retail store with this stuff I would be wasting my oxygen, and I would probably fizzle their brain out as well. again, Thanks Cath
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#16
Most retail stores wouldn't know a 12AT7 from a labrador.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#18
You stuck the AT7 into a 6505+? Interesting, that's a combination I never would've thought about being a super high gain head and all. Have you tried rolling back the gain to dump some of the fizzyness?

I run a JG5751 in V1 on my JCA100, I think it brings out the character of the amp moreso than the 12ax7's I've ran through it. This is a post from the moderator Roc about the at7 and 5751, I agree 100% regarding the tone of the 5751.
Quote by Roc8995
(The 5751) is billed as 70% of the gain but it really doesn't sound like it. There's a much bigger difference to me between a 12AT7 and a 5751 than a 12AX7 and a 5751, and AT7s are supposedly around 60% of the gain of a 12AX7. I won't pretend to be able to hear percents of gain, but to me a 5751 is a more civilized sounding 12AX7, whereas a 12AT7 will change the headroom and feel of an amp a bit.


And then this about the tone of the 5751
Quote by Roc8995
You'll probably notice a little less shrillness in the highs, and overall a slightly rounder tone. Best way to know for sure is to use it, though.
Endorsed by Dean Guitars 07-10
2003 Gibson Flying V w/ Moon Inlay
2006 Fender All-American Partscaster
SVK ELP-C500 Custom

1964 Fender Vibro Champ
1989 Peavey VTM60

[thread="1166208"]Gibsons Historic Designs[/thread]
#19
I've been told that the 12AT7 was never designed to be an audio tube...

They make great PI tubes.

Note: Using a 12AT7 will work for decreasing the gain, but the 12AT7 has a different set of plate family curves, which produce a slightly more bassy output.
#20
Quote by BurstBucker Pro
I've been told that the 12AT7 was never designed to be an audio tube...

They make great PI tubes.

Note: Using a 12AT7 will work for decreasing the gain, but the 12AT7 has a different set of plate family curves, which produce a slightly more bassy output.


I have heard that as well, and the bit about the bass. To flux'd, I will probably end up buying a few 5751s just to have on hand, and I will try one out in v1, but I'm fairly pleased with the overall effect of the AT7. I need a bit longer to really examine the sound with all my different guitars, I only ran through it with my tele and 7 string last night, I still need to check it out the the gibby and the ltds.
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#21
Lots of tubes that were originally designed for other purposes ended up being used for different things. Iirc the output tubes on a HT5 were originally made for the deflection circuit in cathode ray oscilloscopes. If they work they work. Hell, the micoprocessor wasn't originally designed to be a computer and the op-amp was designed to be used in analogue computers. Neither are used for the application they were designed for any more. They are two of the most ubiquitous devices on the planet, neither are used for what they were initially designed for.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
Last edited by Cathbard at Feb 17, 2012,
#22
Quote by Cathbard
Here are the gain figures:
12AX7 - 100
5751 - 70
12AT7 - 60
12AY7 - 45
12AU7 - 19

Now be aware, 12AU7's won't always work in an amp due to excessive plate voltages. They are a low voltage device really but will often work fine in a guitar amp - but not always, they aren't a direct replacement like the others.

Long plate tubes do tend to be more microphonic but not always. There are more factors than just plate length - strength of vacuum being a biggy, probabaly the biggest. A long plate hard vacuum will be less microphonic than a short plate soft vacuum tube generally speaking.


I have a 12AU7 in V6 of my 6534+ and havent had any problems at all. Bu its just there to help the cleans, doesnt do anything for leads.

May not work in all situations but worked in mine
#23
Quote by Seanthesheep
I have a 12AU7 in V6 of my 6534+ and havent had any problems at all. Bu its just there to help the cleans, doesnt do anything for leads.

May not work in all situations but worked in mine

I'll try to file that away in my memory.
"12AU7's don't die in 5150/6505's" Cntrl S

Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#24
Quote by Cathbard
They are two of the most ubiquitous devices on the planet, neither are used for what they were initially designed for.


yeah

a marshall mg was designed to attract wasps for exterminators
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#25
Yeah, I mean it could be said that no tube was originally designed for audio anyway. I mean, all the military tubes we cram in our amp? I hardly think that the russians were planning on taking over the world through the lush tone of their guitar amplifiers

^Exactly, and look how great of a paperweight it is!
I'm just a kickin' and a gougin' in the mud and the blood and the beer.
#26
Quote by dementiacaptain

^Exactly, and look how great of a paperweight it is!



I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#27
Nice thread! I feel like I'm learnin stuff... And things... And words and such... Haha!

For real though, this might help with my tube quest! Thanks!
ΦΚΣ


Life is short. PLAY LOUD!