# Looking for 12AY7



## BGood (Feb 20, 2015)

I'm looking for one or two 12AY7 to smooth out my TraynorYCV20's gain.
Any of you have some you part with ?


----------



## Latole (Aug 11, 2020)

Bonjour Jean, tu ne peux en commander ?
You can't order some ?

In Canada :
Parts connexions : 


Search Results for: 12ay7












Electro-Harmonix - 12AY7 Preamp Tube - Single


Electro-Harmonix - 12AY7 Preamp Tube - Single




www.long-mcquade.com













JJ Electronic 12AY7 Preamplifying Tube - Single | Cosmo Music


JJ Electronic 12AY7 Preamplifying Tube, Single Vacuum Tube, R.F. Double Triode, JJ Electronic Model T-12AY7-JJ.12AY7 is a medium gain pre-amplifying double triode.




cosmomusic.ca


----------



## BGood (Feb 20, 2015)

Latole said:


> Bonjour Jean, tu ne peux en commander ?


Oui je sais, mais j'essaie toujours de réutiliser/recycler avant d'acheter du neuf. Souvent ces trucs traînent au fond d'un tiroir et finissent à la poubelle. J'essaie d'aider ma planète


----------



## Verne (Dec 29, 2018)

I thought I had at least one 12AY7, but only a 12AT7. ECC81, and 12AX7. Sorry, can't help out. But if in the end you go 12AT7, contact me. Not matching granted, but also not power tubes.


----------



## Frenchy99 (Oct 15, 2016)

Désolé, aucune 12AY7 dans les fonds de mes tirroirs. Bizarre... pas une lampe que j utilise tres souvent faut croire...


----------



## Latole (Aug 11, 2020)

J'en ai quelques unes dont je ne peux me défaire comme je répare des amplis.

Bonne chance. 

Ps : Pour la planète, il est trop tard.


----------



## DaddyDog (Apr 21, 2017)

I guess I need a translate button, LOL.

The Tube Store in Ontario is the go-to place for tubes: www.thetubestore.com - Your online source for audio vacuum tubes.

Shipping can be expensive but it arrives very quickly (outside of a Christmas pandemic). I wish The Tube Store would sell a variety pack of preamp tubes at a discount. I'm always trying different tubes.


----------



## Latole (Aug 11, 2020)

He wants to recover an unused tube, to help save the planet

I often use Google translation;






Google Traduction


Le service sans frais de Google traduit instantanément des mots, des expressions et des pages Web entre le français et plus de 100 autres langues.




translate.google.ca


----------



## Verne (Dec 29, 2018)

My translator is getting worn out. but at least it's accurate in it's translations. Unlike some that are just as garbled as the original text. HAHAHA.


----------



## Frenchy99 (Oct 15, 2016)

Latole said:


> I often use Google translation;


In my younger years, I use to pick up English chicks to translate things for pillow talk...


----------



## BGood (Feb 20, 2015)

Sorry guys. Do we have to post bilingual here ? Dunno ...

Looking to recycle / re-use one or two 12AY7. I know I can buy new, but if I can spare one from going to the dump ...


----------



## BGood (Feb 20, 2015)

BGood said:


> Sorry guys. Do we have to post bilingual here ? Dunno ...
> 
> Looking to recycle / re-use one or two 12AY7. I know I can buy new, but if I can spare one from going to the dump ...


I want to try that one in my Traynor YCV20WR to maybe smooth out the gain a bit.


----------



## Lincoln (Jun 2, 2008)

I looked through my old tubes, and struck out. All I have are 12AU7 and 12AV7


----------



## nonreverb (Sep 19, 2006)

BGood said:


> Sorry guys. Do we have to post bilingual here ? Dunno ...
> 
> Looking to recycle / re-use one or two 12AY7. I know I can buy new, but if I can spare one from going to the dump ...


I have NOS ones....I'd have to check and see if I have any pulls.


----------



## BGood (Feb 20, 2015)

Lincoln said:


> I looked through my old tubes, and struck out. All I have are 12AU7 and 12AV7


The 12AU7 is the tamest one isn't it. I could try that one. Do you want to part with it ?


----------



## Verne (Dec 29, 2018)

BGood said:


> The 12AU7 is the tamest one isn't it. I could try that one. Do you want to part with it ?


Yes. The 12AU7 is often suggested for the Fender HRD so the volume knob is more useable past 1. It is a noticeable volume difference. It may bring your gain down considerably. I had a YCV40, but never tried anything less than stock 12AX7.


----------



## BGood (Feb 20, 2015)

This what I have as a reference, is it right by you ?

Gain Factor
12AX7=100
5751=70
12AT7=60
12AY7=45
12AU7=19

I guess 12AT7, 12AY7 or 12AU7 would make a noticeable change.


----------



## Verne (Dec 29, 2018)

This is the chart I have been following regarding preamp tubes with NA classifications.


----------



## BGood (Feb 20, 2015)

Verne said:


> Yes. The 12AU7 is often suggested for the Fender HRD so the volume knob is more useable past 1. It is a noticeable volume difference. It may bring your gain down considerably. I had a YCV40, but never tried anything less than stock 12AX7.


Volume AND gain reduction ? Will it proportianally decrease volume and gain ?


----------



## Verne (Dec 29, 2018)

That I can't answer for sure. 2 ways to find out though. Somebody will answer that, or once you get the tube, you'll find out. Sorry.


----------



## Paul Running (Apr 12, 2020)

You might want to check the bias voltage on those tube subs and double check the plate load impedance; you could be offsetting the bias into non-linear territory.


----------



## Paul Running (Apr 12, 2020)

In other words double check your datasheets.


----------



## Lincoln (Jun 2, 2008)

BGood said:


> The 12AU7 is the tamest one isn't it. I could try that one. Do you want to part with it ?


I certainly can send you a couple. PM me an address


----------



## DavidP (Mar 7, 2006)

I was planning to cull my stock of NOS (sorry no ANOS/used) 12AY7/6072 next year as I now only use them in my 5E3. PM me if interested...


----------



## BGood (Feb 20, 2015)

Paul Running said:


> You might want to check the bias voltage on those tube subs and double check the plate load impedance; you could be offsetting the bias into non-linear territory.


Thanks, but I think biais is self adjusting on this amp.


----------



## dtsaudio (Apr 15, 2009)

BGood said:


> Volume AND gain reduction ? Will it proportianally decrease volume and gain ?


Volume and gain are the same in this context.
If the 12AU7 works it will substantially reduce gain. The problem is that it is so far out of spec compared to a 12AX7 that the results may be unsatisfactory. On the other hand it may work. Nothing to lose by trying.


----------



## jb welder (Sep 14, 2010)

BGood said:


> Thanks, but I think biais is self adjusting on this amp.


To a certain extent only for the same tube type. They will all work, but they will be biased in different portions of their curve like @Paul Running l mentioned.
Part of why people like the 'wrong' tube in a spot may even be because of this, rather than just the gain difference.


----------



## Frenchy99 (Oct 15, 2016)

jb welder said:


> Part of why people like the 'wrong' tube in a spot


Just like the wrong women is always a temptation !


----------



## nonreverb (Sep 19, 2006)

If you REALLY want to go out on a limb....try a 12DW7 aka 7247. One half is a 12AU7 the other half is 12AX7.
In your amp, the 12AU7 side would be the primary input gain stage, the 12AX7 would drive the tone stack.


----------



## cboutilier (Jan 12, 2016)

Frenchy99 said:


> Just like the wrong women is always a temptation !


I like you more, and more, every day.


----------



## DavidP (Mar 7, 2006)

nonreverb said:


> If you REALLY want to go out on a limb....try a 12DW7 aka 7247. One half is a 12AU7 the other half is 12AX7.
> In your amp, the 12AU7 side would be the primary input gain stage, the 12AX7 would drive the tone stack.


FWIW, the Swart AST uses a transformerless cap-coupled reverb with a 12DW7 -- AU7 side drives the tank, AX7 side is recovery. Don't know who else specs these in a circuit...


----------



## nonreverb (Sep 19, 2006)

DavidP said:


> FWIW, the Swart AST uses a transformerless cap-coupled reverb with a 12DW7 -- AU7 side drives the tank, AX7 side is recovery. Don't know who else specs these in a circuit...


They can be found in various Ampegs and Hammond L100's.


----------



## cboutilier (Jan 12, 2016)

DavidP said:


> FWIW, the Swart AST uses a transformerless cap-coupled reverb with a 12DW7 -- AU7 side drives the tank, AX7 side is recovery. Don't know who else specs these in a circuit...





nonreverb said:


> They can be found in various Ampegs and Hammond L100's.


I have an amp that achieves similar purposes by using a couple 6A*6 series tubes alongside the 12a*7 series.


----------



## BGood (Feb 20, 2015)

You guys are slowly loosing me in tube lingo  Aren't preamp tubes not needed to be biased ?


----------



## Dorian2 (Jun 9, 2015)

Don't have any to spare, but I prefer the 12AY7 (EHX). They're plenty clean. Work well with pedalboard and high gain bridge humbucker. Less gain made for a little less volume. Just had to twist a knob or 2. Good luck in your search.


----------



## jb welder (Sep 14, 2010)

nonreverb said:


> If you REALLY want to go out on a limb....try a 12DW7 aka 7247. One half is a 12AU7 the other half is 12AX7.
> In your amp, the 12AU7 side would be the primary input gain stage, the 12AX7 would drive the tone stack.


There's a reverse version of that as well, the ECC823. Let's you try the other way without re-wiring the socket.


----------



## nonreverb (Sep 19, 2006)

jb welder said:


> There's a reverse version of that as well, the ECC823. Let's you try the other way without re-wiring the socket.


Not available in Canada unfortunately...


----------



## jb welder (Sep 14, 2010)

nonreverb said:


> Not available in Canada unfortunately...


I'm not sure what you mean, are they not allowed in? Or just the very small number of tube suppliers in Canada don't carry them?


----------



## nonreverb (Sep 19, 2006)

jb welder said:


> I'm not sure what you mean, are they not allowed in? Or just the very small number of tube suppliers in Canada don't carry them?


Well, the Tube Store doesn't.....probably not enough interest in them to justify stocking them.
I've inquired a couple of times over the years.


----------



## nonreverb (Sep 19, 2006)

jb welder said:


> I'm not sure what you mean, are they not allowed in? Or just the very small number of tube suppliers in Canada don't carry them?


There are other new tube suppliers in Canada apart from typical music store fare?


----------



## jb welder (Sep 14, 2010)

BGood said:


> You guys are slowly loosing me in tube lingo  Aren't preamp tubes not needed to be biased ?


Preamp tubes are 'self-biased' because they are cathode biased (some power tubes are also cathode biased and considered 'self-biasing').
The choice of components in the circuit mean the circuit will adjust for small variations for tubes _of the same type_. Other tube types may work there, but they will not be biased to their optimum. 
If I am designing an input stage using a 12AX7, I go to the RCA tube manual and look up that type of circuit. Then I enter in the voltages I am using and it tells me what value resistors to use. If I look up the same circuit but want to use a 12AY7, it will tell me to use different value resistors. The first example is self-biased when using 12AX7's.

Sorry about all this nit-picking but it's important to know that when we try different 12A*7 types in the same spot, we are not really comparing apples to apples, unless we make adjustments to the circuit.
But yes, you are correct, pre-amp tubes do not need to be biased by the user. The circuit biases them. 




nonreverb said:


> There are other new tube suppliers in Canada apart from typical music store fare?


Nope, just the one you mentioned *. I just wanted to make sure of what you meant. My local music store gets their tubes from CE wholesale in US, so I would just get them that way.

*I did see Lee's electronic in Vancouver has a fair bit in tubes, so I guess they would qualify as a 'tube supplier'. Not sure if they are new or not.


----------



## BGood (Feb 20, 2015)

jb welder said:


> But yes, you are correct, pre-amp tubes do not need to be biased by the user. The circuit biases them.


Still lost me ... so ... I'm OK with 12AY7 or 12AU7 replacing one 12AX7 without burning down the house ?


----------



## nonreverb (Sep 19, 2006)

BGood said:


> Still lost me ... so ... I'm OK with 12AY7 or 12AU7 replacing one 12AX7 without burning down the house ?


Yes, the issue they're describing is that the bias points for different 12A*7 tubes varies depending on the tube type. That said, the bias variation between them is not so far out as to cause serious operational problems rather they may not be optimally biased based on their operating spec.


----------



## nonreverb (Sep 19, 2006)

jb welder said:


> I'm not sure what you mean, are they not allowed in? Or just the very small number of tube suppliers in Canada don't carry them?


lol...banning a tube type? Sounds like a half baked government regulation.


----------



## BGood (Feb 20, 2015)

WHOA ! What a difference !

Thank you all for your advice. Special thanks to Lincoln who sent me three different 12A*7 tubes. The 12AU7 did the trick. Gain is now much tamer, less fuzzy, more organic (if there's such a thing), creamier.

Several times in the six months I owned it, I almost got rid of it, even put it up on Kijiji for a few hours before pulling the ad. I really wanted to like this beautiful little combo, I now do.


----------



## BGood (Feb 20, 2015)

29 days later ... I liked the YCV20 better with that 12AU7, but just not enough to refuse a trade with an Egnater Rebel 30 head. I guess I'm not an EL84 type, more of a 6V6. 

I put the original tube back in and tomorrow is new amp day.


----------



## Paul Running (Apr 12, 2020)

BGood said:


> 29 days later ... I liked the YCV20 better with that 12AU7, but just not enough to refuse a trade with an Egnater Rebel 30 head. I guess I'm not an EL84 type, more of a 6V6.


Or maybe more of an Egnater Rebel 30 type than a YCV20. Those same EL84s will sound different in an Egnater Rebel...the tube is the constant.


----------



## BGood (Feb 20, 2015)

Paul Running said:


> Or maybe more of an Egnater Rebel 30 type than a YCV20. Those same EL84s will sound different in an Egnater Rebel...the tube is the constant.


But the Rebel also has a set of 6V6, blendable with the EL84 pair. That's a feature I look forward to play with.


----------



## Paul Running (Apr 12, 2020)

BGood said:


> But the Rebel also has a set of 6V6, blendable with the EL84 pair. That's a feature I look forward to play with.


Yes, I was looking at the schematic for the Rebel...it is an interesting circuit.


----------



## loudtubeamps (Feb 2, 2012)

nonreverb said:


> If you REALLY want to go out on a limb....try a 12DW7 aka 7247. One half is a 12AU7 the other half is 12AX7.
> In your amp, the 12AU7 side would be the primary input gain stage, the 12AX7 would drive the tone stack.


Smarty Pants 🧐💡


----------



## Paul Running (Apr 12, 2020)

BGood said:


> But the Rebel also has a set of 6V6, blendable with the EL84 pair. That's a feature I look forward to play with.


Yes, if you take a look at the schematic of the output section...the top two tubes (V2 and V3) are EL84s and the bottom two tubes are the 6V6s. One of each is pushed on one half of the primary winding of the OPTFM and the remaining two, are pulling on other half winding...they mix at the OPTFM...that is my favourite section to mix signals...the last mixing-node to the output.
It would be interesting to scope the output of that amp...checking the phase-distortion, like how well balanced the output looks.


----------



## BGood (Feb 20, 2015)

Paul Running said:


> Yes, if you take a look at the schematic of the output section...


Can't, I go crosseyed !


----------



## Paul Running (Apr 12, 2020)

BGood said:


> Can't, I go crosseyed !


Yeah, sorry about the print quality...it did look genuine though.


----------



## jb welder (Sep 14, 2010)

BGood said:


> Can't, I go crosseyed !





Paul Running said:


> Yeah, sorry about the print quality...it did look genuine though.


Here's a clearer copy. Funny way to draw it. So the 2 upper tubes (EL84) are a push-pull pair and the 2 lower tubes (6V6) are a push-pull pair.
V2 & V4 connect to top of OT primary, and V3 & V5 connect to bottom.

There is a 'blend' control, which gives full EL84 at one end of pot, and full 6V6 at other end.


----------



## BGood (Feb 20, 2015)

LOL ... it wasn't the clarity of the image that got me crosseyed, it's the fact that I can't to save my life read an amp schematic.


----------



## Paul Running (Apr 12, 2020)

Yeah, I was wondering about the variable power control:

_*"The scalable WATTS control on each channel of the REBEL-30 MARK II varies from 1W to 30W, so you can dial in rich, responsive tube tone at any volume level. Vary the wattage easily go from the studio to the stage."*_








I do not see any attenuation control after the output TFM, on the schematic so, the power is not being partially absorbed, at the output. So, how are they controlling the output power?


----------



## nonreverb (Sep 19, 2006)

Paul Running said:


> Yeah, I was wondering about the variable power control:
> 
> _*"The scalable WATTS control on each channel of the REBEL-30 MARK II varies from 1W to 30W, so you can dial in rich, responsive tube tone at any volume level. Vary the wattage easily go from the studio to the stage."*_
> 
> ...


Perhaps similar to the London Power scaling circuit?


----------



## BGood (Feb 20, 2015)

Paul Running said:


> Yeah, I was wondering about the variable power control:
> 
> _*"The scalable WATTS control on each channel of the REBEL-30 MARK II varies from 1W to 30W, so you can dial in rich, responsive tube tone at any volume level. Vary the wattage easily go from the studio to the stage."*_
> 
> ...


Those control aren't doing much. You have to really pay attention to find a difference between 1W and 30W settings and that difference is not counted in decibels. All I find it does is get the signal kind of weaker, thinner, less dynamic. That's about it.

I've read someone complaining about it on his new amp, he returned it and it was replaced with one that showed a real difference. Go figure ...


----------



## Paul Running (Apr 12, 2020)

Maybe jb can shed some light on it?


----------



## jb welder (Sep 14, 2010)

Paul Running said:


> Yeah, I was wondering about the variable power control:
> ...
> I do not see any attenuation control after the output TFM, on the schematic so, the power is not being partially absorbed, at the output. So, how are they controlling the output power?





nonreverb said:


> Perhaps similar to the London Power scaling circuit?


Full schematic attached.
It appears to be power scaling for the B+ of the PI tube only.

There seems to be a little game going on now where they limit output from the PI stage, then call out the output levels that can be achieved due to the limited drive.
Here they use power scaled PI, Yorkville does a thing with a stepped attenuator acting as a Post PI Master Volume (YBA1Mod1, etc.).


----------



## Paul Running (Apr 12, 2020)

Okay, most of the schematics that I have seen, power-scale the plates and screens of only the output tubes.










"Those control aren't doing much. You have to really pay attention to find a difference between 1W and 30W settings and that difference is not counted in decibels. All I find it does is get the signal kind of weaker, thinner, less dynamic. That's about it."
 
I'd be interested in hearing how guitarists compare pre and post output attentuation...how many prefer a power-soaked speaker to a power-scaled PI or a power-scaled output tube setup.


----------



## nonreverb (Sep 19, 2006)

Paul Running said:


> Okay, most of the schematics that I have seen, power-scale the plates and screens of only the output tubes.
> 
> View attachment 348799
> 
> ...


I've installed power scaling circuits from London power a couple of times. They modulate the B+ voltage to the plates/screens. They do make a difference although the jury's out if they're superior to an output load attenuator. The feedback was positive from my customers although they had made the decision to have them installed.


----------

