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12AY7 circuit?

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12ay7 Circuit

hello and sorry to bother you but if you can please help me

i have absolutely no expirience on working with tubes
i have about 20 12ay7 tubes from the police I bought them from scrap all of them sealed brand new together with some other exotic tubes and i was thinking that i could make a line tone control preamplifier with them to use with my cd and power amp ....

i found fender schematic i can read that but dont know if line levels are switable to this circuit and also of course i can construct proper power sup for all these but i dont even know the numbering on the pins of the tube !!!

as i said i dont have a ny knowledge about tubes how can i tell on the schematic which pin is which and also nowere is any note about filaments ....is this taken for granded ???

please help me out

find att. of the fender schematic and if you have something that meets my specs please give me

thank you
 

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Re: 12ay7 Circuit

sakis said:
i have about 20 12ay7 tubes from the police
I won't ask! :D

Seriously though, the 12AY7 can be one of the nicest sounding Novals, so lucky you! What brand are they?

sakis said:
i found fender schematic i can read that but dont know if line levels are switable to this circuit and also of course i can construct proper power sup for all these but i dont even know the numbering on the pins of the tube !!!
This page should help you out for that.

Hopefully someone else can suggest some other circuits for you too.

Please read the "Tube Safety" thread which you can find on the first page of this forum.
 
hello sakis I am from Greece too.
I have no experience in the 12ay7 tubes but it seems to me better than the 12ax7.
Forget about your circuit posted here if you want good performance.
If you go for triodes, go for single ended topology (true class-A).
Find the datasheet here:
http://www.mif.pg.gda.pl/homepages/frank/sheets/049/1/12AY7.pdf
it has a quite good amplification factor of 40.
To ensure transparency I would use one single 12ay7 for both channels (i.e. one stage only). Then If I needed more gain I would add another identical stage in series.
Check out my page of a similar design that I have designed.
http://www.neazoi.com/page/audio/pc88/pc88.htm
more of my audio projects can be found here.
http://www.neazoi.com/page/audio
and the main site is here.
http://www.neazoi.com/

By the way what other tubes exotic have you got?
 
If you decide your not wanting them, I am always hunting for those for vintage Fender guitar amp projects.

Fresh ones are getting a bit tough to locate at a fair price. EH makes a current production version, but IMO they are a bit brittle compared to NOS GE or RCA's.

The last bunch I got from EH turned microphonic in about 20 hours of use, though this is in a fairly high gain enviroment.

Trout
 
ok guys ......

really thanks a lot .....

i will actually take a look in all these and let you know

all the tubes i have are jan and also made of motorola so i trust that they are perfect quality

trout
.... no problems i have plenty make a simple circuit for a tone control preamplifier for me ( since i have no design skills AND ALSO DONT WANT TO MESS UP IN ANYTHING TO COMPLÉCATED )
and you will find some 12ay7 in your xmas mail box ha ha ha

neazoi

thanks for your interest yet i havent checked your links but as i mentioned above i dont want anything too extreme or too complicated

after all i am a transistor person and i only doing this cause i have the tubes it may sounds perfect but i cannot construct things that will last less than 100 years ( he he he )
 
O GOD !!!!!

come on guys !!!! all these information i cannot use .......

tdsl data i ve seen before but dont know what to do with them what i am asking for is a complete schematic with voltage and pin layout

having a pdf link about the complete data of the lamp is something i cannot use !!!!!!!!!!!!!:smash:

dont know how :confused: :confused: :confused: :confused:

only thing i asked is a circuit for one input for a cd player ,tone control bass and treble and out enough to drive one amplifier with 1+ volts input

thats it !!!!!
 
Re: excuse me

sakis said:
but i said that i dont have ahinch about tubes so what i say may be not right

fender uses this tube for tone control circuit ..... and yes you are correct cd out is about 2vso any circuit with gain 1 will do the trick ......

if input is about 2v and the loos from tone control doesnt make it less than 1v in the out i am more or less ok i think

A Fender guitar amplifier is designed to have a sensitivity of probably <100mv, a far cry from a CD player...

Search here, there are plenty of circuits for 12B4 line stages

7N7
 
dear sy

in transistor world if you look at circuit for example 50w amplifier class AB and 40 volt rails some nice guys in the forum will point to you a bynch of circuits with a lot of goodies included
like pcb componet lay out various types of trs and goes on

probably the same exists for tubes ..... but since tubes talk different language somebody simply have to point me a better or more detailed schematic ...nothing really costum here ...

compaired to available transistor schematics shouldnt be that difficult ...... i think .... but also dont know ....
 
Re: dear sy

sakis said:
in transistor world if you look at circuit for example 50w amplifier class AB and 40 volt rails some nice guys in the forum will point to you a bynch of circuits with a lot of goodies included
like pcb componet lay out various types of trs and goes on

The fact that you didn't find a schematic, and that nobody pointed you to one, should come as a clue that the 12AY7 is not appropriate for your needs. 7N7 suggested the 12B4, which is a very good option. There are others, of course, but that one in particular is simple enough that an afternoon with the NEETS manual (linked above, or try Google) will be enough to understand it.

And, SY is about the nicest guy around -- your implication that his comment made him less than nice won't win you any friends.

sakis said:
probably the same exists for tubes ..... but since tubes talk different language somebody simply have to point me a better or more detailed schematic ...nothing really costum here ...

Unlike in the transistor world where stuffing a PCB constitutes DIY, Tubes are more hand's on and builds tend to be more unique. That said, you could use 12ay7's in an Aikido circuit -- here's a PCB http://glass-ware.stores.yahoo.net/newhardware.html

sakis said:
compaired to available transistor schematics shouldnt be that difficult ...... i think .... but also dont know ....

Then you should learn ...
 
i give up

just skip the all thing ....it seems that my lack of knowldge on this thing made me look like i wanted to insult somebody .....well i didnt

but in any case just skip the all thing ....i will stick to transistors and the people that work and come arround them ....

thanks for your try in any case i do respect and apriciate all the people spent a moment looking at my post

thank you and merry xma s
 
in transistor world if you look at circuit for example 50w amplifier class AB and 40 volt rails

But that's not what you're asking. You're asking for a very specific and specialized circuit using tubes that aren't very common. If you just want a tube preamp with tone controls, there's lots of circuits around, but your question is not likely to have a simple link as an answer.

My suggestion is to put the tubes in the closet for a while, hit the books, learn the basics of tube design, then pull them out and start experimenting. Or if you just want a preamp, forget about using the specific tubes you have on hand, just build a circuit that fills your requirements. The tubes themselves are a fairly minor proportion of the total cost of building a preamp.
 
diyAudio Chief Moderator
Joined 2002
Paid Member
Re: dear sy

sakis said:
in transistor world if you look at circuit for example 50w amplifier class AB and 40 volt rails some nice guys in the forum will point to you a bynch of circuits with a lot of goodies included
like pcb componet lay out various types of trs and goes on

probably the same exists for tubes ..... but since tubes talk different language somebody simply have to point me a better or more detailed schematic ...nothing really costum here ...

compaired to available transistor schematics shouldnt be that difficult ...... i think .... but also dont know ....


Fast food, here you are. Audionote, no tone controls. Too much gain. You have been warned. And please don't give grief to SY. It takes some participation and eagerness to learn and SY helps even down to novice wiring level questions.
 

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salas ....

this fast food preamp is made for me ?????

cause it has no tone control and also it seems that filament are powered with 12 v and i thing that this lamp works with 6.3 ?????



i ve been warned about too much gain ???? sorry didnt get this ??? be more specific ........

still fender uses this as a tone control preamp if iam thinking transistorwise the only thing might be needed to change is gain and/or input sensitivity

please excuse if i say something wrong and correct me if i am wrong thank you again
 
diyAudio Chief Moderator
Joined 2002
Paid Member
You can tie together pins 4&5 and apply 6.3V between them and pin 9. That will consume 300mA heating current per valve. The gain is going to be 24-25 times in practice(28dB). That schematic is a 2 stage stereo full line famous Audionote preamp, having a common cathode input stage and a cathode follower. It needs a 100k log pot on its input for volume control. Tone controls you can add from another suitable schematic for guitars or something. No hi-fi schematics with that tube sport tone controls as far as I have seen.
 
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