TA-377A Complementary Symmetrical FET Pre Amp

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I recently aquired a TA-377A Pre amp.

For those not familiar with the pre amp it consists of a regulated power supply, a line stage and a phone stage. The line stage and phono stage are complementary and symmetrical FET designs.

It sounds like it could be very good and I am presently improving the capacitors to try and make it even better.

However I would like some information if anyone can help.

1) Does anyone know of any articles or threads on this pre amp. I have searched this forum and google but did not find any.

2) the fets are listed as 2n3268 (J40) and 2n3269 (K81). I can not find any specifications for those. Does anyone know these fets?

Any help appreciated.

Don
 
Hi KaLok

I bought the pre amp second hand. However I believe it originated in HK. Although a company in the US - Mark5 - also sell the pre amp as a kit or ready assembled.

I have been playing with the pre amp some more and now it really is delivering very high quality sound so I am keen to find out more if I can. Are you able to help?

Don
 
TA 788 PRE

I recently aquired a TA-377A Pre amp.

For those not familiar with the pre amp it consists of a regulated power supply, a line stage and a phone stage. The line stage and phono stage are complementary and symmetrical FET designs.

Hi Don

In October 2012 uou posted cct of
TA788 fet preamp
You mentioned that you hawe the transistor numbers and other info of this pre.
I hav built the Pass B1 which is similar.
Recently got a TA 788 which has been messed up.
Need more info to get it live.
Please send me the info if it is not of a neusance to you.
Must do something to kill time this lockdown period.
Thank you.
John.
 

Attachments

  • Screenshot_20200428-131402.jpg
    Screenshot_20200428-131402.jpg
    351.4 KB · Views: 169
srian

Not sure I understand your comments.
I said that I would like more information on the pre amp. I also gave the numbers of the fets used in the pre amp. I have no more information but I would like more.

meanie

If you have any information it would be great if you could add it to the thread or send by email which ever is best for you. I would like more info on the pre amp.

Don
 
TA 788 PRE

Don

I have attached the cct you posted in Oct 2012. According to my imagination,
The input complementaru pairs Q1 Q3 Q5 and Q7 must be 2sk170 bl and 2sj something.
Likewise I do not know the numbers in the other Q numbers as the diagram does not mention these.
So to find currently available replacements it is impossible without these numbers.
I thought you had them when you mentioned you had part numbers.
Thats what I ment.
The numbers are missing in my pcb.

With luck meanie might have these.
 

Attachments

  • TA388.pdf
    125.8 KB · Views: 123
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.