Dual La2a - [silent:arts] version

[bernbrue]

Hi,
here is an Excel Partlist and the pcb component placement as pdf. I mailed DRIP, the price for a T4B remake is 90 USD. Will ask him for a price reduction in case we order more than ten.

http://www.twin-x.com/groupdiy/images/thumb_xls.jpg
http://www.twin-x.com/groupdiy/albums/u ... nlayou.pdf

regards
Bernd

[[silent:arts]]

this link for the parts list will work better:
http://www.twin-x.com/groupdiy/albums/u ... nt_Art.xls

[bernbrue]

thx, Volker

[Infernal_Death]

So after receiving the board i am wondering about the transformers. Volker seemed to have used the Sowters. I am sure they are nice but also pretty expensive.
Now i am wondering if you can substitute the 4383 with the Edcor XSM600/10K and the 8940 with the Edcor XSM6K/600 ? Although i just realized that the XSM6K/600 isn't listed on the edcor site anymore, just in the price list i received from TonyDB some time ago so i have to ask if it's even available anymore. Also if it's even a good choice to substitute a 5k/600 with a 6K/500. Don't know how sensitive the circuit is.

The Edcors are supposed to be of good quality and you can get all 4 transformers for the price of 1 sowter so that's definitely attractive. Otherwise i have to postpone this project as i really don't have the money for the sowters right now.

Flo

[bernbrue]

Flo,
was thinking about that as well. The other day I saw the "Tube Recording Channel" from Michaels "Tegeler Audio Manufaktur" using OEP as Input- and Edcor as Output-Transformer. The VK1s were already such expensive that another project with 300 bucks for the transformers only seems hard to afford. I'll try to get the T4b for us, build the pcb and case and wait and see.
regards
Bernd

[[silent:arts]]

you find an interesting read here:
http://www.prodigy-pro.com/forum/viewtopic.php?t=22288

for the Jensen mod they use a 10K:10K at the input ...

[bernbrue]

Hi,
just scored these transformers:



two for the price of one new.
regards
Bernd

[bernbrue]

Hi,
could look like this:




regards
Bernd

[[silent:arts]]

Looks good, but the Power Switch in the middle ???
and remember: to fit it in a 2U case, modifie the sockets of V104 / 204 (while you are there do V102 / 202 too).

[waldorfcave]

I started to stuff the nice pcbs.

Can i use 1/4 Watt resistors or should they be 1/2Watt as written in the
drip manual

r229,r129 and r134, r234 are 3 watt as written in the parts list.

[[silent:arts]]

I used 1/4 Watt wtih no problems.
and I used 2W (with spacers) instead of 3W - they get a little hot, but it works.

[bernbrue]

to fit it in a 2U case, modifie the sockets of V104 / 204 (while you are there do V102 / 202 too).

Hi Volker,
for the tube sockets, what exactly do I have to do with them? Removing upper or lower part to reduce their height?
I've got these sockets:


regards
Bernd

[[silent:arts]]

just remove the upper part (dremel works well):

[bernbrue]

Ah, I see, I thought I had to remove the upper part of the ceramic socket, so the upper parts of the pins have to be removed. Thx Volker.
regards
Bernd

[[silent:arts]]

yes, only the upper part parts of the pins
gave me the 3 mm I needed (when using 5mm spacers - and is case dependent)