Mezmerize DCB1 Building Thread

Mosfet substitution

Salas,

I hate to ask this if it has been answered some where else, but here goes.

I bought several parts kits from Teabag for the Salas SSLV1.1 BIB and I have some kits left over that I thought at the time I could use in the Mezmerize DCB1 and Hypnotize boards.
Of course the Mosfets are different and was wondering if I could plug in the IRF9610 / IRF610 and IRF9530 / IRF530 Mosfets in place of the IRFP9240 and IRFP240 Mosfets? If so, what other resistor values need to be changed?

Thanks as always for your help.

By the way, I am building your: Salas Simplistic NJFET RIAA using the Salas SSLV1.1 BIB regulators boards and the Mezmerize DCB1 for the preamp/selector and finally an electronic crossover using the B1 type buffers in a 24 db per octave 2 way crossover. I will use a pair of the Hypnotize boards (one per channel) to power all the B1s in the crossover (8 per channel), see attached, all in one case,
I will build an out-board case for the transformer with bridges, rectifiers and caps.

Your thoughts are alway appreciated.

Rush
 

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It does not seem like it will be oscillating if you keep everything the same but the Mosfet types, its compatible theoretically. Take care to insulate the TO-220s well, they aren't as easy for that as the TO-247s. It will be a bit higher impedance, certainly not put together and critically judged for a DCB1 as a whole in the development stage, can be good enough I guess, don't know more. Certainly cheaper and a tad uglier.:D
Good luck with the assortment as a total, and keep us posted.
 
It does not seem like it will be oscillating if you keep everything the same but the Mosfet types, its compatible theoretically. Take care to insulate the TO-220s well, they aren't as easy for that as the TO-247s. It will be a bit higher impedance, certainly not put together and critically judged for a DCB1 as a whole in the development stage, can be good enough I guess, don't know more. Certainly cheaper and a tad uglier.:D
Good luck with the assortment as a total, and keep us posted.

Thank you Salas,

Whoa! You said the magic words, "higher impedance" "good enough", I will use the original design with IRFP9240 and IRFP240 Mosfets.

Any body need 5 pos and 5 neg Salas SSLV1.1 BIB kits as sold by Teabag's group buy? Free shipping in USA.

Rush
 
At last, manage to finish my mesmerize and listen to it. It is very relax and open sound paired with my elektor mini crescendo amp. Thank you to Mr. Salas for the design and help. Also thanks to Ed for those hard to find relays. I finished building my hypnotize board but decided to built the mesmerize first because I had a suitable enclosure for mesmerize size.
 

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Last edited:
Offset Problem

Hello,

I´ve finished my Mezmerize DCB1.
The measurements are:
- 9,8V
+10,31V

DC-Offset
R -2,2mV
L -37,1mV :confused:

Every part is matched and measured before soldering (the LED sets and SK170
are from Ed).

What could be the reason for this bad offset?
Do I have to change some LED´s.

DCB1 02.jpg

Thanks for your help

Andreas