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Starving Student PCB's - Page 13

post #181 of 323

There's been some talk in this thread and else where about a switching power supply's affect on the performance of an amp.  I was thinking of throwing a small board together to 'smooth' out the supply on my Starving Student.  What do you guys think about a pair of 220uF electrolytics and a .1 or .01 film for this.  Any thoughts on these values or its over all worth in general?




post #182 of 323

How do i go about ordering a couple of these?



post #183 of 323
Thread Starter 

You ask me :-)




post #184 of 323

PM Inbound!

post #185 of 323

Received today. Thank you very much..... will get on with ordering the other components and let you know how i get on!


Any tips?

post #186 of 323

Hi mates.
I begin to build an SSMH amplifier.
I wish to know what configuration you recommend to me for a SSMH 12au7:
10K pot and R16 & R17 10K or prefer 50K pot and R16 & R17 50K?
I will use for headphones from 80ohm up to 250ohm.
Thanks on advance.






P.D.(If you can tell me pros and cons, thanks :)  )

Edited by fuens - 3/12/14 at 8:51am
post #187 of 323
Thread Starter 

Someone else posted this and it's a very reasonable explanation


~~Adding a 50K resistors before a volume pot virtually lengthens the resisting surface by 50K. Say you have a 50K pot that you never go over half its rotation range. Adding a 50K resistor before pushes that useless half outside the rotation range (not really on a log pot, but you get the idea). It's effectively stretching the first half of the pot across its whole rotation range. The value isn't important, you chose it after experimenting with your system until you find the right value. It depends on the voltage out of your DAC and the voltage your headphones need.


I use 50k or 47K just make sure you use LOG pots




post #188 of 323

Thanks so much Fred. :beyersmile:





post #189 of 323

So after everything was built, it appears that only the left side is working (right tube doesn't light up and no heat from right mosfet).


Things I tried:


swapping tubes - tubes are fine

resistance/continuity test - so far no problem found


Any idea from here?

post #190 of 323
Thread Starter 

You need to put up some pictures otherwise it could be lots of things


both sides of the board




post #191 of 323



Problem fixed, despite me reminding myself that I need to solder the MOSFET the right way I still manage to f it up.

Edited by Jawmare - 3/28/14 at 1:07pm
post #192 of 323

Can anyone recommend a Pot that is available in the UK?


I have tried to find a stockist for the PDB182-K430K-503A but they all seem to charge £12 shipping from the US!



post #193 of 323


Try to found it on Ebay.

Sure you will find more cheap (item + delivery).

Have luck.





post #194 of 323

Is it normal that after amping vocal shifted to the left?

post #195 of 323

Hi All;


Finally finished my Starving Student.  If I had to describe this project with one word, it would be 'surprise'.  With no break in, this thing sounds good even with my cheap break in phones.

Here are a few pictures of the final product.




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