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Combined Onaudio thread. (23 threads)

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I'm IN for 2..

Yes, I want in! :)

1. Check to see that there are PCBs left
CHECK
2. Add your name to the list
nakamoomin
3. Indicate number, max 2
2
4. Make a donation of $20 to finance the next free PCBs(You automatically qualify for them) info@harrisonaudiolabs.com

DONE
5. Paypal $6 shipping or send shipping account with a provider such as UPS or FEDEX (PCBs will ship within 24 hours)info@harrisonaudiolabs.com
DONE
6. Pick a project for the next free PCBs from the collection of available amplifiers i.e SYMEF, 1DIFFQC etc(winner will be by total votes)
HAL OPB looks interesting!

- Is there a BoM-file from DigiKey/Mouser/etc available for this project yet?
- Will there be?
 
By the way, what you want to achieve? One audio amplifier with low THD or... ?

First, you should improve VAS amplifier diagram. Then, the output triple tends to be more prone to local parasitic oscillations than the darlington. You can eliminate this disadvantage, but not entirely, by mounting in the bases and collectors of the transistors Q1 and Q11 of 10 ... 15 ohm resistors. Then, the input is not properly optimized because the resistors R17, R29, R3 and R4 voltage falls too much. Typical aims to sweep more than 25mV. In this case, an optimal value for these resistors should be 20 ... 24 Ohm. Then, the most efficient way to eliminate noise input circuit may be done but after a few tests on prototype. In this respect, constructive way PCB has an important role.
 
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