After multiple digikey and mouser packages, after one big amb package.. i have started my new winter project.

the alpha 10 preamp.. basically it's a backplane board for all the different amb projects. it ties up all the different pcb together into a preamp.

the pictures of a wire free chassis was what sold me on this idea. and the fact that I can replace each module if and when they get upgraded is great.

i think that this is something others can "copy" .. make a generic backplane that you can plug different modules into to make amps, etc

-joe

I have been side tracked lately. not enough time to do the F5 like I wanted.

I ended up digging up the BOM for mini aleph and ordered the parts for that.. started to solder the parts and found that I needed to soldier mount the resistors because they are way too big for the PCB

I need to double check all the blank spots, clean up the flux on the board and start on the power supply..

It's been fun to do simple head amps (RA1 clones) and chip amps (audiosector, chipamp.com) and then move onto 4 chip TDA boards off ebay into big heatsink chassis

Along the way I learned a lot about sourcing parts (a pain), chassis work (bigger pain) and component layout for optimal cable distance and distortion

My last finished project, the b1 buffer, was the best result so far.. it's simple, but it blew away my friends big name preamps.. enough that they are making a shift to DIY their own!

Time is a commodity that a lot of DIYaudio guys lack.. other responsbilities means we have very little time to devote to projects we start and a lot of times projects get drop to the wayside.

My latest project is the F5 and I hope to get it done by the next burning amp meet.. I want to see if I can convince papa to autograph that and the B1

https://hifi4sale.fullboards.com/equi...-amp-t2455.htm

2SK370 N channel JFET Transistor 4x (GR or BL grades)
1N914 Diode
Generic LED
15000 uF 2x Electrolytic 25v
10 uF 2x Film
1 uF 3x Film
1 ohm 3w
1k ohm 4x .25w
10k ohm 2x .25w
15k ohm .25w
25k ohm 2x .25w
221k ohm 2x .25w
1M ohm 6x .25w
2 way switch
RCA jack 6x
Linear Taper Pots 25k 2x

R1 - R2 2 10R 10R - 1% - 0.6W
R3 - R4 - R15 - R16 4 2.2K 2.2K -1% - 0.6W
R5 - R6 - R7 - R8 4 100R - 3W 100R - 3W
R9 - R17 - R18 3 1K 1K - 1% - 0.6W
R10 1 100K 100K - 1% - 0.6W
R11 - R12 2 0.47R - 3W 0.47R - 3W
R13 - R14 2 47R 47R - 1% - 0.6W
R19 - R20 2 150R 150R - 1% - 0.6W
R21 - R22 2 10K to 22K (same value !) 10K to 22K - 1% - 0.6W
P1 - P2 2 5K Trimmer Vishay 64W/Bourns 3296 - 5K - 25 T
Q1 1 2SK170-BL (2SK370) N - Matched Idss
Q2 1 2SJ74-BL (2SJ108) P - Matched Idss
Q3 1 IRF9240P/FQA12P20 P - Matched Vgs
Q4 1 IRF240N/FQA19N20C N - Matched Vgs
Q5 1 ZTX550 (BC560) Zetex or similar - PNP
Q6 1 ZTX450 (BC550) Zetex or similar - NPN
TH1 - TH2 2 4.7K 4.7K - NTC - Thermistor - 3980K

https://www.diyaudio.com/forums/pass-...ml#post1740824