It looks great, and I really like etching one's own PCBs.
One thought, you might move the Rg closer to the FET. This is something I didn't do in my early PCBs and I've gone back and made the changes (jumper and Rg on the FET) to control parasitics.
Modification instructions -
The current PCB have been found to be needing one extra resistor added to get the bias set to a range where the amp will make it’s full designed power. This is a minor compensation for the particular small-signal transistor (ZTX450) and will be integrated into new revisions of the PCB. In the meantime, you will need to add this resistor above the PCB.
It is going to be very helpful to have a 2nd person to help you hold things in place as you solder.
The end result should look like this -
First take the 2.2K resistor and bend the lead around a small screwdriver.
The resistor will go here - don’t cut anything yet, but try to bend the leads so they go in the approximate correct location.
Trim and solder
Be sure that the resistor lead touches only the first leg of the transistor.
With the other end attached to the transistor, bend and trim the opposite lead.
Solder. Repeat on other amp channel.
The current PCB have been found to be needing one extra resistor added to get the bias set to a range where the amp will make it’s full designed power. This is a minor compensation for the particular small-signal transistor (ZTX450) and will be integrated into new revisions of the PCB. In the meantime, you will need to add this resistor above the PCB.
It is going to be very helpful to have a 2nd person to help you hold things in place as you solder.
The end result should look like this -
First take the 2.2K resistor and bend the lead around a small screwdriver.
The resistor will go here - don’t cut anything yet, but try to bend the leads so they go in the approximate correct location.
Trim and solder
Be sure that the resistor lead touches only the first leg of the transistor.
With the other end attached to the transistor, bend and trim the opposite lead.
Solder. Repeat on other amp channel.
and mine is up and running, for 22 hours now, no problems just beautiful beguiling sound . . .
I have to now finish the enclosure, but just enjoying the sound too much!! have an external PSU 120 VA toroid, 60 000 uf 20 volts!! I can keep my fingers on the heatsink for about 12 seconds or so!!
I have to now finish the enclosure, but just enjoying the sound too much!! have an external PSU 120 VA toroid, 60 000 uf 20 volts!! I can keep my fingers on the heatsink for about 12 seconds or so!!
Attachments
I was wrong, 9V voltage is not sufficient to allow a constant current source to achieve constant results, but sounds good.
finally i got my aca boards!
if anyone's interested in recycling: i took 2 old g4macminis trashed everything exept alucase and powersupply, gave the thing a new butt and crowned it with old alufins.
voilá
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4856.jpg
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4859.jpg
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4861.jpg
if anyone's interested in recycling: i took 2 old g4macminis trashed everything exept alucase and powersupply, gave the thing a new butt and crowned it with old alufins.
voilá
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4856.jpg
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4859.jpg
/Users/attilacsete/Desktop/AmpCampAmp/IMG_4861.jpg
I'm thinking about buying the kit for xmas, but i'm afraid of only 6 Watt. I'm not a pro at DIY, i cannot measure volume level etc.
My speakers are these with 90db/1w
https://www.intertechnik.de/Shop/La...usaetze-mit-Eton/_BS-DUETTA_1768,de,2668,6075
can i have some fun with it or is it just like "background" music ?
My speakers are these with 90db/1w
https://www.intertechnik.de/Shop/La...usaetze-mit-Eton/_BS-DUETTA_1768,de,2668,6075
can i have some fun with it or is it just like "background" music ?
I just finished mine, they are currently in my main system, I'm running PSB Alpha B1's which are 91db@1w and they get plenty loud. I haven't tried them with my Tekton 8.1's yet which are 97db@1w. The PSB's are great speakers but don't have much down low so I'm running an extra set of wires off the amps to the high level inputs on my sub. These little amps sound fantastic.
This amp with that bias mod is really loud. I found that I don't need more power, and I use a B1 as a "pre". However, you can hear the the amp has a bit higher THD compare to bigger FW amps, especially on higher volumes. If you listen to simple enough music, you will newer notice, but I am a huge Steve Vai fan 
. Don't get me wrong this is a really nice sounding amp, I put it way above F5 for example. And the bass, it will surprise you... But I have a better PSU, can't say about ones from that kits.
Some more pictures of finished amp:
. Don't get me wrong this is a really nice sounding amp, I put it way above F5 for example. And the bass, it will surprise you... But I have a better PSU, can't say about ones from that kits.Some more pictures of finished amp:
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