F5 power amplifier

[maxwell007]

Guys, is it BOM for V3.0 board available? I think BOM for V2 is not fit..

 

[6L6]

Work from the schematic, BOM have a tendency to be inaccurate after a few months.

 

[maxwell007]

you're knowledgeable in this forum, can you please insert here schematic for V3 .. in DIY store is for V2

 

[labjr]

I think the circuit is on page 2 of the F5 Turbo manual.

http://www.firstwatt.com/pdf/art_f5_turbo.pdf

 

[maxwell007]

OK thanks

 

[6L6]

Schematic in this is for v3 - http://www.diyaudio.com/forums/pass-labs/254056-f5turbo-illustrated-build-guide.html

 

[BigE]

Work from the schematic, BOM have a tendency to be inaccurate after a few months.

Like are the resistors 1/2 watt or 1/4 watt?

 

[maxwell007]

Here is F5 V3.0 schematic, and BOM which I edited from previous version... If someone interested...

 

[flg]

But, that is not a "Turbo" F5 version? That would be page 9 of the Turbo manual: http://www.firstwatt.com/pdf/art_f5_turbo.pdf
The F5 Clone PCB Version 3 is here: http://www.diyaudio.com/store/amplifier-circuit-boards/power-amplifiers/f5-circuit-boards-208.html And the schematic from that page is : http://www.diyaudio.com/forums/imag...n/P-F5-1V20/P-F5-1V20-schematic-revision1.pdf But called V2? And the BOM is apparently "Under Construction"?

 

[maxwell007]

schematic, which I already post is for F5 V3, not Turbo... Turbo version is with two output pairs....

 

[maxwell007]

Some closer look at V 3.0 boards. I used Panasonic power resistors, and 0,6W 0,1% tolerance for the rest..

 

[6L6]

Like are the resistors 1/2 watt or 1/4 watt?

Either is fine, except for the ones with big pads (source resistors, feedback resistors), there you need 3W.

 

[labjr]

Nice work Maxwell.

 

[stijn001]

But, that is not a "Turbo" F5 version? That would be page 9 of the Turbo manual: http://www.firstwatt.com/pdf/art_f5_turbo.pdf
The F5 Clone PCB Version 3 is here: F-5 clone boards (2 PCBs, makes 2 channels; Rev 3.0) - Power Amplifiers - Circuit Boards And the schematic from that page is : http://www.diyaudio.com/forums/imag...n/P-F5-1V20/P-F5-1V20-schematic-revision1.pdf But called V2? And the BOM is apparently "Under Construction"?

Same confusion I ran into about a year ago, when I build mine, ...

DiyAudio store F5 pcb V3, follows the component/numbering of the schematics in the F5T manual (page 2)

 

[acumos]

Hi guys, I'm back. I've solved all problems preventing to finish my f5. Now I've started to bias. I've adjusted at 0.4V, after 30 min to 0.5 and after 2 hrs rebiased at 0.6V. The strange thing is that if power up again the amp, after 30 min it is still at 0.53. What can I do?

 

[Zen Mod]

wait for temp equilibrium

 

[oloppolo]

The sound of my f5 is hard and poor low frequency with my speakers (4 ohm). Improvement can I do?
ACA is very good with same speakers.

 

[BobEllis]

By low do you mean lower SPL at the same volume knob position? The F5 has relatively low gain, you'll need to turn up the volume. One channel or both?

If that doesn't work, assuming your preamp is up to the task, annotate a schematic with your voltage readings. Perhaps there is a fault we can help you diagnose.

 

[oloppolo]

By low do you mean lower SPL at the same volume knob position? The F5 has relatively low gain, you'll need to turn up the volume. One channel or both?

If that doesn't work, assuming your preamp is up to the task, annotate a schematic with your voltage readings. Perhaps there is a fault we can help you diagnose.

My preamp is B1. I have no problem with gain. I have few low frequency both channels.

 

[AndrewT]

post some detailed pics