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Re: Class D Audio KIt ordered!

Posted: Fri Mar 11, 2011 11:39 pm
by Fran
Looking good Claus.


Might be worth connecting the Tx to the PSU board, firing her up and checking the voltages before connecting the amp board.


Looking good though!!!


Have you decided on a colour for the box?

Re: Class D Audio KIt ordered!

Posted: Sat Mar 12, 2011 11:23 am
by Claus
I might just bring a can home from work. So most likely a colour that wasn't too popular around the christmas plays last year. ;)
Good idea on the Tx...
I seem to get some alu stuck in my bits (don't take out of context please!). Any tips?

Re: Class D Audio KIt ordered!

Posted: Sat Mar 12, 2011 12:47 pm
by Fran
In the drill bits? Just use a small screwdriver or similar to poke the swarf off. Next time if you spray a little bit of WD-40 on the area first, you won't get that. A lot of small motor factors will have spray cans of acrylic paint for 5-7 euro, a can of colour and a can of lacquer is your friend. You'll need to sand out any scratches first - and loads of light coats are better than one heavy one.



Fran

Re: Class D Audio KIt ordered!

Posted: Sun Mar 13, 2011 8:47 am
by Claus
Thanks Fran, your tip helped on the drill bits! All wired up and ready for the speakers to be connected. I used the silver in Teflon I had from my umbilical project, for signals. It fired up ok last night and just glad I double checked everything: I had connected two wires wrong, but discovered it. Will let you know how it sounds later ;)

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I measured the two gain potentiometers and set them to the same value at around 12 o'clock. ClassDaudio recommend setting them between 11 and 2 o'clock. Of course if I find a value that suits I can always put in a permanent resistor, so plenty of room for a little tweaking there.

Re: Class D Audio KIt ordered!

Posted: Sun Mar 13, 2011 12:35 pm
by Fran
Good stuff, now measure for mv dc at the outputs (dc offset), might as well measure ac as well - that will give you a figure for hum.

Lastly measure ps output under load, check the heatsinks temp after some play time.

Re: Class D Audio KIt ordered!

Posted: Sun Mar 13, 2011 1:58 pm
by Ivor
Looking good Claus.

Re: Class D Audio KIt ordered!

Posted: Sun Mar 13, 2011 4:46 pm
by Claus
Fran wrote:Good stuff, now measure for mv dc at the outputs (dc offset), might as well measure ac as well - that will give you a figure for hum.

Lastly measure ps output under load, check the heatsinks temp after some play time.
Only saw this now. ;)

Had it up and running for around 10 minutes. All sounds great and seem to work as intended.

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Very easy project except for the drilling etc. that I have NO experience with.
Thanks again to Fran for the help and case.

Re: Class D Audio KIt ordered!

Posted: Sun Mar 13, 2011 6:23 pm
by Rocker
Great work Claus, well done. Not much wrong with your metalwork either!

Re: Class D Audio KIt ordered!

Posted: Mon Mar 14, 2011 3:36 pm
by cybot
Well done Claus, long may she run :-)

Re: Class D Audio KIt ordered!

Posted: Sun Mar 20, 2011 9:35 am
by Claus
Have had it on for a couple of days and thought I would share some listening experiences. My only real listening references are my main system and the old home studio active Roland monitors.

The old Roland monitors sounded extremely thin and lifeless which was the main reason for my upgrade. The PMC DB1+ monitors are very neutral sounding but has great bass response for their size. I hooked them up to my main system when I first got them and they filled out my living room quite well. Great level of detail and not a bad sound stage either. Of course they could't produce the lifelike vocals in the mid range or the real deep bass notes of my LFT-8 speakers.

The immediate differences when hooked up to the new class d audio amp are not subtle: Using my laptop (macbook pro) as a source and Digidesign rack 003 interface. The sound is now much more, what I can best describe as, "metallic". Now this is compared with the BAT cd player and Musical Fidelity M3 Nu-vista amp so obviously not a fair comparison. The speaker cables are also new and just home made CAT 5E so that might have an impact as well. I will let the system settle in a bit longer and keep you posted. It would be interesting to see how the class d amp compares to a similar powered amp (50 - 150 watts say) in a great system. So if anyone has a balanced preamp, and would like a to try it out, I would be happy to bring it around for a listen.