Another GainKlone is alive and singing!

[overmind]

My pair GainKlone mono block is alive and singing! Initial testing is very good, no hissing and huming. Good bass, a bit up front and not very at ease, will need some tunning.

I used the non-inverting configuration, with a 4.7uF ERO MKP input cap, input resistance of 50kOhm. I make the gain of the amplifier to be 13 (1 + 621k/49.9k). Temporary power supply is a +/- 22Vac transformer, IRF 40CDP100 Schottky Diodes as rectifier. Nichicon KZ 1000uF 50V along with Wima MKP10 0.22uF 160V by pass cap, another ERO MKP1839 1uF 160V bypassing the +Vcc and -Vcc.

Added two Nichicon KG 15000uF/63V to the power supply, do not like the effect, even more unrelax. Took them off. What else can I do to make it sound more relax?

Oh yes, "heat sinks" are also DIYed. I posted more pictures in my website, check it out.
http://www.geocities.com/overmindxx/


Regards,
SW Yeo

[jan.didden]

Hi Yeo,

You had me worried there for a minute! "Singing" most of the time is used to indicate oscillations. Glad yours is OK!

Jan Didden

[carlosfm]

...but have you posted a picture?
I can't see anything, only two icons.
Anyway, you don't say what power op-amp you used.
Give us a clue.
And you can try the inverted Gainclone, maby that's the problem.
Or circuit layout.
Do you have the psu caps near the chips?
My Gainclone is not upfront...

[overmind]

Originally posted by janneman
Hi Yeo,

You had me worried there for a minute! "Singing" most of the time is used to indicate oscillations. Glad yours is OK!

Jan Didden

It is not "singing", but performing nicely.

Originally posted by carlosfm
...but have you posted a picture?
I can't see anything, only two icons.
Anyway, you don't say what power op-amp you used.
Give us a clue.
And you can try the inverted Gainclone, maby that's the problem.
Or circuit layout.
Do you have the psu caps near the chips?
My Gainclone is not upfront...

I have problem uploading the pictures, I linked them from Pbase. Anyway, I tried attach the pictures again. The IC I am using is LM3875.

Regards,
SW Yeo

[overmind]

Picture 2

Check out my website for more picture postings.
http://www.geocities.com/overmindxx/

Regards,
SW Yeo

[fedde]

Wowie, from which planet are they ???

Nice.

1. Try swinging instead of singing
2. Try the inverting configuration WITH an appropriate resistor on the +input. (621 k in your config)
3. Try more gain. (eg. 20 k <-> 621 k)

Fedde

[karma]

looks great . your website is still down o now its up


how hot do thay get?

[overmind]

Originally posted by fedde
Wowie, from which planet are they ???

Nice.

1. Try swinging instead of singing
2. Try the inverting configuration WITH an appropriate resistor on the +input. (621 k in your config)
3. Try more gain. (eg. 20 k &lt;-&gt; 621 k)

Fedde

Swinging - learned
I just wonder what is effect of gain or the level of feedback on the sound for this amp. Will try to increase the gain.

Originally posted by karma
looks great . your website is still down o now its up


how hot do thay get?

geocities - free web hosting, there is a limitation of web traffic of the website. It is free, what to do.

How hot they depand on the type of music is being played. If I am listening to pop with lots of bass, then it get a bit warm. For Jazz and classical, it will take about one or two hours of operation before a slight temperature rise can be felt with my hand. Of course, it will depend on the volume/output level. BTW, I am using the amps with Proac 2.5, which is not really a difficult load for the amps.

Yeo

[overmind]

Schematic of my amplifiers. Please advice.

Yeo

[overmind]

the bottom view of the amp.
Yeo