amps finished!

[coils]

I finished my X-BZLS and 5 watt/ch X-SOZ. I am thrilled with the sound quality! They sound amazing, and I have crappy speakers, and I'm running an unablanced source.

Let me know what you think.

http://members.dslextreme.com/users/amplifier/

X-BZLS specs:
Circuit boards from Kristijan Kljucaric
+,- 50 VDC rails
39K Ohm feedback resistor under main board
2 x 10 uf parallel feedback capacitors
Original spec mosfets
Dual 10K Ohm input attenuator
Single 10K Ohm output attenuators on each output
.250" aluminum plate chasis, with panels from frontpanelexpress.com. .5"
mdf top

X-SOZ specs:
Dual Stancor RT-208 salvaged power transformers, 24.5 VAC @ 8A each, primaries parallel, secondaries parallel
+,- 13.8 VDC rails
CLC filter, 43,000-2mh-43,000 (inductors are x-over filters, seem to work,
but do get hot)
2 x 10K parallel feedback resistors
2 x 220 uF parallel lytic feedback capacitors
IRFP048 mosfets
Outputs to ground = 4.9 VDC

I'm not an electronics tech, nor do I have training, so any advice or constructive criticism is welcome. I may be way off base with my X components, and those are subject to change.

Next project: Horns!

Thad
L.A.

[jleaman]

Great work for sure.. Keep it up..

J'

[PierreG]

Wow! very nice looking job. Thank for the pictures. You now need to build speakers....

[Dr.Gone]

Nice... very nice... I'm certainly not an expert, but just looking at the pictures (and casing), it looks nice!

[kilowattski]

Great job. Nicely Built. Maybe it's me, but by the looks of it, does the top plate fit on the amp without hitting the electrolytics? It could be an optical illusion from your photos.

[Duck-Twacy]

I'm impressed.

Btw how hot do the inductors become?

[eLarson]

Gorgeous chassis work!!!

Did you fabricate it yourself?

[coils]

Thanks for the complements. This was my first amp project, and I was afraid that the 5 watt output might not give much volume, but I was surprised on that note. I now want to build some kind of Horn, which one, I dont know. I like the Lowthers, but I prefer the price point of the Jordan used in the J-Low. What would the consequence be for me to use a 4 ohm speaker like the Jordan. I beleive that I am pushing my power supply pretty hard, I think I have a total of 392 va's.

Originally posted by kilowattski
does the top plate fit on the amp without hitting the electrolytics?

Yes, the caps are about a half inch taller than the chasis. Its dangerous!, I will fab a perferated plat top soon.

Originally posted by Duck-Twacy

Btw how hot do the inductors become?

After 2 hours running, they are hot, but I can leave my finger on them. I'm going to borrow an infrared temp. gun and sample a few select points on the amp, I'll let you know.

Originally posted by eLarson

Did you fabricate it yourself?

Yes, with the exception of the front/back panels, I designed and fabbed both units, I have two shops (machine/wood) at my disposal. I have a chassis just like the preamp slated for a D/A convertor.

[GeorgeBoles]

Hello All,

Could you chappies please let me know where you get those nice rods and bearings to operate switches and pots (traditionally at the rear of pre-amps) from the knobs (traditionally at the front of the pre-amp!)

The response I have received whenever I have asked for items such as these at electronics shops is a befuddled silence and a look of pity. I don't even try to explain about short wire runs for better quality sound, because the the pity usually evaporates into mirth.

Regards,
George.

[wrenchone]

Places that cater to amateur radio operators generally will stock shaft couplers and bearings. You may have to do mail order buying to get what you need.