$175 Class D amp--120 wpc

jtwrace · « **Reply #160 on:** 30 Jan 2010, 04:02 pm »

Quote from: OzarkTom on 30 Jan 2010, 03:56 pm

Thanks for the pictures jtwrace. If I can see all the details, and yours gave me plenty of clues, I just will probably try it myself. The circuits of these amps looks so simple, that could be the reason for such great sound.

Less parts=better sound. I have believed in that philosophy for over 30 years.

If you look closely to the Channel Island's D100 mono amps for $1600 a pair, these circuits look very similar to those. And those amps never get bad reviews.

http://www.ciaudio.com/D100.html

No problem. I'd more more then happy to take more if you need some. I also agree with your philosophy.

jtwrace · « **Reply #161 on:** 30 Jan 2010, 04:04 pm »

Quote from: steve k on 30 Jan 2010, 04:01 pm

Enjoy, my friend!!

Steve,

Thanks...I already am.

jtwrace · « **Reply #162 on:** 30 Jan 2010, 04:22 pm »

This is with the volume at 80dB and listening to rock.

This is the Amp draw from the Class D amp.

Watts=10w (my 300wpc Class A amps idle at 600w)

poseidonsvoice · « **Reply #163 on:** 30 Jan 2010, 04:26 pm »

Be a DIY'er

Control your destiny!

See...you don't have to spend kilodollars to get great sound.

Thanks for the update jtwrace. Heh...aren't you a neighbor in NC? Near Charlotte?

Anand.

jtwrace · « **Reply #164 on:** 30 Jan 2010, 04:29 pm »

Quote from: poseidonsvoice on 30 Jan 2010, 04:26 pm

Be a DIY'er

Control your destiny!

See...you don't have to spend kilodollars to get great sound.

Thanks for the update jtwrace. Heh...aren't you a neighbor in NC? Near Charlotte?

Anand.

Yes sir. Huntersville to be exact

steve k · « **Reply #165 on:** 30 Jan 2010, 05:03 pm »

Quote

Watts=10w (my 300wpc Class A amps idle at 600w)

How warm does your amp get at that load?
steve

nodiak · « **Reply #166 on:** 30 Jan 2010, 05:31 pm »

Thanks Avionic. I'm generally following your build from the pic you posted. Bought the switch/fuse holder from ebay. I like the idea of adding vol. pot directly to this amp, will see what develops.
Good thread.
Take care, Don

chadmat · « **Reply #167 on:** 30 Jan 2010, 05:43 pm »

Following this thread with interest and have now ordered one of the kits. Quick question, from looking at the pics, where did you builders ground the amplifier? From the IEC inlet ground terminal with a wire to the chasis? Sorry if I missed the ground in the pics, just curious how builders are grounding so I can finish my assembly plans in advance of the kit arriving.

Regards.

steve k · « **Reply #168 on:** 30 Jan 2010, 05:45 pm »

Quote

Following this thread with interest and have now ordered one of the kits. Quick question, from looking at the pics, where did you builders ground the amplifier? From the IEC inlet ground terminal with a wire to the chasis? Sorry if I missed the ground in the pics, just curious how builders are grounding so I can finish my assembly plans in advance of the kit arriving.

I asked Tom this and he said it doesn't really need grounding but if you want to he recommended grounding to one of the heatsink screws underneath the amp board.
steve

jkelly · « **Reply #169 on:** 30 Jan 2010, 05:55 pm »

What are you guys liking for Chassis RCA's and Speaker Posts?
How about internal wiring cable?

thanks,

Jeff

jtwrace · « **Reply #170 on:** 30 Jan 2010, 06:01 pm »

Quote from: steve k on 30 Jan 2010, 05:03 pm

How warm does your amp get at that load?
steve

The heat sinks on the Class A get to 130*F

steve k · « **Reply #171 on:** 30 Jan 2010, 06:08 pm »

Sorry I meant the Class D.

jtwrace · « **Reply #172 on:** 30 Jan 2010, 06:15 pm »

Quote from: steve k on 30 Jan 2010, 06:08 pm

Sorry I meant the Class D.

Not very. I can measure if you would like.

steve k · « **Reply #173 on:** 30 Jan 2010, 06:18 pm »

I was curious how warm your heatsink gets being much higher powered amp than mine. Mine barely gets warm even at high volume.

jtwrace · « **Reply #174 on:** 30 Jan 2010, 06:27 pm »

Quote from: steve k on 30 Jan 2010, 06:18 pm

I was curious how warm your heatsink gets being much higher powered amp than mine. Mine barely gets warm even at high volume.

Yes, ours are the same.

steve k · « **Reply #175 on:** 30 Jan 2010, 06:55 pm »

Are you driving 4 ohm speakers?

6SN7 · « **Reply #176 on:** 30 Jan 2010, 06:58 pm »

I wanted to keep my enclosures as small as possible while still being able to have easy access to all the components, so this is what I came up with. The box in front, which is without one side, shows the shelf that both boards are attached to--back to back. A larger top lid will cover the transformer and the output board, and a smaller bottom "lid" will cover the power supply board. A front plate will accommodate two switches, marked "on" and "off" and "mute" and "play". Three colors of LEDs will indicated what's going on.
Bob

jtwrace · « **Reply #177 on:** 30 Jan 2010, 07:07 pm »

Some more pics. Keep in mind that this is for the 600w version using XLR balanced inputs. I don't want anyone to hurt themselves or their equipment by following these pictures. Consult your manual or email Tom.

Power Supply Board from 400VA Antek Transformer:

Speaker Board-using XLR inputs:

XLR Panel Mount Jack / Speaker Jacks. These parts I got at Radio Shack. I wanted to make sure that I liked it before spending more money on "high end" stuff.

XLR Balanced Jumper on speaker board:

jtwrace · « **Reply #178 on:** 30 Jan 2010, 07:10 pm »

Quote from: steve k on 30 Jan 2010, 06:55 pm

Are you driving 4 ohm speakers?

They are minimum 4.7 @ 70Hz.

steve k · « **Reply #179 on:** 30 Jan 2010, 07:15 pm »

Looks good Bob!! Can't wait to see the faceplate. The main difference between Bob's case and mine is mine has the tranny mounted vertically like the Channel Islands monoblock layout. It's really amazing how compact these boards are. Since they run at a frequency of 400kHz, the signal paths must be as short as possible.
steve