Hafler DH220 Input Board Bottom Photo

[jamesmichael]

Would someone please send me a photo of the Hafler DH220 circuit board etch design. A scan of the board bottom would do just fine.

Just about everything else is available online at hafler.com. I noticed someone at DYI had shown a photo of the DH500 board. I have a DH200 that works for the most part except for 2 volt DC offset in one channel. I figured it would be fun to upgrade the input boards to the DH220 which has a DC offset control. I am going to use this amp in an old solid state organ, so improving sound is not my top priority. However, I would like to have both channels working before it goes into the organ (I plan to biamp which is another advantage of the 220 board.) I could use the original 200 boards with some jumpers and extra drilled holes. I would rather avoid that.

The organ has a fine one watt amplifier. However, no one sells highly efficient 12 inch coaxial speaker anymore.

[Variac]

There might be lots of HAfler input boards available soon.
Here is a current project that is replacing the boards with a completely new design. Only 20 watts/ ch so might not work for you, but lots of people will be geting rid of the stock boards I'd think.

http://www.diyaudio.com/forums/showt...167#post724167

Almost every Pro sound speaker maker still makes highly efficient coax speakers perfect for your application.
Try Eminence, PAudio, Ciare, McCauly, Radian, Selenium, etc. The list is huge. The prices from cheap to expensive. They have them with whizzer cones and with a separate high frequency horn that screws in the center.

There is a thread about Best 15" pro driver for audio that you could search on for more manufactutrers.

[jamesmichael]

I did buy Eminence's most efficient coaxial 12 inch speaker with tweeter. It has a really cool tweeter that screws throught the woofers magnet on the back. The organ one watt amp is no where near what these speakers need. It is amazing how efficient speakers were 40 years ago.

The Hafler 200 and 220 are 100 watts on two sides and 300 watt bridged amplifiers. I am going to replace the PC-6 input boards on the DH200 with the PC-19C input boards used on the DH220. I plan to build the PC19C input boards myself. I have the schematics and part layout. All I need is the copper etching for the PC19C. The PC-19B I found in a separate thread on this site is close. However, It would be nice to have the "C" version on hand.

[jamesmichael]

I found the answer to my own question. Sorry for wasting anyones time who might have been trying to help me. The top portion of the Hafler PC-19C copper layout is in the DH220 manual at the parts layout. I thought this was an incomplete layout since I did not know the PC-19C has a two layer (top and bottom) layout. The bottom copper layout is in the Hafler DH500 manual which also uses the PC-19C layout. I am now on my way to making two of these boards. All of these manuals are at www.hafler.com

[ouimetnick]

Did you ever make those two boards?

[bach911]

Yes, I made boards for both channels. I have been using the hafler now for over five years to drive ribbon tweeters in a three way system for my stereo (theres a term you don't hear much these days).

I used and old spray on negative photo resist. It can't be found anymore. I now use film negative resist. The film and all parts were purchased at Mouser, though I now use Digikey. I replace the power capcitors and bridge.

I posted as a new user since I did not remember my old name. It has been a while since I posted here.

[ouimetnick]

Originally Posted by bach911

Yes, I made boards for both channels. I have been using the hafler now for over five years to drive ribbon tweeters in a three way system for my stereo (theres a term you don't hear much these days).

I used and old spray on negative photo resist. It can't be found anymore. I now use film negative resist. The film and all parts were purchased at Mouser, though I now use Digikey. I replace the power capcitors and bridge.

I posted as a new user since I did not remember my old name. It has been a while since I posted here.

Do you have the layout on a computer? I could use the toner transfer method. Or did you hand draw?

[bach911]

Let me know if this is OK. It is to scale for and 8.5 by 10 inch paper. This was obtained from the mauals available on the internet and enhanced by Photoshop

[eyoung]

I have a pair of DH220 boards NOS never been soldered on 20USD plus postage...if any one is interested

regards, El

[ouimetnick]

Originally Posted by eyoung

I have a pair of DH220 boards NOS never been soldered on 20USD plus postage...if any one is interested

regards, El

PM sent!