• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

BPA300 mono block

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
T

tryonziess

Member
Joined 2007
here is a picture during the final test. i will build the chassis this weekend. not sure if i am going to make two separate monoblocks in one case or make two separated cases.
 

Attachments

  • bpa 004.jpg
    bpa 004.jpg
    36.6 KB · Views: 831
A

alexw88

Member
Joined 2004
shine7.com/audio/audio.htm
tryonziess said:
has anyone had any luck connectin the s`ingle ended leads directly to pcb for bridge operation. i connected the ground to one + input the the positive to the other + input. my amps sound fantastic with only the cd player driving them. i have a balanced sound card on my computer and will try it next. how is the transformer project going alex
Click to expand...

It is good that you get rid of the noise.

When you connect like this and with single ended input source, you are essentially using only one PCB, which gives 150W max.

I am working on a balanced pre-amp now, after that is done I will try the transformer in my power amp. The transformer is better driven by an active preamp.
 
T

tryonziess

Member
Joined 2007
alex88. anytime i get the drv134 setup even close to the amp project it creates excess noise. i am going to have to work on this or go with the transformer. these units are incredible sensitive to stray signals. i am going to go back through the drv setup and see if something is not right or make a new one. i got the boards from digi01 and they seem to be well made. i still have some excess heat in one bpa150 module. it is not too bad just hotter than the one next to it.
alexcd, i am having problems getting my pictures to be accepted by the forum specs. i will send a few closeups once i get them shrunk to 105k for forum rules.
 
T

tryonziess

Member
Joined 2007
alexw88.. got the caps right where you show them on your amp. i have just enough space under the board for the caps and some air. alex i noticed that the mounting holes at the top of the board go right thru the power traces. i had to install insulating washers at those two standoffs so there was no chance of shorting. just in case some other builders have not noticed.
when i get this project done does anyone want to buy a really nice mcintosh mc2250 amp. i will not need it any longer. alex how about designing a nice 400 watt discrete class ab amp and sell some boards. something good to maybe 1 ohm continuous load. serious now i want to build a good set of discrete mono's i only started this hobby 6 months ago. i do not know a whole bunch but a lot more than when i started. thanks to all of you folks.
 
T

Tex Houston

Member
Joined 2007
Variable resistors etc

Hi Alex - is it possible to use 100k VR's instead of 50K? i may hace difficulty sourcing correct surface mount components here - is it possible to substitute standard components? I am planning on using 2 boards in a stereo set up with a single transformer - what is the minimum value transformer that you would recommend?
thanks!
 
T

tryonziess

Member
Joined 2007
sprocket, that is how many i have. ain't it grand. let me check how much i paid alex for them. where are they to be shipped so we can add a tiny bit of postage. i initially planned on building 4 mono blocks or paralleling alex's original design with an extra pair. however, the final result of just the original circuit is great. i am also considering just running parallel instead of bridged. you will like this build. alex did a good job. i am off to a discrete symasym next to try it out. tad
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom