• 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 Round 2

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

toufu

Member
Joined 2008
Hi guys, what's the best way to bias the BPA150? Is the goal to have all three chips output 0? If I change one, the others change as well. Short of having three multimeters, how could one do it easily?

By the way, the sound is awesome, I am not missing the F5 that it's replacing at all. It's got way more bass and just more powerful sounding without losing the clarity and detailness.
 
S

shmulik

Member
Joined 2004
measuring the PA150

has anyone completed a set and connected signal generator on one end and a oscilloscope on the other (besides Alex)? I did and have not managed to both get a square wave without ringing and constant gain well over 20KHz. I can reduce ringing by enlarging the feedback capacitor but this hampers on the frequency response. I must have a systematic error on all boards or some other error in the devices around (PS? what can go wrong with a transformer diode bridge and a pair of capacitors?).
To emphasize, I test an insulated board with signal generator directly connected to its input and a scope on its output - no bridge configuration. the square wave is in low frequencies.
the result of having a decay in gain towards 20KHz is a "slow" and somewhat fuzzy amplifier.
 
T

toufu

Member
Joined 2008
shmulik said:
has anyone completed a set and connected signal generator on one end and a oscilloscope on the other (besides Alex)? I did and have not managed to both get a square wave without ringing and constant gain well over 20KHz. I can reduce ringing by enlarging the feedback capacitor but this hampers on the frequency response. I must have a systematic error on all boards or some other error in the devices around (PS? what can go wrong with a transformer diode bridge and a pair of capacitors?).
To emphasize, I test an insulated board with signal generator directly connected to its input and a scope on its output - no bridge configuration. the square wave is in low frequencies.
the result of having a decay in gain towards 20KHz is a "slow" and somewhat fuzzy amplifier.
Click to expand...


I completed mine, and I am getting a little high frequency hiss and noise, is that what you are talking about?
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom