With 24 Volts power supply - you can get max 17 Volts RMS out of that thing.
With a 2 V RMS source and a gain of 15-20 the amp should already be clipping.
Does your power amp have no gain and are your speakers 80db efficient or so?
If your first BA-3 works without issue - there must be something wrong with this one. Either the amp or the attenuator.
You can start with the voltage measurents mentioned earlier. If the attenuator attenautes more than it should or the amp has less gain than expected you know where to look. You can generate test tones for measurement here: tone generator or use a smartphone if you have no function generator function generator app
You can also make comparative measurements with the working BA-3 or switch the attenuators. Maybe some resistors are the wrong value (R10,R11,R13 -maybe 60 intead of 600 or so)
You can start with the voltage measurents mentioned earlier. If the attenuator attenautes more than it should or the amp has less gain than expected you know where to look. You can generate test tones for measurement here: tone generator or use a smartphone if you have no function generator function generator app
You can also make comparative measurements with the working BA-3 or switch the attenuators. Maybe some resistors are the wrong value (R10,R11,R13 -maybe 60 intead of 600 or so)
Ben,
Thanks so much for finding this error.
You are correct. I checked on my purchase order for these resistors: 47Ohm not 47K were purchased.
I will replace them.
I will retain the 10K input resistors on the Khozmo board.
Ben, you should use that image for your identity in the forum. Or we can call you 'old eagle eyes,' which may be offensive since I don't know your age.
The Pre is born. What a journey. Learned a lot [even though this was my 2nd BA-3], veered near the edge but was always pulled back just in time.
Thanks again to Ben and everyone in this great forum [just one of sooo many].
Worse, I checked the resistors and still missed it.Ben is, repeatedly, Hawk Eye
though, I did wrote twice or trice, to fiddle with R2
frankly , I didn't even think of possible error in parts values ...... sometimes I'm forgetting that checking that isn't everyone's routine
Mighty did not say fiddle, Mighty said change R2. Remember, you are not only omnipresent and omnipotent. But also omnicorrectBen is, repeatedly, Hawk Eye
though, I did wrote twice or trice, to fiddle with R2
frankly , I didn't even think of possible error in parts values ...... sometimes I'm forgetting that checking that isn't everyone's routine
This is strange.
I've built two BA-3 amps, let's call them BA1 and BA2.
My source is a Node to an ANK DAC 5.1 that I built a year ago.
My amp is a M2X.
When I feed BA1 via this system all is good.
When I feed BA2 with this system, the right channel comes in about 50% to the left in volume.
When I take the DAC 5.1 out of system to the BA2 and feed the Node to BA2, all is good.
So the DAC 5.1 works with BA1, but not BA2.
I've checked all the connections.
I've run this series of tests multiple times.
The only major difference between BA1 and BA2 is the Khozmo attenuator [which ANK uses in their preamp kit].
I have used two different sets of interconnects.
I have no idea what is going on.
Just want to sit and listen to music at the end of the BA-3[2] build adventure [whine, whine].
Any thoughts would be appreciated.
I've built two BA-3 amps, let's call them BA1 and BA2.
My source is a Node to an ANK DAC 5.1 that I built a year ago.
My amp is a M2X.
When I feed BA1 via this system all is good.
When I feed BA2 with this system, the right channel comes in about 50% to the left in volume.
When I take the DAC 5.1 out of system to the BA2 and feed the Node to BA2, all is good.
So the DAC 5.1 works with BA1, but not BA2.
I've checked all the connections.
I've run this series of tests multiple times.
The only major difference between BA1 and BA2 is the Khozmo attenuator [which ANK uses in their preamp kit].
I have used two different sets of interconnects.
I have no idea what is going on.
Just want to sit and listen to music at the end of the BA-3[2] build adventure [whine, whine].
Any thoughts would be appreciated.
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define exact type of Khozmo
if that is one with fixed series resistor, then shunting resistance as variable, you need to do 2 things:
-first change R2 in BA3 ( Rin defining element) to, say , 330K
-optimize value of series resistor to give you minimal possible attenuation in lowest position
if that is one with fixed series resistor, then shunting resistance as variable, you need to do 2 things:
-first change R2 in BA3 ( Rin defining element) to, say , 330K
-optimize value of series resistor to give you minimal possible attenuation in lowest position