Tangent cMoy amp is very quiet
Oct 2, 2013 at 4:56 AM Thread Starter Post #1 of 10

recordbreakor

New Head-Fier
Joined
Oct 2, 2013
Posts
6
Likes
0
Hi everyone! I just completed making the cMoy amp according to Tangents tutorial. I went to play music and realized that it is extremely quiet. I can barely hear it at the highest volume. I don't know what's wrong with it. I checked all of the connection and they seem fine
I know it's not the cleanest soldering job but it doesn't have any bridges. I even switched out the chip. Should I just start over or is there still hope?
 
Oct 2, 2013 at 6:17 AM Post #2 of 10
If you can hear sound then you've probably connected everything up correctly. You could have inappropriate values though.
 
Tell us the type of phones and the source. Is the volume acceptable driving the phones directly from the source if this is possible?
 
w
 
Oct 2, 2013 at 5:19 PM Post #3 of 10
I'm just using some cheap Sony X something something. It doesn't take much to drive them. The power source is my iphone 5S and the OPA2132PA . I don't necessarily know what you mean in your last sentence but the volume is controled by the phone and a radioshack pot
 
Oct 2, 2013 at 6:39 PM Post #4 of 10
I know it's not the cleanest soldering job but it doesn't have any bridges.

 
I see carbonized flux. That's a conductive path. If this is the problem, cleaning the board can fix it.
 
What I don't see is the top-side picture or the measurement results I asked you for via email.
 
  If you can hear sound then you've probably connected everything up correctly.

 
Not necessarily. The weak virtual ground in the CMoy can be "bounced" by the source, conveying tiny amounts of sound to the output.
 
The power source is my iphone 5S

 
That's your audio source only, surely.
 
But it brings up a good question: what are you using to power the amplifier?
 
Oct 3, 2013 at 8:47 PM Post #7 of 10
I see carbonized flux. That's a conductive path. If this is the problem, cleaning the board can fix it.

What I don't see is the top-side picture or the measurement results I asked you for via email.


Not necessarily. The weak virtual ground in the CMoy can be "bounced" by the source, conveying tiny amounts of sound to the output.


That's your audio source only, surely.

But it brings up a good question: what are you using to power the amplifier?


Also, if the flux was conductive, and I powered up the amp, do you think I shorted out anything?
 
Oct 3, 2013 at 9:09 PM Post #8 of 10
Also, if the flux was conductive, and I powered up the amp, do you think I shorted out anything?

 
If the flux was conductive, and you powered up the amp, you certainly shorted something out. 
 
Get a new multimeter so you can diagnose your own problems. 
 
Oct 4, 2013 at 3:54 AM Post #9 of 10
I am using a single 9v battery to power it.


Well, there's one problem for certain: you've got both C1 caps oriented the same direction. Re-read the second paragraph of Stage 1 in the assembly instructions.
 
The backwards cap should be replaced. It's probably damaged.
 
You might also consider using the virtual ground strips on the board to connect those green wires together, instead of using a free-floating solder blob. You're less likely to accidentally short something out that way.
 
I can't get any measurement results right now because my Multimeter it broken 

 
Well, maybe you have only one problem with this build, and I have found it. If there's more than one problem, the lack of a meter means you'll just be guessing about it. And without that measurement data, you'll be asking us to guess about your guesses.
 

Users who are viewing this thread

Back
Top