btol
New Head-Fier
- Joined
- Apr 24, 2012
- Posts
- 10
- Likes
- 10
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[size=medium]Hi Everyone,[/size]
[size=medium]I’m a newb and am putting together a CMOY headphone amp for the first time. I’m using Tangent’s instructions found here: [/size][size=medium]http://tangentsoft.net/audio/cmoy-tutorial/[/size][size=medium]. I just started soldering a few weeks ago and don’t even know how to properly use a multimeter – at least in terms of measuring/testing circuits or connections as recommended in some of the troubleshooting threads out there. The only experience I have with mods is successfully desoldering the opamp out of an Onkyo CD player, soldering in a socket for opamp rolling, then inserting a new opamp into the socket. Since I was very pleased with those results, I thought I’d step it up a notch and try to build the CMOY. [/size]
[size=medium]I got through stages zero and one as described by Tangent and all was well. I executed the test at the end of stage one and the multimeter showed that I had positive DC voltage at the positive cap and negative voltage at the negative cap. Magnitudes were practicially identical and the LED turned on.[/size]
[size=medium]I just finished stage 2 and running the test for this stage revealed a problem. As instructed, I hooked a source up to the amp then the amp to headphones via alligator jumpers. The good news is I get no heat but the bad is that when I turn the source’s volume (my iphone) up, at around half way, the sound starts to become really distorted and unlistenable. The higher I go with the volume the worse it gets. I’m not sure if this is clipping or distortion or what. All I know is that the sound breaks up once I reach half way on the volume adjust.[/size]
[size=medium]Does anyone know what I might have done wrong? You’ll find pictures of both the top of the board to show component placement and the bottom to show my soldering. Hopefully that will help with figuring out where I goofed. I really thought I was being super diligent about making sure I placed components in the right holes and generally following Tangent’s instructions so I’m not quite sure what the issue is. It doesn’t really help that I have no electronics knowledge either.[/size]
[size=medium]One thing that I suspect may be at least part of the problem is the fact that I deviated from Tangent’s instructions in one place. Instead of using OPA2132PA for the opamp, I used a NJM5532D opamp. It is the old opamp from the CD player that I modded (as mentioned in the first paragraph above). I figured it was just sitting around so why not use it? Do you guys think that could be causing the distortion and a quick fix would be to replace it with Tangent’s recommended OPA2132PA?[/size]
[size=medium]Many thanks for your help with yet another newb trying to make a CMOY amp.[/size]
[size=medium]B[/size]
[size=medium]Hi Everyone,[/size]
[size=medium]I’m a newb and am putting together a CMOY headphone amp for the first time. I’m using Tangent’s instructions found here: [/size][size=medium]http://tangentsoft.net/audio/cmoy-tutorial/[/size][size=medium]. I just started soldering a few weeks ago and don’t even know how to properly use a multimeter – at least in terms of measuring/testing circuits or connections as recommended in some of the troubleshooting threads out there. The only experience I have with mods is successfully desoldering the opamp out of an Onkyo CD player, soldering in a socket for opamp rolling, then inserting a new opamp into the socket. Since I was very pleased with those results, I thought I’d step it up a notch and try to build the CMOY. [/size]
[size=medium]I got through stages zero and one as described by Tangent and all was well. I executed the test at the end of stage one and the multimeter showed that I had positive DC voltage at the positive cap and negative voltage at the negative cap. Magnitudes were practicially identical and the LED turned on.[/size]
[size=medium]I just finished stage 2 and running the test for this stage revealed a problem. As instructed, I hooked a source up to the amp then the amp to headphones via alligator jumpers. The good news is I get no heat but the bad is that when I turn the source’s volume (my iphone) up, at around half way, the sound starts to become really distorted and unlistenable. The higher I go with the volume the worse it gets. I’m not sure if this is clipping or distortion or what. All I know is that the sound breaks up once I reach half way on the volume adjust.[/size]
[size=medium]Does anyone know what I might have done wrong? You’ll find pictures of both the top of the board to show component placement and the bottom to show my soldering. Hopefully that will help with figuring out where I goofed. I really thought I was being super diligent about making sure I placed components in the right holes and generally following Tangent’s instructions so I’m not quite sure what the issue is. It doesn’t really help that I have no electronics knowledge either.[/size]
[size=medium]One thing that I suspect may be at least part of the problem is the fact that I deviated from Tangent’s instructions in one place. Instead of using OPA2132PA for the opamp, I used a NJM5532D opamp. It is the old opamp from the CD player that I modded (as mentioned in the first paragraph above). I figured it was just sitting around so why not use it? Do you guys think that could be causing the distortion and a quick fix would be to replace it with Tangent’s recommended OPA2132PA?[/size]
[size=medium]Many thanks for your help with yet another newb trying to make a CMOY amp.[/size]
[size=medium]B[/size]
