[Darvy]

Well I built myself a cmoy. Surprised I actually got it since I have absolutely no clue about electronics.

Anyway I got some Alligator jumpers and did everything Tangent describe (thanks Tan).

Since I'm new at this and my soldering isn't quite up to par yet, I was wondering if its possible for all the sounds to be okay but the cmoy is broken. Like somehow the current flows to the headphone but the amp itself is broken.

The reason I ask this is because the sound quality seems to be the same. Well I'm actually running the cable through my onboard sound on my computer so that might be the reason. Also for the 1/8 inputs (I used Tangent recommendation), I clip on the alligator jumpers onto them and it seems that the left/right channels seem to be on reverse. Its probably just the jack itself but is it generally left, right, and ground in this order?

I'm pretty new at this so pardon for my n00b questions.

The headphone I'm using is the Sony MDR 3K (can't afford an amp after this

)

Thanks for the help. I'm about ready to box this up tomorrow. I hope to move onto Primeta sooon.

 

[IdiotTech]

Well i hope that you didnt use those sonys to test out the amp for the first time. You can do some damage to the phones like that.

 

[robbneu]

Darvy,

I'm the furthest thing in the world from an expert (see how many posts I have under my belt!), but could you elaborate a little on what you mean by "the sound quality seems to be the same." When using the amp are you getting an increase in volume? Or, is it exactly the same? When I put together my first C-Moy (the Tangent flavor) I had used the wrong posts on the jacks and got a slightly tinny, almost AM-radio sound from the amp. When I grounded the jacks properly, the sound was drastically different.

Robb

 

[Darvy]

Quote:

Originally Posted by IdiotTech Well i hope that you didnt use those sonys to test out the amp for the first time. You can do some damage to the phones like that.

Naw I have really cheap 20 dollar headphones. I used those first

 

[Darvy]

Quote:

Originally Posted by robbneu Darvy, I'm the furthest thing in the world from an expert (see how many posts I have under my belt!), but could you elaborate a little on what you mean by "the sound quality seems to be the same." When using the amp are you getting an increase in volume? Or, is it exactly the same? When I put together my first C-Moy (the Tangent flavor) I had used the wrong posts on the jacks and got a slightly tinny, almost AM-radio sound from the amp. When I grounded the jacks properly, the sound was drastically different. Robb

They sound about the same. Yea I had the AM-radio low quality thing too but after messing with the grounding alligator the sound came out

 

[robbneu]

Hmmmm. Well, as I said, I'm certainly no expert. Maybe someone else has some ideas for you, because I can really only speak from my own experiences with building the C-Moy and this isn't anything I encountered.

Some of the differences in sound quality can be subtle, depending on your source and the quality of your headphones, but at the very least you should be getting a boost in volume.

Robb

 

[Earwax]

maybe this will help on the jack (ignore the sloppy soldering)

green = ground
red = right
black = left

 

[nkd]

It's possible that the two jacks are connected to each other, so the amp circuitry isn't being used at all. Check all the connections with a multimeter.

 

[Darvy]

Quote:

Originally Posted by nkd It's possible that the two jacks are connected to each other, so the amp circuitry isn't being used at all. Check all the connections with a multimeter.

I think you just hit the nail in the coffin with this comment. When I was messing with the alligator jumper I have to put it in a way that the jumper kind of touch the other sides although they both have to be connected.

Now if you don't know. How do I go about exactly checking up the the connections with the multimeter? I mean what should I see to know if they're connected to each other or not? Pretty n00b question I know

.

 

[Darvy]

Quote:

Originally Posted by Earwax maybe this will help on the jack (ignore the sloppy soldering) green = ground red = right black = left

thanks for that pic. Looks like I did mine totally backward or my jack is designed that way.

 

[Earwax]

Quote:

Originally Posted by Darvy thanks for that pic. Looks like I did mine totally backward or my jack is designed that way.

The jack I used is the one from Digikey on Tangent's part list. There should be an schematic available on DIgikey's site, or just plug a cable in and use your meter to see which tab connects to each part of the cable.

 

[gnuZ]

Quote:

Originally Posted by Darvy Well I'm actually running the cable through my onboard sound on my computer so that might be the reason.

This is probably the reason why it sounds the same. Crap in = crap out. Use a higher quality source such as a DVD player or maybe even buy a better soundcard if you want a computer-based system, especially with audiophile headphones such as the CD3000's.

 

[nkd]

Just turn your multimeter to measure resistance. If the lines are connected, it should show either 0 or maybe an actual value (if they're connected by a resistor for example). If not, then the display will show no change.

The real test for whether the two jacks are connected or not though it to try to change the volume.

 

[Darvy]

Quote:

Originally Posted by nkd The real test for whether the two jacks are connected or not though it to try to change the volume.

I don't quite get that last part. If the volume changes then ? And well I'm directly connect to the computer with a cable so I control volume from the computer.. I don't exactly understand how that fit into the whole grand scheme of things.

 

[nkd]

Well if you can control the volume from the amplifier, then it's working. In your case that would probably mean changing a resistor, so it may be more effort than it's worth