[gjavitt90]

hey,
I've built about 3 cmoys at this point, and the sound i have to admit is not that astounding. I think the problem is that the sources I'm using aren't that good, and the cmoy can't make a source sound better that it already does. What I want to know if the amps i see here talked about (pimeta, ppa, millete max, beta22, m3, m^3, etc.) can actually make the source sound better than the source actually is. the earphones i have are ksc75, and er6i. Don't hold anything back because you think i can't build it, i wanna learn it all.

-gabe

 

[heatmizer]

put simply
garbage in garbage out

 

[j4cbo]

Yep, garbage in, garbage out; if you have a bad source, the solution is to get a better one.

What are you using now? There are a number of nice DIY USB DAC designs out there.

 

[gjavitt90]

for portable a creative zen pmc, for desktop a dell inspiron 2650

 

[MisterX]

Garbage in = garbage out is only half of the story.
If your cans are turds at some point you just have to realize shining them is an exercise in futility
(both of the cans mentioned are great choices in their respective categories but neither of them scale very well IMO)

 

[Logistics]

Which parts, exactly, did you use to build your cMoy?

 

[balou]

yep, parts selection in a cmoy matters quite a bit, especially opamp selection

 

[gjavitt90]

for the first cmoy i used tangent's website to the dot. for the others i found a local electronics store for the caps and resistors and stuff, the board from the shack, and for opamps i've tried a lot. I got the opa2132/opa2134 and the opa2277, and the ad8397, i also tried the cheap ones like tl072 and tl073

 

[tomb]

Certain tube amps that are colored can improve a poor recording a bit. The SOHA comes to mind. The coloration from the reduced tube plate voltage combined with its high gain gives it a very strong bass punch that's not unlike a car subwoofer - the bass is there whether it's in the signal or not.

At the same time, the opamp output stage with its current limitation tends to smooth out harshness and dynamics (with the right opamp). So, it can "jazz up" some mediocre mp3 recordings.

That's not intended to be a criticism of the SOHA - just that it can be an example answer for the OP's question. I find the SOHA with mp3's and KSC75's to be a very pleasurable combination, if not the most accurate.

I agree with the other posters - most high end amps (pretty much all the solid-state ones) ruthlessly reveal any defect and shortcoming in a recording/source.

 

[gjavitt90]

@tomb: but i guess what you're talking about is adding more sound to the source. I wanted to know if there are opamps out there that know what would sound bad, based on pitch or frequency or something, and be able to not include it in the output. judging on what everyone's said here, it seems like that would not be possible.

Thanks for you time anyway.

 

[Logistics]

Perhaps you should state what you are using as sources. They can be improved upon as well.

 

[vixr]

I dont know all the reasons behind it, but I find playing with the gain in a CMoy can have a large effect on the sound quality. Source volume too...

 

[pinkfloyd4ever]

what sound card do you have in your dell? If it's a soundblaster or x-fi you could do cotdt's mod. I'm about to do it on my SB, which isn't as well documented as the x-fi mod so let me know if you end up doing that. Also, are you using the front panel HP jack? b/c I've read on here that the SQ of the front panel jack is nearly always inferior to the one in back on the soundcard

 

[gjavitt90]

okay, I'm not sure why someone revived this thread but whatever. the source as i said is my dell laptop, not some pcmcia card or usb, integrated. but i plan on buying this usb sound card http://www.newegg.com/Product/Produc...82E16829612001 it got pretty good reviews there, and it's pretty cheap. as for adjusting the gain on cmoys, the first had a gain of 11 with a potentionmeter, the second a gain of 6, and the third a gain of 2 with resistors in the r5 positions, which was meant for the er6i's.

 

[threepointone]

on crappy opamps. . .anyone tried a 741 in a cmoy yet? O_O