Questions regarding building the CMoy

[Q00 0]

look around at mustafa center..got sum there

[tropicalrips 0]

got this from link posted by Jtfoo, the drawing is only showing 1 side of the circuit rite? so i just follow the same path for the other side? i take it that the power side is still the same as the Cmoy

will different op-amps work?

Edited November 19, 2003 by tropicalrips

[N@Z 0]

Wouldn't it be cool if you could put it in something like this. Easy to replace the battery, assuming the 9v can fit in it.

[jtfoo 0]

got this from link posted by Jtfoo, the drawing is only showing 1 side of the circuit rite? so i just follow the same path for the other side? i take it that the power side is still the same as the Cmoy 

will different op-amps work?

Yup, diagram is for one channel only. So for stereo, you'll need 2 pieces of dual opamps. Different opamp should work and that's the fun for opamp rolling. But take note the opamp that is gonna be used for the buffer has be unity gain stable. Check the datasheet of the opamp if it's stable at unity gain. The OPA2134 should be stable at unity.

 

Power can be the same circuit as cmoy, maybe you want to increase the elco cap to 470uF.

Edited November 20, 2003 by jtfoo

[augustineRS 0]

altoids can be found at mustafa for $2.50.

taste good too

[huangyong 0]

hey guys, share with you something, i have built cha47 (no ground channel) using JR4556, without cap, gain =5.8 .

 

it's fantastic, warm tube(y) sound, detail, relaxing, but soundatge a bit small.. i think add in a 5.1uF Solen cap will solve the sound satge prob.

 

i personally thnik that that amp really goes well with my AKG K501, it not just tame it's brightness, but also provide BASS to it. if you are using bright headphones, i strongly recommend you try this. it's cheaper than building using 2 opa2134.

 

I don't want to compare it with my PMPPA coz......

[N@Z 0]

altoids can be found at mustafa for $2.50.

taste good too

That's a good price actually.

[tropicalrips 0]

i hav 2 spare opa2132 op-amps, i think i will use those first, i found "hudson's" mint tins they look quite good too has a retro look they look a little longer then the Altoids that should giv more room for the Cha47.

by the way why is it call "cha47" anyway

if i add my own design to it can i call it "rip47"

[jasonhanjk 0]

 

I don't want to compare it with my PMPPA coz......

cos not ready?

[jtfoo 0]

i hav 2 spare opa2132 op-amps, i think i will use those first, i found "hudson's" mint tins they look quite good too has a retro look

Hudson mint box it just nice for the cmoy + Battery and all sockets. I had my cmoy in a Hudson mintbox too.

 

[tropicalrips 0]

tied out the cha47 layout on the proto-board, it sounds good now with low impedance phones, no more hiss with 16ohm cheap-po testing earphones

i change the gain resistor to 3k instead of 4.7k for more gain on higher impedance cans

does that mean its longer a "***47"

i think this tread is getting too long, can we make it a sticky? so it will be easier for others to find & learn

Edited November 20, 2003 by tropicalrips

[jasonhanjk 0]

Normally a sticky contains important element and not so much talk around. Maybe you can start a new thread with everything it is needed to build a cmoy, etc.

 

Just my 2 sen.

[Mackie 0]

I concur with Jason. Admin and mods will always welcome informative threads and convert them to stickies. Technical information as discussed in this thread is best collated and presented on a new one so readers do not have to peruse through all the posts to attain whatever information he's after.

Edited November 21, 2003 by Mackie

[augustineRS 0]

Just to check with you guys.

Just started on my Cmoy.

Resistors value giving me problems.

Looking at so many sites I still can't see what are the correct values for the resistors.

Can you guys like give me some ideas.

R1 - R5 use what values?

R5 is optional?

 

Thanks.

 

In addition I think should really make it into a sticky.But then again, is whether anyone(mods/admins ) going to clipped the thread or start a whole new one.

[N@Z 0]

Why don't someone make something offline first then post a dedicated thread. If it is clipped off this thread continuity of discussion will be gone. As Jason & Mackie has mentioned this thread doesn't really qualify as a sticky because it's a mish mash of information & there is not alot of specific detailing for a newbie to be able to start from scratch.

 

Although other articles exist on Headwize, Head-Fi & Tangent's websites. I believe it is a good idea to have a dedicated one which exist to serve SG & regional members. where the thread could include sourcing the relevant parts available closer to home, equivalent parts etc. The person who is really interested can collate & add all the relevant information into one thread. It might be a good idea also to get input from other DIYers to discuss the matter further so that all avenues could be addressed.