Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Dual CMOY Amplifier Idea, will it work?
New Posts  All Forums:Forum Nav:

Dual CMOY Amplifier Idea, will it work? - Page 2

post #16 of 27
10/8/09 at 12:21am
Thread Starter 
Quote:
Originally Posted by Koyaan I. Sqatsi View Post
Ah, yeah. That'd work. Your dongle would have a four pin female XLR on one end and a 6.3mm TRS on the other and if you stuck with the ipso facto four pin "standard," then pins 2 and 4 get tied to the ground sleeve of the 6.3mm TRS.

se
That's what I was thinking it'd be. Honestly it wouldn't surprise me if on single entry headphones if the ground wire from the right ear cup met the ground pole on the left hand speaker directly and then had another wire proceed from there to the TRS connector.

That's why I was confused and was hoping for a different answer or an explanation. :P
Reply
post #17 of 27
10/8/09 at 1:42am
Quote:
Originally Posted by Aynjell View Post
Okay, how does one go about making a balanced version of any given amplifier? I'd be interested in trying this, and is it easy to make an adapter from balanced to a 6.3mm or 3.5mm? I'd be interested in trying the balanced idea for next to nithing, and the A47 looks like it could pull that off. It looks really interesting in a ghetto-fi way.
I certainly do "ghetto-fi."

Few people have tried "entry-level" balanced designs owing to the fact that the more sage and wise folks usually council such money could go longer getting you into a better single-ended setup. If you're on a budget and already have a balanced source, though (I got my E-mu 1212m used for $75), it's really not that difficult to implement. My balanced a47 was dirt-cheap to build, but it was certainly more than a small improvement over my vintage NAD Preamp headphone stage (which was no slouch, either). My modded 555's out of the balanced setup are tighter, noticably more detailed, and have notably better bass response--which might be another reason such a set-up might be desirable for your AD700's. FWIR, *both* the 555's and the AD700's have been reviewed to be bass-light, especially unamped. I don't consider my 555's "bass-light" anymore!

Another benefit? I'm using a ultra-el-cheapo switching power supply, my rail-splitter looks like it was assembled by Dr. Frankenstein, and just look at my rats-nest wiring implementation. Nothing very pretty...

...but it's quiet. Dead-of-night quiet. No noise whatsoever.

Quote:
...I despise the idea of dual XLR and I'd use a single 4 pin XLR.
4-pin is certainly more elegant. I actually used dual 1/4" TRS plugs since I had limited space...and the TRS plugs were cheap.

Beware you may have space issues at the XLR strain-relief depending on what you recable with. Be sure to research carefully before you buy your cable/connectors.

Quote:
Can anybody link me to some good information for making balanced setups?
Start here:

Balanced audio - Wikipedia, the free encyclopedia

Google is your friend.

One final warning, though: Remember the resale value for your AD700's will drop as soon as you start modding them. Be sure you're committed to this course before you start down the path.
Reply
post #18 of 27
10/8/09 at 1:53am
Thread Starter 
Quote:
Originally Posted by Zaubertuba View Post
I certainly do "ghetto-fi."

Few people have tried "entry-level" balanced designs owing to the fact that the more sage and wise folks usually council such money could go longer getting you into a better single-ended setup. If you're on a budget and already have a balanced source, though (I got my E-mu 1212m used for $75), it's really not that difficult to implement. My balanced a47 was dirt-cheap to build, but it was certainly more than a small improvement over my vintage NAD Preamp headphone stage (which was no slouch, either). My modded 555's out of the balanced setup are tighter, noticably more detailed, and have notably better bass response--which might be another reason such a set-up might be desirable for your AD700's. FWIR, *both* the 555's and the AD700's have been reviewed to be bass-light, especially unamped. I don't consider my 555's "bass-light" anymore!

Another benefit? I'm using a ultra-el-cheapo switching power supply, my rail-splitter looks like it was assembled by Dr. Frankenstein, and just look at my rats-nest wiring implementation. Nothing very pretty...

...but it's quiet. Dead-of-night quiet. No noise whatsoever.



4-pin is certainly more elegant. I actually used dual 1/4" TRS plugs since I had limited space...and the TRS plugs were cheap.

Beware you may have space issues at the XLR strain-relief depending on what you recable with. Be sure to research carefully before you buy your cable/connectors.



Start here:

Balanced audio - Wikipedia, the free encyclopedia

Google is your friend.

One final warning, though: Remember the resale value for your AD700's will drop as soon as you start modding them. Be sure you're committed to this course before you start down the path.
I got them for 60$, it can't get any lower I don't think, and the resale value doesn't matter if I intend to keep them.

One quick question, do you require a balanced source to use a balanced amplifier?
Reply
post #19 of 27
10/8/09 at 2:16am
Quote:
Originally Posted by Zaubertuba View Post
Start here:

Balanced audio - Wikipedia, the free encyclopedia

Google is your friend.
Keep in mind that almost none of that is relevant to many so-called "balanced" amplifiers. "Balanced" amplifiers that are nothing more than pairs of bridged amplifier channels while technically "balanced" in terms of impedances, do not provide the raison d'etre of balanced interfaces, i.e. common-mode rejection, and really shouldn't be called "balanced" amplifiers. Instead, they should be called "bridged" amplifiers, and this would be a more appropriate reference:

Bridged and paralleled amplifiers - Wikipedia, the free encyclopedia

se

Reply
post #20 of 27
10/8/09 at 2:23am
Quote:
Originally Posted by Aynjell View Post
One quick question, do you require a balanced source to use a balanced amplifier?
If your "balanced" amplifier is just a bridged amplifier, then you pretty much either need to feed it from a balanced source, configure one of the bridged channels as an inverting amplifier, or just drive one side of the bridge and ground the input of the other side.

se

Reply
post #21 of 27
10/8/09 at 1:19pm
Thread Starter 
After looking around, I really like the idea of the mini^3 for my next project, once finished it'll look polished, it'll have a wall charger and wall power capable, and it's still portable. I'll probably go the extra mile afterwards and mate it with the y1 dac, in the same case so I have two similar looking boxes.

But that's the route I've decided to take, I think, at least for now.
Reply
post #22 of 27
10/8/09 at 1:36pm
Coolness!

Good luck!

se

Reply
post #23 of 27
10/8/09 at 2:31pm
Quote:
Originally Posted by Aynjell View Post
After looking around, I really like the idea of the mini^3 for my next project, once finished it'll look polished, it'll have a wall charger and wall power capable, and it's still portable. I'll probably go the extra mile afterwards and mate it with the y1 dac, in the same case so I have two similar looking boxes.

But that's the route I've decided to take, I think, at least for now.
That really is awesome!

Sometimes it takes quite a bit of searching around before you settle on your next project. I'm glad it took you considerably less time--I think it took me about 3 months to figure out what my next route is going to be.

Good luck as well.
Reply
post #24 of 27
10/8/09 at 3:05pm
Thread Starter 
Quote:
Originally Posted by Zaubertuba View Post
That really is awesome!

Sometimes it takes quite a bit of searching around before you settle on your next project. I'm glad it took you considerably less time--I think it took me about 3 months to figure out what my next route is going to be.

Good luck as well.
After that I'll probably move to a Y2 + M3. And then I'll produce a B22.

Is it worth my time to order it from Glass Jar audio, or can I save 10-15$ sourcing the parts myself?
Reply
post #25 of 27
10/8/09 at 4:53pm
Quote:
Originally Posted by Aynjell View Post
After that I'll probably move to a Y2 + M3. And then I'll produce a B22.

Is it worth my time to order it from Glass Jar audio, or can I save 10-15$ sourcing the parts myself?
Well you are following my plan . I built a mini3 + gamma1 and love it. Great little project and sounds great. I am now almost done with my Y2 + M3, I have the Y2 complete and the Sigma11, just need to get the M3 together.

I did not use Glass Jar for the mini3, but only because at the time I did not know it existed. I would think you would be hard pressed to beat his price for the mini3 kit, and many headfis have reported nothing but good things about him (I have not used Glass Jar so can not comment on it).

Have Fun.
Reply
post #26 of 27
10/8/09 at 5:03pm
As Jeff at Glass Jar buys the parts in bulk, he tends to get better prices then you will get by your self.

I bought an AlienDAC from him last year and was very happy with the service.
Reply
post #27 of 27
10/8/09 at 5:45pm
Thread Starter 
Quote:
Originally Posted by cobaltmute View Post
As Jeff at Glass Jar buys the parts in bulk, he tends to get better prices then you will get by your self.

I bought an AlienDAC from him last year and was very happy with the service.

I'm double checking the pricing, I'll be building 2 at a time, so I am not sure of this entirely. Unless I'm missing some seriously crazy expensive part or two, I'm looking at maybe 140$ for two... that's about a 40$ savings. 20$ for 2 batteries, 50$ for the parts from mouser (roughly), and about 50$ for the parts from AMB themselves. I'm going to do some more checks and balances on it tonite and figure it all out and make sure I have a fill BOM and price it out, that's why I said 140$, leaving about 20$ of wiggle room for parts I forgot to add to cart and shipping.

140$ is right on par, giving a 40$ bonus to me sourcing my parts myself. That'd almost buy me a bantam dac kit from their site. I say the benefit of ordering myself is very real. Granted, I haven't added the leds to my cart but how expensive can it? Even for a single amplifier, this is a 20$ premium.
Reply
New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Dual CMOY Amplifier Idea, will it work?