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Matrix M-Stage amp review: simple, cheap, and excellent. - Page 235

post #3511 of 4884
Yes, the Q701 needs more gain than the ERP4 which is more efficient.
post #3512 of 4884

Thanks.

Setting it to 20dB, the Q701 still sounds funny, and ER4P is unbalanced: left side is a lot more upfront than right.

 

I will probably try to go to a local stereo store and find a better source to test Q701 again...

Since it requires more power than ER4P to drive, it's possible that the distortion and amplification of source noise is much bigger, and thus the source needs to be much cleaner.... But based on what I read on this forum, that shouldn't be so dramatic... But again, I am not expecting different gain settings would mess up ER4P's balance, so anything is possible and only trial and error can tell...

 

Will definitely report back when I do have a chance to test again.
 

post #3513 of 4884
Quote:
Originally Posted by jc89 View Post

Thanks.

Setting it to 20dB, the Q701 still sounds funny, and ER4P is unbalanced: left side is a lot more upfront than right.

 

I will probably try to go to a local stereo store and find a better source to test Q701 again...

Since it requires more power than ER4P to drive, it's possible that the distortion and amplification of source noise is much bigger, and thus the source needs to be much cleaner.... But based on what I read on this forum, that shouldn't be so dramatic... But again, I am not expecting different gain settings would mess up ER4P's balance, so anything is possible and only trial and error can tell...

 

Will definitely report back when I do have a chance to test again.
 

 

This is very strange indeed. If you had the imbalance in both the headphones and earphones it would be easy to track down. Good luck! 

post #3514 of 4884

This is probably not it, but are you sure it's not the headphone socket on the M stage?-Occasionally my K701 sounds weird and unbalanced when i first plug them in, but when i give the headphone jack a little spin in the socket it becomes normal again..

Just thought i would mention it. smile.gif

post #3515 of 4884
Quote:
Originally Posted by musicbased View Post

This is probably not it, but are you sure it's not the headphone socket on the M stage?-Occasionally my K701 sounds weird and unbalanced when i first plug them in, but when i give the headphone jack a little spin in the socket it becomes normal again..
Just thought i would mention it. smile.gif
If tats the case then its faulty..it must be having bad connection to the board..i would contact seller and ask for repair/replacement.
post #3516 of 4884

yeah i know.regular_smile%20.gif

I'm looking into it. Just thought it might be a possible answer for jc89's problem too.

post #3517 of 4884

You save my day!!

The problem is Q701's 3.5mm to 1/4 inch converter that comes with it!

 

I changed it to the old one coming with my AKG 240, and it solves the issue! It works with DT880's converter, too.

 

I'm so stupid.... in retrospect, the cause was quite obvious, when Q701 sounds better through iphone's 3.5mm headphone jack than M-stage's 1/4 inch output....

 

Thank you musicbased!

 

This is quite dissapointing on AKG's part... Good thing the headphone itself is not a lemon, just the converter...


Edited by jc89 - 1/19/13 at 3:22am
post #3518 of 4884

about the unbalance... it's completely due to my noobiness and carelessness...

 

I didn't realize that the two sets of gain controls are controlling left and right channels separately... I thought they are for input 1 and input 2 separately.

 

I'm confused by this design though... Why would anyone want to have different volumes coming out from left and right sides?

Are there any technical reason for this design? 

 

 

Thanks!

post #3519 of 4884
Quote:
Originally Posted by jc89 View Post

about the unbalance... it's completely due to my noobiness and carelessness...

I didn't realize that the two sets of gain controls are controlling left and right channels separately... I thought they are for input 1 and input 2 separately.

I'm confused by this design though... Why would anyone want to have different volumes coming out from left and right sides?
Are there any technical reason for this design? 


Thanks!
I dont know also...maybe just a joke of the designer?..but check my amp..its even worse!..i even have two volume knobs, two on-off switches and even two power cables..lolz.. biggrin.gif
post #3520 of 4884
Quote:
Originally Posted by hifimanrookie View Post


I dont know also...maybe just a joke of the designer?..but check my amp..its even worse!..i even have two volume knobs, two on-off switches and even two power cables..lolz.. biggrin.gif

 

Many other amplifiers have this same design on the gain switches. 

post #3521 of 4884
Quote:
Originally Posted by jc89 View Post

about the unbalance... it's completely due to my noobiness and carelessness...

 

I didn't realize that the two sets of gain controls are controlling left and right channels separately... I thought they are for input 1 and input 2 separately.

 

I'm confused by this design though... Why would anyone want to have different volumes coming out from left and right sides?

Are there any technical reason for this design? 

 

 

Thanks!

 

Nobody wants two different volumes from left and right!  wink_face.gif

They would have to use a more expensive switch than the little switches you see on the bottom of the M Stage.

So you could say it keeps the costs down.

Most people set gain to 10 dB with Q701 and leave it there.....forever.

 

I just compared 5 different phone pre-amps, they all have that funny feature: separate switches for left and right.

It's even worse, because you can adjust:

input resistance

input capacitance

pre-amp gain

subsonice filter

but all switches are separate for left and right! 

But once you set the switches the way you want them, you never change them unless you change to another phono cartridge.

 

Seems to be  mark of passage for M Stage owners, they all need to mix up gain settings.

  beerchug.gif

post #3522 of 4884

Jc89, glad you got it figured out. Now open the case, remove the opamp, and replace with 637AP. I bet you'll like what you hear.

post #3523 of 4884
Quote:
Originally Posted by etys rule View Post

Jc89, glad you got it figured out. Now open the case, remove the opamp, and replace with 637AP. I bet you'll like what you hear.

 

Do NOT do this!

 

Under certain conditions (Gain set to 0 or 10 dB) the Op Amp will probably oscillate.

 

Stick to the OPA627 or any other unity gain stable Op Amp.

post #3524 of 4884
Quote:
Originally Posted by Chris J View Post

Do NOT do this!

Under certain conditions (Gain set to 0 or 10 dB) the Op Amp will probably oscillate.

Stick to the OPA627 or any other unity gain stable Op Amp.
To do or not..the opa627 sounds almost the same as opa637..and yes..the opa637 CAN oscillate on lower gains..its wellknown..it gets stabile on 18db and forth... So in my opinion the opa627 is a good update choice biggrin.gif
post #3525 of 4884
Quote:
Originally Posted by Chris J View Post

I like what Mux says, the LM4562 is a good upgrade for the M Stage, I've tried a few Op Amps, including the OPA 627 and I prefer the LM4562.
 

 

I don't know though if the amp gets hotter with LM4562.

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