Matrix M-Stage amp review: simple, cheap, and excellent. - Page 236

Originally Posted by Chris J 

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.

Originally Posted by Chris J 

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.
 

Originally Posted by jc89 

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!

Originally Posted by hifimanrookie 


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..

Originally Posted by Chris J 

 

Nobody wants two different volumes from left and right! 

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.

 

Originally Posted by Wild 






As far as headphones go, it's mostly for people with differing levels of hearing between their ears.  For example, I'd say I have maybe 85% hearing with my left ear compared to my right.  All I have to do is adjust the balance a bit towards the left speaker and voila my hearing is magically fixed 

Originally Posted by hifimanrookie 


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

Originally Posted by muxamed 

 

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

Originally Posted by Chris J 

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

Originally Posted by chicolom 

 

I find the oscillating gives a neat surround sound effect to the soundstage.

Originally Posted by chicolom 

 

I find the oscillating gives a neat surround sound effect to the soundstage.

Originally Posted by Chris J 

You or the Op Amp?

Originally Posted by chicolom 

 

If we oscillate together the effect is stronger.

Originally Posted by burrrcub 

Something's wrong with my mstage.  I was sitting here and I started to smell something burning and started to sniff around.  No smoke coming out but an obvious burning smell coming out of my amp. I opened it up and the burnt smell is stronger but I dont' know which part of the board.  Everything looks fine to me.

Originally Posted by Chris J 

never a good thing, is it still under warranty?

 

what happened before the burning smell?

Originally Posted by Chris J 

sounds kinda kinky