[draven5494]

The Auzentech is a warm sounding laid-back unit (I used to own one) compared to many other DACs. The ODAC is on the lean side (comparable to Benchmark DAC1). Try LM4562, it's less strident and more laid back than the stock OPA2132. Biased into class A, the LM4562 gets slightly warm sounding. You can also try OPA2604 or JRC/NJM4556.

You can always EQ.

Thanks for the info Purrin. I definitely agree that the ODAC is leaner than my Forte. It also has superior detail and separation. I probably should have kept my HRT MSII. It is also has fantastic detail without sacrificing bass. I did have issues with static and popping while using WASAPI with that though.

This hobby... It can be frustrating.

Oh well, such is the life of a headphone junkie.

 

[Chris J]

Has anyone used their Q701s with the ODAC connected to the m-stage?  I just hooked up my ODAC today and I am noticing a marked drop in bass quantity compared the DAC in my Auzentech Forte soundcard.

I really do like the detail of the ODAC and would love to keep it if I can get the bass boosted a bit.  I am running stock opamps, so if there are some opamps out there that can boost the bass I am all for trying that.

What do you guys recommend I do to get a little more bass with this setup?

Changing the Op Amps won't boost the bass.

 

[geetarman49]

Quote:

Changing the Op Amps won't boost the bass.

that depends on the cct and opamps in question. replacing the smd opamps from the i/v and hp stage of my matrix cube (early issue) completely revived this puppy for me. now, listening with hfi-780 and modded t50rp, there is very palpable 20hz performance & impacting bass, amongst other 'things'.

 

[jcx]

before and after frequency response plots, files? - even cheap or onboard soundcards are repeatable enough to reslove audio frequency response a few orders of magnitude below DBT audibility thresholds of ~ 0.1 dB
 
the math/engineering/pschoacoustics numbers really don't support the idea of "good", appropriate for "audio" op amps applied within their limits having subjectively significant difference in 20 Hz-20 kHz frequency response in low gain circuits like this
 
there actually is a Science to listening tests - requires level matching, Blinding

 

[purrin]

Maybe it's best we keep FR measurements and discussions DBT regarding opamps in the sound science forum. These types of topics usually result in endless meaningless circular discussions with extremists from the subjective and objective camps flinging turd all over the walls of the forum.

 

[geetarman49]

indeed!  ... but i do stand by my assessment as to the difference switching opamps made to the  my ipo matrix cube.
 

 

[jcx]

If I said "I don't hear that mod that way" - purely subjective, unsupported opinion it would be fine?
 
but mentioning engineering, psychoacoustics - things the designers of the equipment may have taken into account I'm suddenly off topic, inviting flame wars???
 
Frequency response audibility is fair game in any forum where someone claims ~ "I heard more bass/forward mids/too bright..." from X gear under Y conditions...
 
only "debating"/flaming over DBT validity is restricted to the Sound Science Forum - and most of that in my experience is "blaming the victim" - mature individuals can skip over anything that doesn't interest them
 
but censoring the fact that there are results from perceptual psychology, or that some numbers in audio do mean some distinctions can be drawn even if "numbers aren't everything" is a disservice to newcomers
 
educating people on valid listening, known interfering mechanisms should be in the serious "Subjectivist's" interest - keeping echo chamber/fanboy/wannabe glossy magazine reviewer post noise down

 

[geetarman49]

Quote:

If I said "I don't hear that mod that way" - purely subjective, unsupported opinion it would be fine?
 
...

yes, it would be fine ... one doesn't need to delve very deep into the pages of this site to see the range of opinion on hd650, k701/702, t1, ultrasone xxx, rpt-hf600, etc.  & it goes wrt modding too.
 
but we are taking this thread on the yellow brick road  (& there are a range of opinions about that movie too ... all subjective & it's okay).

 

[purrin]

I don't know if anyone has noticed, but I rather like measurements myself. I've also performed enough measurements to know that not everything can be explained by them, and that newer more advanced techniques may be required to measure phenomena not previously measurable.
 
It would be nice for me, once a while, to suggest an op-amp or two, or the class A mod, for others to consider without someone on the fringes of the objectivist religion always there to scream "snake oil", "placebo", "disservice", "perceptual psychology", etc. (This is not the first time it's happened to me in this thread.)
 
The cost to the owner to try out a few op-amps would be a few dollars, maybe twenty at most. This is hardly the domain of "fanboy" or "wannabe glossy magazine reviewer". Besides, a large portion of this thread has already been dedicated to op-amp rolling, the class A modification, and other modifications which I posted about a year ago.
 
Op-amps do measure differently on the bench in terms of current, distortion, noise, voltage swing, slew rate, bandwidth, stability, PSRR, CMRR, etc. I also find them to sound different, despite all of them having perfect frequency response. This I speak from personal experience building simple amps and messing with stuff, not conjecture.
 
To each his own. 

 

[Currawong]

 

[rhythmdevils]

Love the picture Currawong! 
 
I have nothing meaningful to add to this discussion. 

 

[dogwan]

Quote:

 
I just got chills.....why?
 
Ohhhhhh!
 

 

[geetarman49]

Quote:

I don't know if anyone has noticed, but I rather like measurements myself. I've also performed enough measurements to know that not everything can be explained by them, and that newer more advanced techniques may be required to measure phenomena not previously measurable.  agree, measurements can be very helpful
 
It would be nice for me, once a while, to suggest an op-amp or two, or the class A mod, for others to consider without someone on the fringes of the objectivist religion always there to scream "snake oil", "placebo", "disservice", "perceptual psychology", etc. (This is not the first time it's happened to me in this thread.)  agree
 
The cost to the owner to try out a few op-amps would be a few dollars, maybe twenty at most. This is hardly the domain of "fanboy" or "wannabe glossy magazine reviewer". Besides, a large portion of this thread has already been dedicated to op-amp rolling, the class A modification, and other modifications which I posted about a year ago.  agree
 
Op-amps do measure differently on the bench in terms of current, distortion, noise, voltage swing, slew rate, bandwidth, stability, PSRR, CMRR, etc. I also find them to sound different, despite all of them having perfect frequency response. This I speak from personal experience building simple amps and messing with stuff, not conjecture.  agree
 
To each his own.  amen to that ... & back to the matrix.

 

[Chris J]

I don't know if anyone has noticed, but I rather like measurements myself. I've also performed enough measurements to know that not everything can be explained by them, and that newer more advanced techniques may be required to measure phenomena not previously measurable.

It would be nice for me, once a while, to suggest an op-amp or two, or the class A mod, for others to consider without someone on the fringes of the objectivist religion always there to scream "snake oil", "placebo", "disservice", "perceptual psychology", etc. (This is not the first time it's happened to me in this thread.)

The cost to the owner to try out a few op-amps would be a few dollars, maybe twenty at most. This is hardly the domain of "fanboy" or "wannabe glossy magazine reviewer". Besides, a large portion of this thread has already been dedicated to op-amp rolling, the class A modification, and other modifications which I posted about a year ago.

Op-amps do measure differently on the bench in terms of current, distortion, noise, voltage swing, slew rate, bandwidth, stability, PSRR, CMRR, etc. I also find them to sound different, despite all of them having perfect frequency response. This I speak from personal experience building simple amps and messing with stuff, not conjecture.

To each his own. 

My thoughts on your first paragraph:
"we don't know what we don't know"

As far as I'm concerned, changing the Op Amp in the M is a worthwhile endeavour.
Just don't expect a miracle, the M will still sound like an M Stage.

But you raise a few good points:
for a few dollars why not roll in different Op Amps? Have some FUN!

 

[Mad Max]

Quote:

Changing the Op Amps won't boost the bass.

 
If you add AD797BR chips soldered to single DIP adapters then inserted to a socketed 2x1 DIP adapter, you'll get a LPF in the feedback and get a little more bass, LOL!
At the cost of additional degradation of sound quality.  =\