[cssarrow]

Hello,
 
I'm checking back here.
 
Ryan was selling the Burr Brown OPA627AU's for $45 which is outrageously expensive so i was able to get three on ebay for $22.50
 
Pop'd them in and the sound exceeded that of the OPA2604. It was a somewhat clearer, more detailed, and less grainy than the one before. The OPA627 is much better.
 
http://www.ebay.com/itm/1-Pieces-Dual-to-Mono-OPA627AU-OPA627-FREE-SHIPPING-/120763718688?pt=LH_DefaultDomain_0&hash=item1c1e141c20
 
the op amps were running a little warm so i put some aluminum heatsinks on  them, also added a 80mm below and above the sound card for good air flow cooling.

Datasheet says they can go up to 125C, but i did it just in case.
 
Now going to buy the LM4562 Op Amp which people say beats the OPA627 in term of sound quality and see if this is true when applied on the Maverick D2. I will re-listen to all three again (OPA2604,2x OPA627AU SOIC,LM4562) and let know what i think.

 

[open_air]

I have to say I wasn't as happy with the sound of my D2 as most others seem to be.  I found myself getting bored or irritated after listening for an hour or so.  I've given mine away to a friend.  Back to good old reliable vinyl.  Oh, well.

 

[apollo7157]

I am looking to upgrade my Mav-audio TubeMagic D1. I am a new user to this forum but I was hoping someone might be able to make some general recommendations for the best all-around upgrades I can do. I realize this is the forum for the D2 but the D1 thread is pretty dead these days so I'm reposting here.
 
Anyways, I figure I can probably get more bang for my buck by upgrading the OpAmps rather than upgrading to the D2, especially since I'm already quite happy with the D1. I've found that the highs are somewhat too shrill for my taste and the lows are too bloated and loud when using the optical out from an auztentech prelude, and connecting krk active monitors + krk sub directly to the D1. I've browsed through many pages of the D1 thread but I can't possibly read through all of it, so perhaps someone who knows could summarize, or perhaps link me to a page in that thread that does - the front page "condensed" thread doesn't really identify the "best" upgrade, though I suppose there is a degree of personal preference involved here. 
 
They are now selling the OPA 627 mod on the mav-audio site, and according to an email exchange I had with their tech support, Ryan, he suggested that their testing indicated this was the "best upgrade." What do you think? I've seen many posts suggesting that this Sun HDAM thing may be a better upgrade, and I went through a few posts that talked about the "skyline" mod. I would be up for doing the mod myself I think...though the audio-gd website is a total disaster and it's not clear how to order one.

 

[cssarrow]

@ Apollo7157
 
$45 for 3 dual sided SOIC OPA627 is pretty expensive.
 
I got mine for $7 each, total of $21 with free shipping on ebay.
 
You only need two, so even cheaper for you.
 
This is where i bought it: http://www.ebay.com/itm/120763718688?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
 


 

 

 
Paired with Audioengine A5's.

 

[_Spanky_]

cssarrow, is there a noticeable improvement in quality? At that price, I would be concerned that they're fake. Ryan's seem to barely generate any profit because the chips themselves are so expensive. If the OPA627 were $7 for 2, meaning $3.50 each, they would be used a lot more but I think they're upwards past $8 a piece though.

 

[cssarrow]

Hello,

 
I noticed the improvements within the first few seconds.
 
Here are the improvements i noticed between OPA627 vs OPA2604
 
OPA627 (9.5/10)         vs                                   OPA2604  (6/10)
-------------                                                          -----------------
+Detail                                                             - Grainy detail
+Sounds Fuller                                                 - Sound isn't well rounded, kind of like an arrow
+Well Toned Transitions                                    - Seperate sounds aren't well outlined
+Punchier Sharp Bass                                      + Not far in terms of punchyness than the OPA627
+No Blending Sounds/Syrupy Sound                  - Sound is too blended,muffed,syrupy
 
Better built discrete boards would be 10/10 in my opinion.
That's all my opinion of course. Pretty sure i wouldn't notice that many differences if i had gotten fake op amps.
if they were $8 a piece for OPA627 SOIC it would be $48 + shipping, which means he would suffer a loss. So he must get them way cheaper than that.
 
Next step for me is to fix this static issue in my Audioengine A5's Tweeter. Nothing connected, and it still has static. Must be the Power cable.

 

[apollo7157]

I ordered a few from the ebay source that cssarrow suggested so I'll post here when they arrive and let you know how they sound.. I think I'm going to test them out and depending on the result think about the SUN HDAM. 

 

[cssarrow]

Hey Spanky,
 
I got a real quick question. Since you're most likely more experienced than me in the audiophile world and we both have Maverick D2's, my question is,
 
Do you recommend me get a Maverick A1 Hybrid to pair with the D2?
 
Currently my D2 has OPA627's, and i only use the Solid State Out because i do not like the tube sound from the vacuum tubes.
The speakers i use for the DAC is Audioengine A5 which are powered speakers with built in amp, so i was thinking i wouldn't need the A1 to drive it nor amplify it.
 
However, now that I bought my 2nd pair of headphones, the Ultrasone HFI-2400 to replace the old Sennheiser HD 598, i wonder if i should get myself an amp since the ohm is a lot higher on the newer headphones.
 
It kind of feels strange for me to spend $200+ just to amplify a 70ohm headphones.
The A1 goes through the tube before going through the solid state i hear, which makes me even more skeptical. (because dislike tubes)
 
So having said that, do you think it would benefit me, or am i better off getting a smaller amplifier from FIIO.
 
Let me know
 
- Tim

 

[_Spanky_]

70ohm isn't much. What are you using for amplifying now? Getting something that amplifies with a decent amount of power, unlike motherboard audio will make a difference. I don't think it's worth justifying $200 in the A1, although it does have a nice sound. Even a cheap CMOY/Penguin amp will do you good.

 

[cssarrow]

Well as of now i have my PC connected to the Maverick D2 DAC via USB. 24bit/96Khz
 
Playstation 3 connects to DAC via Optical. (rarely used)
 
RCA to 3.5mm male connecting the Solid State on the Maverick D2 DAC to the Audioegine A5 Active Speakers
 
When i use my headphones, i have an RCA to 3.5mm female connecting the Tube Pre-Out to my headphones.
 
If i got the A1 i think it would be meaningless to run it from the D2 > A1 > Audioengine A5 right? Since two ampliers will just create more noise.
That said, it seems the A1 would only benefit me by amping my headphones a little. So it's kind of a waste of money right?
 
So do you recommend any Desktop Amps mainly for headphones?
 
D2 DAC > Audioengine A5
D2 DAC > Desktop Headphone Amp > Ultrasone HFI-2400
 
Is what im looking for.

 

[_Spanky_]

WOAH, don't use the tube output with headphones! Very bad! It has a possibility of burning them up! Get an amp, even if it's a cheapie tube or cmoy amp off of eBay.
 
For the A5's, no need to use the A1 unless you want to play with tube sound. THD would probably go up as well.

 

[cssarrow]

:{ i had no idea that it was bad to do that. I thought that both outputs can go to anything including headphones.

May i ask, why is there a possibility of burning them? Does the tube out provide too much current?

Also, a cheapie tube|cmoy amp won't affect the sound quality from the D2 going into the headphones right?

For me now, would going for a more expensive headphone amp over the cmoy be beneficiary to the sound that the headphones deliver at all?

 

[_Spanky_]

It's in the D1 thread:
 
 
Quote:

[size=large]Do's and Don'ts[/size][size=large]:[/size]

Spoiler

1. Do not attempt to connect headphones directly to the "Tube Pre Out" connections on the back of the unit. Several users report the output being electrically hot and would require hardware such as a dedicated amplifier before connecting headphones.
   Quote:
   
   

   Originally Posted by hodgjy /img/forum/go_quote.gif Most hi-end gear sends a line-level output of 2.0v, and is the norm in Europe. In the U.S.A, a lot of mid and low end gear send a line-level output of ~0.5v. 2.0v is still within specs of most gear. When I measured the output of the D1, using a combo if the "direct button" and then maxing out the volume pot, I got these measurements: Tube pre-out in direct mode maxes out at 2.2v. Using the volume pot, 3:00 maxes out at 2.2v as well. Non-tube out is slightly cooler. It still maxes out above 2.0v, but doesn't hit the 2.2v as often as the tube pre-out.

   
   

 
Not good It's the voltage and current that's not good for headphones. As far as an amp affecting the quality of your headphones, of course it will. Any time you add circuitry, it will affect the quality. The question is, will it be noticeable with your headphones? The RCA output isn't really a headphone amp so getting a proper amp, even a cheap one (again, a cheap one is likely way better than a motherboard output) it will be a fair bit better. Of course, a $400 vs $40 will have some differences but it all depends on the quality of the headphones. No sense buying a $400 amp if you have Walmart headphones.

 

[cssarrow]

In that case, i'll stop using the rca output

I'm a little new to audiophile gear so it was a clumsy mistake.

Since my cans are about $250 i'll just buy an amp around the same price range so there are no bottle necks.
Hopefully i can find a high quality class a/b amp without tube sound.

Thanks again, you saved my cheaper headphones !

 

[_Spanky_]

Yea, with $250 cans you don't want to ruin those. See if you can find a discrete headphone amplifier (one without opamps).