[USAudio]

I've been researching balanced headphone amplifiers to be fed by my Lavry DA11.  Headphones will be either the HD800's or LCD-2's.  I would only be using it as a stationary desktop amplifier.
 
So far I've only been looking at full-size amplifiers as I have no need for a portable amplifier.  However, after reading about the new SR-71B on the RSA website and the various reviews here, it appears the SR-71B offers performance that is comparable to and often superior to other full-size balanced headphone amplifiers, at any price. 
On the RSA website it even states:
"This makes SR-71B as compatible to the best of home base amps if not better. "  (Note: I'm assuming he meant "comparable" to, not "compatible to")
 
Given that, I have a few questions:
 
1) Other manufactures, such as Red Wine Audio, feel that operating off battery power offers the best performance.  Does the SR-71B only draw power from the batteries or if the batteries are depleted, will it still function if plugged into the AC adapter?  Can I just leave the SR-71B plugged into it's charger all the time?
 
2) Is the balanced plug for the SR-71B only available in a right-angle configuration, or are there plugs available that plug straight in like a typical XLR or RCA plug would?  As I said above, I would use the SR-71B as a desktop amplifier only and have no need for the space savings a right-angle plug offers, and would thus prefer a straight plug instead.
 
3) On the RSA website ( http://www.raysamuelsaudio.com ) it also states:
"There is nothing out there to even come close to what the SR-71B can offer. The state of the art fully differential input to output with best audio specs ever when it comes to low noise, bandwidth, slew rate & dynamics. "
I can't seem to find published specs for the SR-71B to corroborate this -- does anyone have a link to the SR-71B's specifications?
 
4) Any supporting or opposing feedback on the above assertion that the "SR-71B offers performance that is comparable to and often superior to other full-size balanced headphone amplifiers, at any price", is appreciated. 
 
5) For fun, has anyone compared the SR-71B's balanced output SQ to that of RSA's "The Apache" balanced headphone output?
 
Thanks!

 

[USAudio]

Added question #5.

 

[wolfen68]

 
Quote:

1) Other manufactures, such as Red Wine Audio, feel that operating off battery power offers the best performance.  Does the SR-71B only draw power from the batteries or if the batteries are depleted, will it still function if plugged into the AC adapter?  Can I just leave the SR-71B plugged into it's charger all the time?
 
2) Is the balanced plug for the SR-71B only available in a right-angle configuration, or are there plugs available that plug straight in like a typical XLR or RCA plug would?  As I said above, I would use the SR-71B as a desktop amplifier only and have no need for the space savings a right-angle plug offers, and would thus prefer a straight plug instead.
 
3) On the RSA website ( http://www.raysamuelsaudio.com ) it also states:
"There is nothing out there to even come close to what the SR-71B can offer. The state of the art fully differential input to output with best audio specs ever when it comes to low noise, bandwidth, slew rate & dynamics. "
I can't seem to find published specs for the SR-71B to corroborate this -- does anyone have a link to the SR-71B's specifications?
 
4) Any supporting or opposing feedback on the above assertion that the "SR-71B offers performance that is comparable to and often superior to other full-size balanced headphone amplifiers, at any price", is appreciated. 
 
5) For fun, has anyone compared the SR-71B's balanced output SQ to that of RSA's "The Apache" balanced headphone output?
 
Thanks!

1.  The SR71b will function off of AC.  I believe but am not sure that it can be left plugged in all the time.  I've been curious if the unit will still work off AC if the battery is dead (not as in charge but at end of lifespan).
 
2.  The plug is only available as a right angle, however there has been some DIY modifications here to make a straight plug.
 
3.  I haven't seen any specs yet.
 
4.  While the b is very nice, I would be surprised if anyone at Head-fi recommended it to you over potentially cheaper desktop options given the circumstances of use you describe. 
 
5.  Can't help here...I haven't heard an Apache for 2-3 years. 

 

[USAudio]

Thanks Wolfen.
 
Quote:

... 4.  While the b is very nice, I would be surprised if anyone at Head-fi recommended it to you over potentially cheaper desktop options given the circumstances of use you describe. 
...

If someone can recommend a less-expensive balanced headphone amplifier that offers the power to easily drive headphones such as the LCD-2 like the SR-71B does, and with comparable SQ, please let me know!

 

[Jalo]

Well, the Ibasso Toucan can offer balance in and balance out at cheaper price and still can drive the LCD2.
The Protector can give you single ended input and balance output also at lower cost and can still drive the LCD2.

 

[USAudio]

So I guess the bottom line is that even though the SR-71B is positioned by RSA as being competitive with any balanced amp out there (portable OR full-size) the consensus here is that it is a good portable but not quite competitive with other full-size balanced offerings.

 

[Severanth]

USAudio I don't think that is the consensus.  Skylab's SR-71B review found on this forum support that it is just as good some and better than other desktop equivalents.
 
I would hazard to say the product is too new to tell, where it sits in the balanced desktop amp league so to speak.  
 
Once it has been played with at a few meets and compared with a variety of amps and ears there can be a better consensus.

 

[USAudio]

Thanks Severanth.
 
Quote:

... it is just as good some and better than other desktop equivalents. ...

 
This is what I am hoping to be the case!
 

 

[dj nellie]

I have the Lavry DA-10 and the 71b.  So far, it seems that there's something off when I run the 71b in fully-balanced mode with the DA-10; because the volume is adjustable on both the DA-10 and the 71b, it feels and sounds a bit like amping the headphone out of a DAP.  I have to turn the 71b's volume almost all the way down to eliminate hiss/distortion, and the sound is a bit more distant and slightly duller with my Edition 8 (with Protector plug) than just using the DA-10's headphone amp (with a stereo plug adapter).
 
My guess is that the DA-10's balanced output was meant to feed higher-end preamps and amps, mostly for stereo use.  There may be some explanation for this based on the output impedance of the XLR outputs and the 71b, but I'm not going to pretend that I understand all that.  Bottom line:  The 71b is incredible with just about every other source I have, especially the HiFiMAN HM-801 and my WhipMod, both of which have a true line-out.  But the 71b's lack of synergy with the DA-10 has me searching for a reasonably-priced SE amp.  If you're planning on using the DA-11 as your exclusive source, then you may want to consider a balanced desktop amp, although I'm not aware of one that's less than $1000 (most are $1700+), and I'm not sure that the DA10/11's balanced outputs will sound good with any balanced headphone amp.

 

[USAudio]

Quote:

I have the Lavry DA-10 and the 71b.  So far, it seems that there's something off when I run the 71b in fully-balanced mode with the DA-10; because the volume is adjustable on both the DA-10 and the 71b, it feels and sounds a bit like amping the headphone out of a DAP.  I have to turn the 71b's volume almost all the way down to eliminate hiss/distortion, and the sound is a bit more distant and slightly duller with my Edition 8 (with Protector plug) than just using the DA-10's headphone amp (with a stereo plug adapter).
 
My guess is that the DA-10's balanced output was meant to feed higher-end preamps and amps, mostly for stereo use.  There may be some explanation for this based on the output impedance of the XLR outputs and the 71b, but I'm not going to pretend that I understand all that.  Bottom line:  The 71b is incredible with just about every other source I have, especially the HiFiMAN HM-801 and my WhipMod, both of which have a true line-out.  But the 71b's lack of synergy with the DA-10 has me searching for a reasonably-priced SE amp.  If you're planning on using the DA-11 as your exclusive source, then you may want to consider a balanced desktop amp, although I'm not aware of one that's less than $1000 (most are $1700+), and I'm not sure that the DA10/11's balanced outputs will sound good with any balanced headphone amp.

Hello,
I have the Lavry DA11 and as it's used by both consumers as well as professionals, the DA11 manual there are some very specific instructions on connecting the XLR outputs, adjusting the output level appropriately, etc. 
If you haven't already, you might consult your DA10 manual.
Also, the Lavry forum is a great place to research and post these kinds of questions:
http://www.lavryengineering.com/lavry_forum/
 

 

[dj nellie]

Thanks for the suggestion.  I have read the manual, and I just don't see what (if anything) I'm doing wrong.  The DA10's jumpers are on default (balanced), and I'm in Crystal mode (I might try Narrow to see if that helps).  I'm using a simple XLR to Protector plug cable to go to the 71b. 
 
I think the DA10's XLR outputs don't mute the internal volume control, and that seems to degrade the signal b/c you have 2 simultaneous volume controls.  I don't know what the technical explanation for this is, but I know it doesn't sound as clear, forward, and vivid as a true line-out or even the DA10's headphone amp.  Kind of makes me scared to plunk down $1700 for a true desktop balanced amp.

 

[USAudio]

Quote:

... I think the DA10's XLR outputs don't mute the internal volume control...

It doesn't.  You might check out the DA11's manual on page 14 and see if that helps, it might be more detailed than the DA10 manual:
http://www.lavryengineering.com/white_papers/DA11_Manual.pdf
Or alternatively email Lavry support.  Brad there is very responsive and knowledgeable.

 

[USAudio]

dj nellie,
I saw your thread at the Lavry Engineering forum, were they able to resolve your issue with the DA10/SR-71B ???