[pugs]

I want a DAC that has great bass, rich holographic, smooth sound that has no sharpness to it.  Detail is not as important as a big soundstage, good imaging and impact.  I want non fatiguing highs.

You're describing the Zhaolu 2.0 dac, $109 + ($50-70 airshipping, depending where you are), save for the fact that when the brass section is sharp, it WILL be sharp... and that you don't have to give up resolution to get the characteristics you desire. Tianguis (Larry) was kind enough to turn me on to this outstanding product.

Now for the caveats -

1. I bought mine from Eddie in HK, and I realize there is a recalcitrance to deal with foreign purchases. All I can say is that Eddie offers his own warranty, and when I experienced an intermittent fault, he takes care of it, and paid for the Global Express shipping both ways for repair.
http://www.diykits.com.hk/zhaolu.html

2. The standard headphone/pre amp board included is best used as a doorstop. I've the $36 discrete upgrade headphone/preamp board on order, but haven't gotten it yet and therefore can't opine.

3. You've got to mod it to get the proper sound out of it. The 3 opamps that you must replace are socketed so its really not difficult. You simply replace the 3 outstandingly mediocre but adequate OPA2604 opamps with 3 OPA2107 opamps. While Eddie also offers a $55 capacitor upgrade (I've heard both versions) with Blackgates and Oscons, the benefit is slight in comparison to the opamp upgrade.

So for less than $200 all-in, you get engaging musical involvement and resolution, not HI-FI.

FWIW,
Paul

Do you have the A-1852 or CS-4398 DAC chip?  Is it easy to change out the opamps?  Is it a kit or does it come fully assembled?

[pugs]

If you are trying to use the Behringer to do room correction, there is a better and cheaper way.  I assume you have a mic, mic pre and software to measure?  If not there is free software you can download and the other two aren't too expensive.

Once you have measured your room, you'll need to look for the software (free, part of speaker workshop, iirc, check out the freq-something consortium) that works out the convolution you need to perform and then there is a thread on slim device's forum about how to add the convolution to your slim server, so that your computer does the room correction on the fly for you and then you don't have to worry with all the extra hardware.

Basically, it isn't as hard as it sounds, you just need to look up the various pieces as I haven't done it personally (own a DEQX).  

Wow... how didn't I know about this!  This sounds like a very elegant, yet powerful, solution.
Josh would you elaborate a bit more for the newbies out there....me too!

Can you recommend a mic and mic pre-amp?  How is the mic pre-amp connected to a PC in order to save the correction curve?
Does this approach have any limitations for frequency/room correction?
 
Sorry for the dumb questions.

EP

I am definately interested in this also.  I read more about it on the Slim Devices forum and it doesn't look like the software is quite ready yet.

[windwaves]

Scott Nixon Tube DAC!

USBTD is a best bet for MAC and PC users.

http://www.scott-nixon.com/dac.htm

wow !  100% agreed.
I tested for days the USBTD, the Benchmark and the Lavry and found the USBTD undoubtly superior.  And it is half the price.

[Occam]

Do you have the A-1852 or CS-4398 DAC chip?  Is it easy to change out the opamps?  Is it a kit or does it come fully assembled?

Fully assembled, its fully operational and ready to go when you receive it. My version is the standard AD1852 version dac. I just ordered the  $62 CS4398 dac, but have not received it yet. Frankly, because of the CS4398 'warm' nature, I wouldn't think it a particularly good fit with my favorite opamps, those opa2107s; it would be too warm and cuddly for my tastes. Nor did I find the popular mod of removing the dac to output coupling caps particularly copacetic, very hi-fi but not musical. Though the CS4398 might be a good fit for removing the coupling caps and using a discrete output stage ala ultranalog
http://ultranalog.com/cdenhancer/sacdenhancer/page2.html
or some of the popular variations of it.

But frankly, from the description of what you're looking for, the bog standard version of the Zhaolu 2.0 should be exactly what you're looking for. All you'd need to do is pull those 3 wretched OPA2604s from their dip8 sockets and replace them OPA2107s. No soldering, no muss, no fuss. If you're in the NYC area, I'll do it for you. The 2107 is a bit spendy in the world of opamps @$12ea (cheaper on Ebay), but well worth it, as they do everything (for this application) mo betta than the opa2604.

If you decide to go for room correction on your computer and use the Vinnie modded SB3 for dac duties, have Vinnie replace your SB3's OPA2604 with the OPA2107.

Regards,
Paul

[JoshK]

Wow... how didn't I know about this!  This sounds like a very elegant, yet powerful, solution.
Josh would you elaborate a bit more for the newbies out there....me too!

Can you recommend a mic and mic pre-amp?  How is the mic pre-amp connected to a PC in order to save the correction curve?
Does this approach have any limitations for frequency/room correction?
 
Sorry for the dumb questions.

EP

I was afriad of this question.   The reason is I haven't tried it, so I can't exactly spell out the step by step instructions other than to know if you have the requisite equipment (mic, pre, soundcard) and play with the drc or other such software, it is totally doable.  

What pugs is referring to about the software not being there is, I think more of a turn key solution, which what I wasn't referring to.  I read a thread on slim devices where a gentlemen did some code that when added to the slim devices source file would do the convolution for you, provided you have worked out that math (via software).  I think it may have been on the linux forum over there.  

I read enough to at that point have felt that I could have done it given the time to invest in playing around with the measurement software, which I haven't yet.   Basically my post was more to inspire that the research and work wouldn't be fruitless, that it could be done, but I wasn't writing the manual, if that makes sense.

Maybe if I can get some time this fall (my summer is hopeless) I can have a go at it and try to write a tutorial on how its done.  

[JoshK]

Take a look at this thread over at SD's forum.  It was what I was referring to.  The second to last post looks like someone actually did it, so you may have to look to see how they did it.  You will likely have to do some reading on the subject so you gain a handle on what is going on and what you need to do. 

Of course, all of this hinges on whether you can make good measurements and know how to measure.  Take a look at some of the wiki's mentioned in the thread and they should yield many invaluable resources on getting up to speed on that end.

[Gordy]

Thank you for re-posting the Zhaolu Paul!  Do you still have the link for the US agent? 

[Occam]

Hey Gordy,

The Stateside vendor of the Zhaolu is -
http://www.ifiaudio.com/d2.html
and as their price include UPS shipping, they're about the same as dealing with Eddie in Hong Kong.

Correction - I'd said that I'd ordered the discrete headphone/pre amp upgrade board... well, the USPS tracking said Eddie received it today, so I emailed him asking him to include that upgrade board and I'd ppal him the needed funds. Too late. He'd received my Global Express package (on his nickle), and airmailed me a new board and the additional DAC board within a few hours. Talk about fast service. I'd previously had reservations about buying directly from China, but in the case of Eddie, I now have no reservations. His English isn't that good, but hey, my Chinese is MIA. Besides, even if you don't buy his $55 capacitor upgrade with the Blackgates and Oscons, he upgrades the ps and coupling caps with Elnas gratis, hence he provides his own (very excellent) warranty service.

This isn't to say that ifiAudio (an unfortunate choice of name) isn't also stand-up, but I've not dealt with them.

as ever,
Paul

[gitarretyp]

I've not heard it personally, but the storm digital do2 has gotten some really good reviews over at head-fi; however, it's a little above your price range (~500 shipped). (I'm also curious about this dac if anyone has heard it and compared it to other dacs).

[JoshK]

I need a DAC for my HT system (2ch)...I think I might have to pick up one of those Zhalou's.  Paul, you mean to tell me you haven't implemented Gary's instrumentation opamp output yet? 

[Occam]

Hey Josh - Actually, SWMBO has laid down the law, no building, just minor tweaking until I spend some time pursuing my vocation, rather than my avocation. For some odd reason she wants mo money. What pisses me off is that she is right....
Gary's instrumentation amp output stage would actually be ideal for implementing on the Zhaolu. Its architecture is ideal for it, balanced voltage outputs from the dac. And iff'n you want balanced outputs, you could extend Gary's work and use a THS4131 instead of the INA103, which would give a wonderfully balanced [TI finally liscensed Nelson Pass SuperSymmetry(tm) patent] outputs.

To be honest, Gary's instrumentation amp output stage DI/O was one of the cleanest and most accurate DACs I've ever heard. Actually, its too clean for my preferences. I actually want a bit of 2nd and 3rd harmonics.

[Harmon]

I want a DAC that has great bass, rich holographic, smooth sound that has no sharpness to it.  Detail is not as important as a big soundstage, good imaging and impact.  I want non fatiguing highs.

You're describing the Zhaolu 2.0 dac, $109 + ($50-70 airshipping, depending where you are), save for the fact that when the brass section is sharp, it WILL be sharp... and that you don't have to give up resolution to get the characteristics you desire. Tianguis (Larry) was kind enough to turn me on to this outstanding product.

Now for the caveats -

1. I bought mine from Eddie in HK, and I realize there is a recalcitrance to deal with foreign purchases. All I can say is that Eddie offers his own warranty, and when I experienced an intermittent fault, he takes care of it, and paid for the Global Express shipping both ways for repair.
http://www.diykits.com.hk/zhaolu.html

2. The standard headphone/pre amp board included is best used as a doorstop. I've the $36 discrete upgrade headphone/preamp board on order, but haven't gotten it yet and therefore can't opine.

3. You've got to mod it to get the proper sound out of it. The 3 opamps that you must replace are socketed so its really not difficult. You simply replace the 3 outstandingly mediocre but adequate OPA2604 opamps with 3 OPA2107 opamps. While Eddie also offers a $55 capacitor upgrade (I've heard both versions) with Blackgates and Oscons, the benefit is slight in comparison to the opamp upgrade.

So for less than $200 all-in, you get engaging musical involvement and resolution, not HI-FI.

FWIW,
Paul

Hey Occam. Where can I purchase the 3 OPA2107 opamps?  Is it as simple as unplugging the 3 OPA2604 opamps and plugging in the 3 OPA2107's?  Thanks

[pugs]

Hey Gordy,

The Stateside vendor of the Zhaolu is -
http://www.ifiaudio.com/d2.html
and as their price include UPS shipping, they're about the same as dealing with Eddie in Hong Kong.

Correction - I'd said that I'd ordered the discrete headphone/pre amp upgrade board... well, the USPS tracking said Eddie received it today, so I emailed him asking him to include that upgrade board and I'd ppal him the needed funds. Too late. He'd received my Global Express package (on his nickle), and airmailed me a new board and the additional DAC board within a few hours. Talk about fast service. I'd previously had reservations about buying directly from China, but in the case of Eddie, I now have no reservations. His English isn't that good, but hey, my Chinese is MIA. Besides, even if you don't buy his $55 capacitor upgrade with the Blackgates and Oscons, he upgrades the ps and coupling caps with Elnas gratis, hence he provides his own (very excellent) warranty service.

This isn't to say that ifiAudio (an unfortunate choice of name) isn't also stand-up, but I've not dealt with them.

as ever,
Paul

I  looked at iFiAudio and it looks like a unit with the AD 1852 chip and OPA 2604 combo is not an option.  The unit with the AD 1852 chip comes with the JRC5532 opamp.  Can the OPA2107 replace the JRC5532?

[JoshK]

I  looked at iFiAudio and it looks like a unit with the AD 1852 chip and OPA 2604 combo is not an option.  The unit with the AD 1852 chip comes with the JRC5532 opamp.  Can the OPA2107 replace the JRC5532?

Since the circuit is the same, I'll presume yes.  The 1852 is the DAC so it isn't so self-rolleable (no easy sockets for plugging into like the opamps).

Which leads me to the other question asked.

Hey Occam. Where can I purchase the 3 OPA2107 opamps?  Is it as simple as unplugging the 3 OPA2604 opamps and plugging in the 3 OPA2107's?  Thanks

Probably digikey or mouser, or ebay.  Yeah it is that simple, since they have the sockets installed so opamps are 'plug'n'play'.  Don't plug them in backwards though, lest ye see fireworks! 

[ctviggen]

You can get the data sheet for the 2107 here:

http://www.datasheetcatalog.com/datasheets_pdf/O/P/A/2/OPA2107.shtml

Yeah, if you mistakenly put these in backwards, you'll be putting the -Vs onto the +Vs and vice versa. 

[Occam]

Harmon - It really doesn't matter whether you get it with a JRC5532 or an OPA2604, they're both standard DIP8 dual opamps with the same pinout, and both IMO subjectively mediocre opamps. Beyond purely technical criteria opamps really do have a subjective 'flavor'. I roughly divide them into 2 camps, the 'warm' BurrBrown sound and the 'clear as a bell' sound of AnalogDevices opamps. Among dual opamps I prefer the OPA2107, which is about as close as one can get to an OPA627 in a dual in the BB camp. In the AD camp, I prefer the AD8066, which isn't available in dip8, only smt, and is likely to go into oscillation unless the circuit is specifically designed for its very high speed. I have ordered some specific Linear Technology dual opamps which from prior experience should give that clear as a bell sound but available in DIP8 and not likely to self destruct when put into the Zhaolu.

Pugs - The version of the OPA2107 you'd want for the Zhaolu is the OPA2107AP which is the DIP8 version which you simply put in the Zhaolu's sockets after pulling whatever is in there. Sadly, Digikey, Mouser and Newark only have the SO-8 smt OPA2107AU in single quantities which would be fine if you wanted to replace the opamp in a Squeezebox. The 2107AP is only available in quantities of 50+ from these vendors. Nor does Ebay currently have any listed, though they usually do.

Awaiting the availability of OPA2107APs on Ebay or elsewhere, I'll make the following offer of 2 sets of 3 OPA2107APs for $20 delivered and Harmon and Pugs have first dibs. I just want to get the ball rolling, I'm not making any profit, and I don't want to deplete my stash. PM me if interested.

[pugs]

Harmon - It really doesn't matter whether you get it with a JRC5532 or an OPA2604, they're both standard DIP8 dual opamps with the same pinout, and both IMO subjectively mediocre opamps. Beyond purely technical criteria opamps really do have a subjective 'flavor'. I roughly divide them into 2 camps, the 'warm' BurrBrown sound and the 'clear as a bell' sound of AnalogDevices opamps. Among dual opamps I prefer the OPA2107, which is about as close as one can get to an OPA627 in a dual in the BB camp. In the AD camp, I prefer the AD8066, which isn't available in dip8, only smt, and is likely to go into oscillation unless the circuit is specifically designed for its very high speed. I have ordered some specific Linear Technology dual opamps which from prior experience should give that clear as a bell sound but available in DIP8 and not likely to self destruct when put into the Zhaolu.

Pugs - The version of the OPA2107 you'd want for the Zhaolu is the OPA2107AP which is the DIP8 version which you simply put in the Zhaolu's sockets after pulling whatever is in there. Sadly, Digikey, Mouser and Newark only have the SO-8 smt OPA2107AU in single quantities which would be fine if you wanted to replace the opamp in a Squeezebox. The 2107AP is only available in quantities of 50+ from these vendors. Nor does Ebay currently have any listed, though they usually do.

Awaiting the availability of OPA2107APs on Ebay or elsewhere, I'll make the following offer of 2 sets of 3 OPA2107APs for $20 delivered and Harmon and Pugs have first dibs. I just want to get the ball rolling, I'm not making any profit, and I don't want to deplete my stash. PM me if interested.

I will buy a set of the OPA2107APs.  I sent you a PM.

[Harmon]

Harmon - It really doesn't matter whether you get it with a JRC5532 or an OPA2604, they're both standard DIP8 dual opamps with the same pinout, and both IMO subjectively mediocre opamps. Beyond purely technical criteria opamps really do have a subjective 'flavor'. I roughly divide them into 2 camps, the 'warm' BurrBrown sound and the 'clear as a bell' sound of AnalogDevices opamps. Among dual opamps I prefer the OPA2107, which is about as close as one can get to an OPA627 in a dual in the BB camp. In the AD camp, I prefer the AD8066, which isn't available in dip8, only smt, and is likely to go into oscillation unless the circuit is specifically designed for its very high speed. I have ordered some specific Linear Technology dual opamps which from prior experience should give that clear as a bell sound but available in DIP8 and not likely to self destruct when put into the Zhaolu.

Pugs - The version of the OPA2107 you'd want for the Zhaolu is the OPA2107AP which is the DIP8 version which you simply put in the Zhaolu's sockets after pulling whatever is in there. Sadly, Digikey, Mouser and Newark only have the SO-8 smt OPA2107AU in single quantities which would be fine if you wanted to replace the opamp in a Squeezebox. The 2107AP is only available in quantities of 50+ from these vendors. Nor does Ebay currently have any listed, though they usually do.

Awaiting the availability of OPA2107APs on Ebay or elsewhere, I'll make the following offer of 2 sets of 3 OPA2107APs for $20 delivered and Harmon and Pugs have first dibs. I just want to get the ball rolling, I'm not making any profit, and I don't want to deplete my stash. PM me if interested.

I will also take a set of OPA2107APs. I just PM'ed you. Thanks

[Gordy]

Not making a profit?  More like a large loss, nice     $7.00 is the price per unit for 1000 piece lots, I paid about $40 for three 2107au's delivered a while back...

[Occam]

Yeah, well.... I got them off Ebay for about that price a while back before I (and others) started touting them and drove the price and scarcity upwards. No good deed goes unpunished.