I prefer to use connection scheme number 2 above, this conforms with AES guidelines for wiring "balanced" connections, and I wire all my components this way. Keep the pin 1 to chassis connection as short as possible. I run a short wire from ground of the Mercury to the chassis, and make sure that all chassis panels are electrically continuous, which may require removing some anodizing or paint. Essentially this scheme assumes that your XLR cable is wired "correctly", that is with a twisted pair (or perhaps quad) for pins 2, and 3, and that pin 1 is connected to a full coverage braided shield, ideally with no drain wire. Here is a great paper on grounding, differential signaling, and balanced connections from Bruno Putzeys
Thanks alot Barrows, this is exactly what I was looking for.
I hooked up my XLR cables a while ago. I used Mogami 2534, and believe I combined 2x clear to pin (2), 2x blue to pin (3), and shield to pin (1).
Sounds good! (sic) That Mogami cable is quad star with is worth the extra in my experience, although I prefer the Canare equivalent. As well as the excellent article by Bruno Butzeys that Barrows pointed you to, there's an excellent article on the Rane site on the Pin 1 Problem, and an equally excellent article on the Linear Audio site about how the pin 1 to chassis fix has corner cases that still allow problems. In practice, I have found the advice in the Race article to work in all cases so far.
I'm having trouble finding u.fl cables on mouser to connect the digital sections. I need 4 right angle female cables on both sides correct? Can someone share a mouser part number if they have one
I used Mouser # 798-U.FL2LP04N1A100
Thanks, so they work ok? They're just under 4 inchesI used Mouser # 798-U.FL2LP04N1A100
Thanks, so they work ok? They're just under 4 inches
Haven't had any problems
Thanks, so they work ok? They're just under 4 inches
If you want shorter ones, I used these:
Linx Technologies Plug (Female) Plug (Female) RF Cable Assemblies | Mouser
They come in 100,200,300mm
(they are also way cheaper)
I don't have access to an AP (they cost about $30K) - but ESS measured the IVY circuit + ES9018(B32 in this case) for us. B-II,III etc are all using the same DAC (ES9018).
-117db THD+N and ~129db DNR(stereo)
That output stage was identical in function to the IVY-III. Mercury is also very similar.
I have measured (on PC using sound cards) all of my modules - but those measurements are limited by the capability of the sound card ADC etc. I don't consider them very accurate - just a sanity check.
Also note that for any balanced output DAC you need a fully differential ADC on the test instrument in order to measure it accurately. The balanced output will always be superior to the SE output - but measuring differential signals by the difference of 2 SE channels is not ideal - because single ended each channel will have its own errors. That's why I would love to have an AP. If anyone wants to donate one let me know.
I recently stumbled upon the site audiosciencereview.com
One of its main attractions is when the user and founder of the forum: amirm dissects gear with his AP. He gets his hands on hardware via all kinds of sources (purchase or lending from other forum members/manufacturers). He does measurements with no candy coating, and it's absolutely beautiful to watch. There's been some interest i seeing how a Buffalo III stacks up compared to the commercial outings. If you lend him a reference Buffalo-IIIsePro build, I'm sure he'll gladly do any measurements you'd ask for
I'm going to do a build myself at some point, and I wouldn't mind lending it to him, but i'm not sure it would be the best representation
I saw those first but wasn't sure if there were shorter ones. I think I'll try thoseIf you want shorter ones, I used these:
Linx Technologies Plug (Female) Plug (Female) RF Cable Assemblies | Mouser
They come in 100,200,300mm
(they are also way cheaper)
I saw those first but wasn't sure if there were shorter ones. I think I'll try those
Is there any concern using u.fl cables that are not especially short, something like 100-300mm ?
maybe...
I have been advised by people who should know, that keeping them 100mm or less is "best". Longer does "work" though...
Is there any concern using u.fl cables that are not especially short, something like 100-300mm ?
I have been advised by people who should know, that keeping them 100mm or less is "best". Longer does "work" though...
There is no magic length. I2S lines are high-frequency clocks, and have potential to both generate a lot of radiated noise, and pick up interference that muddies the clock signals. Keeping them as short as possible is the key. Shielded u.fl cables can help curb those problems, but the "short as possible" rule still applies.
Concerning u.fl cables, I was just recently able to finally eliminate a high pitched distorsion that I had in the background when playing DSD through the Buffalo.
I was using the shortest u.fl cables I could (40 and 70 mm), but their diameter was only 0.81 mm. The distortion was gone after I changed them for 1.37 mm diameter cables. I suspect it was mostly the MCLK cables that needed to be thicker (using 90.3168 MHz clock).
I was using the shortest u.fl cables I could (40 and 70 mm), but their diameter was only 0.81 mm. The distortion was gone after I changed them for 1.37 mm diameter cables. I suspect it was mostly the MCLK cables that needed to be thicker (using 90.3168 MHz clock).
Last edited:
I have a question that does not seem to have an existing answer on the interwebs.
Why bother converting both phases of a dac to SE when the use case is for SE only?
It seems to be standard practice to do so even if balanced will not be used.
The only reason I can think of is for common mode distortion cancellation from within the dac itself but most dacs are not internally matched enough to take advantage of this and even if they were, is common mode dac distortion even audible?
Why bother converting both phases of a dac to SE when the use case is for SE only?
It seems to be standard practice to do so even if balanced will not be used.
The only reason I can think of is for common mode distortion cancellation from within the dac itself but most dacs are not internally matched enough to take advantage of this and even if they were, is common mode dac distortion even audible?
Hey guys - I have not had much time to play with pure-sync until this weekend. I am working on it today and have a few observations:
Importantly - we must set a clock gearing ratio to play DSD (and to get optimal PCM). The gear ratio will entirely depend on the frequency of your master clock. The key is you need to gear the clock to 128FS. This has some implications for hermes/cronus.
The key here is we need to use some port expander positions to indicate what gearing to use. This could be automated from certain sources like the amanero - but not (currently - at least ideally) via hermes/cronus because you would lose isolation. So the best short term solution would be to set the gearing manually (via the DIP/Panel switches or controller) and then stick to a single sample rate - possibly resample all content at the player.
Open to suggestions
Importantly - we must set a clock gearing ratio to play DSD (and to get optimal PCM). The gear ratio will entirely depend on the frequency of your master clock. The key is you need to gear the clock to 128FS. This has some implications for hermes/cronus.
The key here is we need to use some port expander positions to indicate what gearing to use. This could be automated from certain sources like the amanero - but not (currently - at least ideally) via hermes/cronus because you would lose isolation. So the best short term solution would be to set the gearing manually (via the DIP/Panel switches or controller) and then stick to a single sample rate - possibly resample all content at the player.
Open to suggestions
- Home
- More Vendors...
- Twisted Pear
- Introducing the Buffalo III-SE-Pro 9028/9038