This is strange. I switched from double speed to quad speed and replayed the two high rez samples. Couldn't really hear any difference in sound quality (although these are great recordings). I then tried using iTunes, and my stored music played just fine (even though the DAC was still set for quad speed). Does this mean that the DAC is upsampling the 44.1 quality music in iTunes. (Again, I can't "hear" any difference in the sound from double speed.)
I seem to remember some discussion of owners preferring single speed with de-emphasis for playback.
The high rez samples download to Quicktime. I wonder if that has anything to do with the sound quality.
On the optical connection, I have a first generation Mini, which does not include the built-in toslink connection. I think USB is my best bet for outputting music.
Sorry for the Mac talk. I didn't mean to drag the discussion too far off topic.
Does your Mac Mini not have an 1/8" optical connection built in to the headphone jack? I have used the optical out on my Imac and it worked very well indeed.
I have all of the parts to install my UTC A-20's and it is taking every ounce of will I have to wait! The DAC still seems to be burning in as I will leave it playing and go out for a few hours and when I come back the sound has improved. I don't think I will make it through tomorrow, however!
Please forget the optical for good sound. Optical with straight 1/8 jack is better than using a mini toslink adaptor with an optical wire but the sound is still so so. Best is using an outboard USB to coax adaptor like the Musiland.
I seriously think opening my Mac mini to use the signal before the toslink output and use a BNC jack with coax to the dac.
I'm afraid I 100% disagree with this assertion. With a decent optical cable the standard of sound reproduction can be fantastic. And I have done plenty of tests using SPDIF and optical in revealing systems. As with all technologies there are good and bad examples of both.
Using an optical cable from my (recent bought) Mac mini into this DAC I've been getting sounds to rival that from my Shigaclone -> SPDIF Cable -> same DAC. There's advantages to optical too in being galvanically isolated and also not having to worry about proper 75-ohm terminations/connectors etc.
Just my £2 worth
Using an optical cable from my (recent bought) Mac mini into this DAC I've been getting sounds to rival that from my Shigaclone -> SPDIF Cable -> same DAC. There's advantages to optical too in being galvanically isolated and also not having to worry about proper 75-ohm terminations/connectors etc.
Just my £2 worth
The first generation Mac Minis does not include the combined audio/toslink jack (unfortunately). Some months back I bought a toslink adapter for the 1/8 inch audio connection just to confirm that my Mini did not include this feature, which it didn't. Needing to connect over USB was a big part of the reason I went with the Gigawork DAC.
I'm afraid I 100% disagree with this assertion. With a decent optical cable the standard of sound reproduction can be fantastic. And I have done plenty of tests using SPDIF and optical in revealing systems. As with all technologies there are good and bad examples of both.
Using an optical cable from my (recent bought) Mac mini into this DAC I've been getting sounds to rival that from my Shigaclone -> SPDIF Cable -> same DAC. There's advantages to optical too in being galvanically isolated and also not having to worry about proper 75-ohm terminations/connectors etc.
Just my £2 worth
From computer audiophile
Problems with optical cont...
Toslink, coaxial, USB
There’s a lot to talk about which is better, more musical, dynamics…it’s only an electrical signal with an important difference.
Toslink has the advantage of no electrical connection by conduction between the source and the receiver because the medium of data is pulsed light.
The light what you see in a Toslink cable is generated by a LED at the source, and at the receiver, a device that receives light and converts the light energy to electrical signals. These devices are called optocouplers and have an inherent long term reliablity problem in that the success or failure of the device depends on how hard the LED is driven, temperature of the device and the switching response of the electrical section.
An optocoupler is far from perfect and given current commercial considerations, many devices are at their limit of operation as a normal design criteria. Whether this applies to high end DACs I would hope not, but certainly worth the question for computer sound cards and outputs. This would have a bearing on the throughput by the optocoupler at either end of the cable don’t forget. So you end up with the drama, twice, with degrading optocouplers at different rates since you have different manufacturers of optocouplers. In my line of work in industrial electronics, many optocouplers have failed in service on printed circuit boards after about ten years service. For rotating equipment, you’re lucky to get six years. Current testing for reliability is stated for 1000 hours, so you can get that time at least.
So despite isolation advantages, long term, reliable sound quality is best afforded by cabling with copper/silver/ptfe et al instead of the light. It would also explain sound quality differences from built in SPDIF light outputs from sound cards versus using USB or coaxial cables from the same computer.
References:
Google : Optocoupler Degradation
http://jase.esrgroups.org/2_3_3_08 proof.pdf
http://www.secomtel.com/UpFilesPDF/PDF/Agilent/PDF_DOCS/ISONCONT/01_OPTO...
http://vishay.ru/docs/83718/83718.pdf
Yes, I am more than familiar with what some (not all...) 'experts' say about optical, but at the end of the day I listen to the music. And I have been very impressed by the optical connection between my Mac mini and this DAC using a wide variety of music.
As always the listener is encouraged to make his/her own mind up by listening...
Measurements don't show the whole story - as always. If they did nobody would listen to valve amps now would they, just as an eample.
As always the listener is encouraged to make his/her own mind up by listening...
Measurements don't show the whole story - as always. If they did nobody would listen to valve amps now would they, just as an eample.
I didn't know anything about this theory. Many of my friends have Macs and all didn't like that optical way. Now this theory explains why.
Each to his/her own Legarem. I feel people should listen first and make their own minds up, as always. Many people on the computer audiophile forums use the optical connection on their Mac mini's. Everyone has different taste/equipment etc.
I use/like both SPDIF and optical and have heard good/bad versions of both technologies. I couldn't pick one over the other.
- J
I use/like both SPDIF and optical and have heard good/bad versions of both technologies. I couldn't pick one over the other.
- J
This is the board I ordered.
Where exactly would I attach transformers for the output. I don't see the same 4 coupling caps as in the original boards posted in the thread...
Where exactly would I attach transformers for the output. I don't see the same 4 coupling caps as in the original boards posted in the thread...
I just received the DAC. It came w/ a transformer. I'm not new to DIY, but I am new to connecting transformers and power supplies. Can someone take a look at the pic and let me know if this is how the mains wires are to be connected:
(2) 8v wires - blue ----> '9v' and '0V'
(2) 12v wires - white ---> '13V', '13V'
(1) 0 wire -- black ----> '0V' between 13Vs
(1) 110V wire -yellow ---> IEC 'N'
(1) black wire ---> IEC ? (doesnt seem connected to Line or Ground)
(1) 220V wire - red ---> (guessing this goes unused since I'm in US?)
also the black wire
Attachments
To clarify my question above. My main concern is that the IEC inlet pictured above has four prongs for attaching mains. The Yellow (110V) is attached to Neutral and the black wire I can't tell, but it's not the middle Ground lug or Line/Hot. I have not seen an IEC like this and the wiring color code is different, so before I plug anything in any thoughts would be appreciated
The 4 prong IEC inlet looks like a standard fused inlet with the yellow wire on negative and black on the positive( after the fuse). I have never worked with a transformer with 3 primaries, they usually have 2 or 4, I think that the original poster should contact the vender. If you can get a proper answer then I'd test the secondary voltages before hooking it up to the DAC.
Also being a safety freak, I wouldn't have exposed live mains sat there in the open, I'd put the IEC inlet and tranny in some sort of temporary enclosure and run the low voltage wires out from that.
Seperate transformers for the opamp bit and chips should should give the best sound.
Also being a safety freak, I wouldn't have exposed live mains sat there in the open, I'd put the IEC inlet and tranny in some sort of temporary enclosure and run the low voltage wires out from that.
Seperate transformers for the opamp bit and chips should should give the best sound.
Thanks for the reply. I figured it out. I took a second look and found the compartment w/ the fuse after seeing a similar inlet at Apexjr. The other primary is for 220V countries, so it won't be used. I was not about to plug it in just like in the photo
, I just wanted to provide a visual aid for my questions. I'll probably build a wood enclosure.
Hello everybody, another bandwagon jumper over here...
...after reading all 46 pages, my head feels slightly inflated and all that stuff, you guys wrote, is kind of mixed up inside somewhere...
While reading, I tried to source some trannies and found localy available Monacor LTR-110 (is this the right stuff? http://www.chipoteka.hr/artikl/8011601421).
As I am not soldering iron wizzard I would really apreciate if someone (McGyver?) could make some "DIY DAC/Monacor LTR-110 for Dummies" instructions. I know I should be able to extract that info from aforementioned 46 pages, but it is all mixed up in my head and I'm affraid that I'll fry something.
I have upsampling/USB version of DAC.
Thank you!
...after reading all 46 pages, my head feels slightly inflated and all that stuff, you guys wrote, is kind of mixed up inside somewhere...
While reading, I tried to source some trannies and found localy available Monacor LTR-110 (is this the right stuff? http://www.chipoteka.hr/artikl/8011601421).
As I am not soldering iron wizzard I would really apreciate if someone (McGyver?) could make some "DIY DAC/Monacor LTR-110 for Dummies" instructions. I know I should be able to extract that info from aforementioned 46 pages, but it is all mixed up in my head and I'm affraid that I'll fry something.
I have upsampling/USB version of DAC.
Thank you!