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At last... (Audiolab) - part VII

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Hi John
yes I tried both digital inputs but I read on display same info.. no sync, 8200CD for some reasons does not recognize CD850 MkII as a transport via their coax digital output. So problem was not resolved. Any additional help would be welcome.

Thanks in advance

Miki

JohnW said:
Hi Miki,
If I understand your question correctly, the Kenwood DP5090 works with the 8200CD as a CD Transport (So the 8200CD is operating as a DAC) - while your CD850 MkII does not work with the 8200CD (in DAC Mode).

If correct, have you tried that the SPDIF output of the CD850 mkII works with other DAC's?

Have you tried both Digital inputs of the 8200CD?

John
Click to expand...
 
miki166 said:
Hi John
yes I tried both digital inputs but I read on display same info.. no sync, 8200CD for some reasons does not recognize CD850 MkII as a transport via their coax digital output. So problem was not resolved. Any additional help would be welcome.

Thanks in advance

Miki
Click to expand...

Odd - I'd refere to my ealier question, have you tried your CD850 MKII with other DAC's?

John
 
John W - Do you have any idea if/when the MDAC might go on sale in New Zealand? I've tried finding out from the distributor but he's not talking to me at the moment.

Thanks
John
 
I checked the Audiolab site and I'm really convinced I want and need a DAC with pre-amp and HT-bypass. (Denon 3808 as surround-processor, external amp for power).

I'm stil in doubt between the 2 offerings that would fit my requirements:
- 8200DQ, as DAC/pre-amp/HT-bypass;
- M-DAC (DAC/pre-amp) + future power-supply upgrade (HT-bypass).

why should I get the M-DAC and wait for the power-supply upgrade ?
what benefits would an M-DAC-setup bring me over and above getting a 8200DQ ?

I looked at the specs, read both manuals and I can only see a delta in dynamic range.
 
Hi John, any info on the collection of units yet? Tomorrow is the last day that i will be able to personally collect my unit, it's courier and chance after that onward to Greece.

Steven.



p.s if the units are here i am happy to pay super speedy delivery to Shrewsbury no problem.
 
Gefilus said:
Hi,

In an ealier part of this thread (I think it was part V) this device was mentioned: http://electronicsshop.dk/galvanisk_isolation.htm?currency=EUR

Planning to purchase one for MDAC, depends on if/when JW is prodeeding with his isolator design.
Click to expand...

Yea I want to verify the quality before purchasing and was also interested if John was producing one himself. I don't want to add anything in the chain which would cause issues. So really just wanted a verification on a product to use with the MDAC.

I also read earlier that when used in conjunction with the Mac Mini no difference was heard. I have no idea how noisy my usb port is so spending £30 on one of these sounds like a plan for the time being until I find a suitable hi-res streaming device.
 
sam_cat said:
Nothing here either, guessing John is running a touch behind.

Sam
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He is a busy man who goes well above and beyond for the members on here (not a dig at you btw) :)

I'd also wager like most inventors his filing system is between his ears ;)
 
scubaboy said:
Hi John, any info on the collection of units yet? Tomorrow is the last day that i will be able to personally collect my unit, it's courier and chance after that onward to Greece.

Steven.



p.s if the units are here i am happy to pay super speedy delivery to Shrewsbury no problem.
Click to expand...

scubaboy,

I'll insure you get your unit to Greece - (are you living there now?)

John
 
Hi John, i really, really don't want to bother you with this, as you've gone above and beyond already and i'm sure that you are still ridiculously busy.

Yes, i have been living in Greece for the last few years and will be on my way back over there on Friday. I had a window of a week to come to blighty and see my mum and get some presents for my children and ONE for a slightly bigger kid! Everything crossed did'nt work this time, c'est la vie.

Steven.
 
JohnW said:
Hi Jo,

The USB interface conforms (electrically) to the USB 2.0 Spec, but its a USB1.1 Device - this simply means that you can use the MDAC on a USB 2.0 Bus...

John
Click to expand...

Apparently it's common for manufacturers to publish spec. as USB 2.0 however there are two flavours to be aware of: 'Full Speed' USB is only 12Mbits/second as in USB 1.1; whereas 'Hi-Speed' USB mode is capable of a much faster 480Mbits/second. And of course USB 3 is out there too.

I fell foul of this when I bought a USB 2.0 Olimex isolator from Farnell. I was able to prove it was only working at what I'd call USB 1.1 speed and got a full refund. Full marks to Farnell for customer service.

Seems from their ad http://electronicsshop.dk/galvanisk_isolation.htm?currency=EUR the USB2ISO has the same performance as USB 1.1.

From what John has said elsewhere this is perfectly adequate for 24 bit 96KHz as provided in the CDQ and MDAC but NOT quite good enough for 192 KHz. Several PFM'ers have reported good results with these isolators but I was expecting proper 'Hi-Speed' USB 2. - but we won't need this now with the new transport in the works :)
 
Hi John,

You've posted a tantalising list of upgrades for the MDAC:

A. Transport GBP 389
1. CD with clock input
2. 192KHz 24 bit async USB to optical SP/DIF input to MDAC
3. DLNA control point, WiFi connection

B. HQ PSU for MDAC (single ended to balanced conversion?) below £300
4. Power on/off 12V switching
5. Remote controlled AV pass through via MDAC

C. Stereo Amplifier
6. XLR inputs, can be used as a Stereo Amp, Bi-Amp or Bridged
7. 100W per channel class A Mosfet OPS with CROSS (with a twist)

Would it be practical to revise the transport to be CD only and move options 2 and 3 into to an 'auxiliary' box containing the HQ PSU and options 4 and 5?

From my point of view I'd want the PSU, isolated 192KHz USB and 12V power on/off for your new amp, but not the other features so this would be more cost efficient. Maybe a modular set of upgrade options would be popular?

Is there any chance you'll build a monoblock version of the amp?
 
Just reading head-fi.org findings and it looks promising. Just looks a bit unfinished in its shrink wrapped plastic which doesn't exactly seal the unit from dust

Cables: You need two 1.8 meter USB A-B cable to connect to the PC and to your
USB isolated device. Note these cables should be with LOW resistance (under 1
ohm) and good insulation, on the market there are cheap cables with HIGH
resistance (above 1 ohm) and poor insulation which are not good for USB
connection and cause signal fading and lost of communication packets.

Power requirements from usb on laptop :

+5V from USB_HOST, in this case maximum current available depend on the
maximum current which PC USB host can provide and may be in 100-500mA
range
 
So got these USB cables 2*1.8m

http://www.tlc-direct.co.uk/Product...w=1.8M+cable&gclid=CIGQmcOVmawCFYEZ4QodiggFPQ

John...>

About to push the button on the olimex usb isolator, but before I do just wandered about the test file bit perfect test and the other measurements showing buffer status over/under flow on the MDAC. Would these show any issues regarding 2nd order jitter with noisy usb ports ? If it does highlight deficiencies then I'll hold off and test my laptop first.

Thanks
 
Phil,
I bought one of the Danish isolators. It hugely improved the output from an old IBM Thinkpad running XP and foobar. Advantage over Olimex is that you only need one USB cable to hook it up.
 
Hi PhilCTTE,

The USB isolator will not effect the Bit Perfect test results - Your are correct in saying that the USB Isolator reduces second-order effects (Breaks Ground loops - reduces RF leakage etc).

John
 
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