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DAC tour

It's certainly interesting - the idea that the internal psu chips may now be the limiting factor wrt noise floor. If I knew precisely what hardware was required I'd be tempted to try John's battery mod for my Regen: and if I didn't need the external 5V for my current DAC I'd be tinkering already.

And then there's the Super-/Ultra- Capacitor approach to consider......(is there a Hyper- in the offing?)

But given that JohnW has ruled out battery power for MDAC2, it's of only academic interest pro tem, except maybe to JohnK :)
 
davidjt said:
It's certainly interesting - the idea that the internal psu chips may now be the limiting factor wrt noise floor. If I knew precisely what hardware was required I'd be tempted to try John's battery mod for my Regen: and if I didn't need the external 5V for my current DAC I'd be tinkering already.
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Oh but you can easily try this - I have posted, on Audioasylum, the instruction for how to bypass the internal voltage regulator (low noise TPS7A4700, I think) & feed a 3.3V battery directly to the chips. The ones who tried it reported a large increase in SQ - I'll look for the link.

Edit: Ok, found it https://db.audioasylum.com/mhtml/m.html?forum=pcaudio&n=153125&highlight=jkeny&search_url=/cgi/search.mpl?searchtext=&b=AND&topic=&topics_only=N&author=jkeny&date1=&date2=&slowmessage=&sort=date&sortOrder=DESC&forum=pcaudio

BTW, it's far more than just a reduction in noise floor - it's all about stability of the power supply - voltage regulators seem to introduce some dynamic noise

And then there's the Super-/Ultra- Capacitor approach to consider......(is there a Hyper- in the offing?)
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I have different PS offerings now - battery PS, Supercapacitor PS & Hybrid (Battery + supercap) PS

But given that JohnW has ruled out battery power for MDAC2, it's of only academic interest pro tem, except maybe to JohnK :)
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Maybe? :)
 
Ciunas Audio said:
I was thinking of beameup who has a recently acquired streamer, I believe?
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After plugging in a 19V PSU which is allowed, this is the output from the /dev page on the Stream Box if that helps. You should ideally use an 18V PSU.

Power Status: 0
Board Revision: 1
Firmware Revision: 117
Voltage: 19.61 V
Current: 278 mA
Power: 5.45 W
DAC Voltage: 5.32 V
DAC Current: 0 mA
DAC Power: 0 W
Temperature: 41.9' C
Streamer Software Version: 1.001
 
beammeup said:
After plugging in a 19V PSU which is allowed, this is the output from the /dev page on the Stream Box if that helps. You should ideally use an 18V PSU.

Power Status: 0
Board Revision: 1
Firmware Revision: 117
Voltage: 19.61 V
Current: 278 mA
Power: 5.45 W
DAC Voltage: 5.32 V
DAC Current: 0 mA
DAC Power: 0 W
Temperature: 41.9' C
Streamer Software Version: 1.001
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Thanks, beammeup
I doubt the voltage once around 18V makes much difference with the internal regulators
Are you interested in trying a supercap PS? What is the diameter of the DC plug into Stream Box - I suspect 2.5mm but could be 2.1mm?
 
Perhaps I haven't digested the article properly - I thought I'd need to find an alternative 5V supply for the DAC if I modified the Regen. (The MDAC usb socket fell apart: fallback is a Topping d10, usb powered by the laptop.)
 
davidjt said:
Perhaps I haven't digested the article properly - I thought I'd need to find an alternative 5V supply for the DAC if I modified the Regen. (The MDAC usb socket fell apart: fallback is a Topping d10, usb powered by the laptop.)
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OK, I understand you now - yes if you need 5V output from the Regen then it's a more involved & probably not reversible tweak. Sorry, I don't ever use USB 5V so it's off my radar
 
Ciunas Audio said:
Thanks, beammeup
I doubt the voltage once around 18V makes much difference with the internal regulators
Are you interested in trying a supercap PS? What is the diameter of the DC plug into Stream Box - I suspect 2.5mm but could be 2.1mm?
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Interesting, but looking at your website it shows the supercap PS only able to deliver 10V max?

What would be fantastic is if you could create a PS with selective voltage outputs, and perhaps able to power more than just the one device without stress. For example, the Stream Box is 18V (as you know) but it would also be good to use the same PS to give clean power to a DAC requiring 12V. What a versatile unit that would be (as long as the extra load does not compromise the sound).

Here's a list so far:

Stream Box = 18V
sMS-200 Ultra = 9V
Auralic Aries Mini = 15V
Arcam irDAC = 12V

That's four devices, but I would only run two at a time (i.e. sMS-200 into irDAC or Stream Box into irDAC etc).
 
beammeup said:
Interesting, but looking at your website it shows the supercap PS only able to deliver 10V max?
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Yea, I don't like to over-promise & prefer to introduce new products organically. Up to 10V I can use the existing case & have the charging scheme sorted - above that I have to go to bigger case & have to revert to an alternative charging scheme. I haven't worked out all the costs yet.

What would be fantastic is if you could create a PS with selective voltage outputs, and perhaps able to power more than just the one device without stress. For example, the Stream Box is 18V (as you know) but it would also be good to use the same PS to give clean power to a DAC requiring 12V. What a versatile unit that would be (as long as the extra load does not compromise the sound).
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Yes, that's in my short term plans. I need to do some testing of the different approaches to charging which will allow multiple voltages to be drawn from the same capacitor bank while retaining reasonable voltage regulation for each voltage. The continuous current draw is dependent on a number of limiting factors - the main one being the charging PS current output but also the charging & balancing scheme used but the supercaps are capable of delivering enormous instantaneous current which is also one of the main characteristics of LiFePO4 which makes the PS super stable & is crucial for audio (as witnessed)

Here's a list so far:

Stream Box = 18V
sMS-200 Ultra = 9V
Auralic Aries Mini = 15V
Arcam irDAC = 12V

That's four devices, but I would only run two at a time (i.e. sMS-200 into irDAC or Stream Box into irDAC
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Thanks - yes, those 4 voltages plus 5V & 7V would be my output targets.

I'm eventually thinking of a Supercapacitor PS that would allow the user to control the output voltage. Each PS would be designed for a max voltage level but the user could dial any voltage down from that. So a 10V max PS could be dialed down to 9V, 8V, 7V, etc (or any setting in between) & the second output voltage half of the max voltage setting. But this will probably require some microprocessor control.
 
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beammeup said:
That's great - as long as flexibility does not compromise the sound in any way shape or form
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Would I do that?? The proof is in the pudding
So are you interested in auditioning one of these PSes?
I might start a thread on a PS tour if Tony is Ok with it?
 
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Ciunas Audio said:
Would I do that?? The proof is in the pudding
So are you interested in auditioning one of these PSes?
I might start a thread on a PS tour if Tony is Ok with it?
Click to expand...

Yes I am - but I can't decide what device to try it on so that you send me the right voltage. My thoughts are either the Auralic Mini requiring 15 Volts - but would also like to try the Stream Box at 18 Volts <-- so let me get back to you once I have made my mind up. However I have made my mind up in wishing to try out your PSU, it's a "yes". Thanks.

Also it sound odd when you say "audition a PS" - so I am listening to a power supply am I :)?
 
beammeup said:
If I only have one choice - I would like to try the 15V version for the Auralic Mini if that's OK.
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I'll see what I can do.
beammeup said:
Also it sound odd when you say "audition a PS" - so I am listening to a power supply am I :)?
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The Power delivery system is the foundation of all audio - amplifiers, for instance, are simply just a modulation of the power supply in correlation with the input signal. In all cases where I've tried battery power on devices in the playback chain (including PCs) it has improved the sound. We could go into the reasons for this but that's for another day & it has been trashed out on numerous audio sites before.

The proof is in the pudding
 
BTW, only systems that are USB 2.0 (or above) & UAC2 (USB Audio Class 2) compliant will work with the ISO-DAC - there's no point in trying some funky setup unless you can verify this info.
 
Is the ISO-SPDIF still doing the rounds? If it is I'd like to give it a try in my audio chain.
 
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