Uln8 on SLA power

[Abstraction]

Some time ago someone said they were going to try powering their ULN8 with one of the Red Wine battery power supplies. I would like to hear how that worked out. (I am dealing with the filthiest imaginable AC.) Thanks.

 

[silverlight]

That was Barry Diament. I also recently got an RWA Black Lightning SLA power supply for the ULN8 (Model 4 in my case). I have done a lot to condition the AC power and my comparison (not entirely fair versus raw outlet power as thousands of dollars of power management investment compared the battery power from RWA which is a fraction of that cost). I need to do some A/B comparisons, and have been busy with work until this weekend and will have the next week off for the holidays so will get some listening in. However notwithstanding the above, the change was quite significant swapping in the battery supply, but want to listen more critically to all aspects of the change and sound because it's a little complex (some elements were immediately better and cleaner sounding, others were different, and want to be able to do some longer comparative listening sessions to have a better feel for the overall change in character).

 

[cfmsp]

 

Thanks, and do keep us posted. I've not jumped into Vinnie's queue yet.

 

clay

 

 

[silverlight]

Finally had a chance to do some critical listening tonight with / without battery power. I had also wanted to let some other things settle in before doing the comparison (including a couple acoustic treatments breaking in within my brain system..... that's a joke... sort of). So the comparison is: (1) inexpensive Signal Cable AC cable feeding the Model 4 stock switching PSU and (2) Red Wine Audio Black Lightning SLA battery power supply. Two interesting side notes: (a) tried a few more expensive AC cables and the Signal Cable power cord was by a healthy margin the most transparent sounding, go figure! (just checked, it's the MagicPower Video cable $49, the one I use for my TV); (b) Vinnie suggested 4-5 hours of use from a charge with the power supply, and I shut the system down after 7-8 hrs continuous use and it was still going strong this past weekend. Also pulled the Cary preamp and just ran direct to amps to minimize other interactions. Still using the Mogami Gold TRS to XLR cables (and expect a nice pop in performance when the new adapters are made and in the system combined with the ASI Liveline XLR's). One last comment on the Black Lightning product from Red Wine Audio - it is extremely well made, a gorgeous unit, and extremely well designed with it's auto-charging "SMART" system.

 

So the difference between the two power supply setups, pretty meaningful, but not 100% one-sided. Battery power -- the mid and high frequency transparency and low level detail is unquestionably better with a lower noise floor, more immersive soundstage and depth. Really nice improvement here. The only catch, and it may be a matter of personal taste and the matching with other system components, is that the bass is a little "heavier" (I certainly wouldn't go as far as saying "boomy" or "wooly") - perhaps best described as being a little more subtle and therefore better controlled sounding with the AC power supply. I haven't hooked up my solid state amps to see how this translates in an all SS setup. The result is that the AC power sounds a little more integrated from the lowest frequencies up to the mids, but more "veiled" in the mids/highs. I'll continue to listen and occasionally switch it up, but it's hard to give up the improvement in realism derived from improved transparency of the mids/highs. So the next logical question of course is what a good linear power supply (i.e., Paul Hynes) would sound like. The switching AC supply sounds very good in my setup, but overall I like the battery setup better in my system (others may favor the AC if their systems are on the analytic side). Looking forward to hearing Barry Diament's thoughts on linear PSU compared to battery and stock switching AC.

 

 

 

[machinehead]

Has anyone tried making the SLA charging kit from Parts Express, I think it is under $200 for the battery and charging kit, wonder if there is anything special with the high end stuff?

 

Too bad you couldn't split the digital signal and run the bass frequencies through a DAC run from AC and the Highs and Mids on SLA

 

[Bob Stern]

Although $675 seems reasonable to upgrade a ULN-8, for those of you (Clay) who have a ULN-2, I would not be inclined to make a larger investment than the $200 Parts Express battery power supply. For slightly more than the cost of the $675 Red Wine, I expect that upgrading to a $2500 Ayre QB-9 would provide a much more dramatic improvement.

 

Admittedly I auditioned the ULN-2 much less extensively than the ULN-8. However, during my brief audition, the ULN-2 struck me as no better than my Bryston DAC, whereas the Ayre had a purity and subtlety that clearly surpassed the Bryston.

http://www.computeraudiophile.com/content/Amarra-4-based-ULN-8-Ayre-Bryston

 

[Thomas J]

I would personally install an excellent Hynes supply, and would upgrade every regulator (there are probably several). Upgrading regulators probably gives the greatest performance boost.

 

I would also consider separating out the more delicate clock regulators by running them from their own dedicated supply. This would push back the common point to the AC line itself.

 

The overall result from all of the above---which would cost probably no more than $675, probably less---would probably allow the ULN-2 to better $10K+ machines.

 

[Guest Claude]

Hi Silverlight,

You seem to have gone the power upgrade path very consequent. Have you tried to change the fuses in your equipment. I just changed fuses in mine to furutech fuses. I also tried fuses from AHP (are distributed by PS audio in the us) and the hifi tuning silver fuses. I am deeply impressed. The change is as dramatic as installing a dedicated AC for your system (with special fuses and power lines). But much cheaper. The Fuse costs 20 Euros in Germany. Very good investment. I can wholeheartedly recommend this tweak.

Happy holidays and thanks again for answering my ripping questions.

Claudius

 

[cfmsp]

Hi Bob,

 

Merry Christmas, and thanks for thinking of me. I always enjoy your posts, as I almost always learn something.

 

I especially appreciate your knowledge of Mac arcanity that even I don't yet understand.

 

"For slightly more than the cost of the $675 Red Wine, I expect that upgrading to a $2500 Ayre QB-9 would provide a much more dramatic improvement."

 

given that I already have a ULN-2, the cost difference between a Red Wine and an Ayre is more than $1800 - and that's not even factoring in the cost of an expensive USB cable 'worthy' of the Ayre.

 

Your math and your comments DO seem relevant for someone anticipating buying a new ULN-2, provided they could stretch their budget up to the Ayre price at time of purchase.

 

As for me, I happen to really like the sound (or lack thereof) and the features of the ULN-2.

 

There's also the matter that the Ayre is a one-trick pony - no volume control (i.e., requires a preamp), no inputs for my Apple TV / Oppo DVD player / AE, no preamp/mic inputs, etc.

 

There's also other factors in support of one of Vinnie's battery devices, which you couldn't have known, of course. My upgrade path will be to a ULN-8 (or other MH manufactured unit), and therefore the Red Wine would be (re)usable then as well. Also, the 24V output of the Red Wine can even be 'split' to operate multiple devices.

 

OTOH, based on Geoff's review, I'm a bit perplexed, and therefore maybe I will take your advice, and try out the kit. Thanks for suggesting it.

 

I've just received my second 'batch' of Alan Maher AC circuit tuning gear, and will see how things go after it is installed and settles in.

 

Thanks again,

Clay

 

PS,

Just out of curiosity, in your audition of the ULN-2, did you use the switching power supply provided as standard? I use a custom linear power supply made by Gordon, which does improve the sound. As Thomas suggests, we don't know that a ULN-2 with more refined power won't equal, or even surpass, the Ayre.

 

 

 

 

 

 

 

 

 

 

 

[Bob Stern]

Merry Christmas, Clay!

 

The ULN-2 and ULN-8 ship with the same external switch mode power supply, and that is what I used to audition both of them. The standard power supply certainly did not disguise the impressive qualities of the ULN-8.

 

The ULN-2 and ULN-8 both appear to include internally a switch mode DC-to-DC converter because their rated power consumption is independent of the DC input voltage. That could improve the immunity of both models from noise in the external power supply. Even so, it's interesting that Thomas and John Atkinson found that Gordon Rankin's linear power supply improved the ULN-2.

 

[silverlight]

Hey Claude - happy holidays and hope you're well. thanks for the tip on the fuses. I have done it in the past (hifi tuning cryo fuses), but haven't done it yet in my new amps and pre so a good reminder! I'll go through all of my equipment and make sure to upgrade them as I do recall it being a great tweak. Did you like the Furutech better than the other two you mention?

Best,

Geoff

 

[Guest Claude]

I started of with the Hifi Tuning Silver Fuses. The sound was more dynamic, better resolution and sparkling hights. But the presentation lost considerable weight and bass energy. If you need that extra sparkle and your system is rather warm or has a dark timbre, this just might be perfect. I preferred the AHP fuses (Copper). They gave my system more weight, everything sounded more natural, bass energy increased by a considerable amount. When I bought the Ayre QB9 I wanted to buy some AHPs right away. But my dealer almost begged me to try the pFurutuech. So I bought Furutech and AHP for the Ayre and still had some hifi tuning fuses. I listened to them not in A/B but had them in the system for at least one day before changing. After a week or so I had a clear preference for the Furutech. I bought 6 more Furutech fuses and changed all fuses in my system. Wow! The Furutech is the perfect combination of the virtues of the AHP and Hifi Tuning. Better resolution in all areas. More room, more space between instruments. Very neutral sounding.

My ranking:

1. Furutech (100%)

2. AHP (90%)

3. Hifi Tuning (85%)

We optimized the system of my brother (a recording engineer) by combining all three fuses. In his system just changing one fuse, could change the sound to the better or worse by a considerable margin. We put a Furutech in his Wadia DAC and found out, that direction of the fuse matters! I have no idea why that is. But there was a clearly audible difference.

I am interested in your findings.

Claudius

 

[cfmsp]

"The ULN-2 and ULN-8 both appear to include internally a switch mode DC-to-DC converter because their rated power consumption is independent of the DC input voltage."

 

You're not the first to mention that here. Along with the previous mention came the suggestion that this would preclude noticeable impact of (upgrading) the switching power supply on the sound of the MH units.

 

If so, might the impact of the switching supply only then manifest itself in corrupting the AC of the other devices in the chain? ...and thereby result in (correct?) belief that the linear supply DID improve the sound?

 

curious,

clay

 

PS, the more I (think I) know, the less I understand.

 

PPS, as I stated elsewhere, I think one-box solutions will make a comeback in 2010 for the simple reason that 'everything affects everything' in the computer digital audio playback chain, and some (of us) will undoubtedly tire of being "couch potato" engineers.

 

 

 

 

 

 

[Bob Stern]

"might the impact of the switching supply only then manifest itself in corrupting the AC of the other devices in the chain? ...and thereby result in (correct?) belief that the linear supply DID improve the sound?"

 

I hadn't thought of that, but I think you hit the nail on the head!

 

That argues in favor of providing separate AC filters to isolate each audio equipment (and the computer), as in the Monster brand filters designed by Richard Marsh or the PS Audio "Quintet" filter with 5 filters to isolate 5 components.

 

Incidentally, the Chord DAC being discussed on another thread uses a switch mode power supply.

 

In any event, it's unclear that a linear AC power supply inherently generates less noise than a switch mode power supply. A linear AC power supply actually is not linear at all. The rectifiers only conduct current during a small portion of the sinusoidal cycle of the AC power, so there is a high current surge as the power supply capacitors charge up during that small portion. Also, rectifiers inherently produce RF noise, although some types of rectifiers produce much less noise than others.

 

[cfmsp]

 

"That argues in favor of providing separate AC filters to isolate each audio equipment (and the computer)"

 

I'd heard it recommended to keep digital equipment on a different circuit than analog - presumably for the reason noted above, keeping their cheap switching supplies from polluting the AC 'pool'.

 

I noticed the improvement with the linear supply BEFORE I embarked on 'tuning' my AC circuit. Re that, I'm relying on Alan Maher's products in the AC realm, which seem much more holistic in nature (and perhaps even new-agey) as compared to the products you mention.

 

I've been advised that my AC system is not yet ready for individual component-based solutions, i.e., I've still got more potential for treating the entire system, apparently.

 

I'll ask Alan.

 

Clay

 

 

 

[bmckenney]

I have heard that DAC's are considered analog components. Or that they should be powered on the same AC circuits or isolated line conditioners that the rest of the analog components are on. And I have heard that it does sound better this way. I've only heard about it, not heard it myself.

 

Bryan

 

[bdiament]

"..That was Barry Diament... "

 

Actually, the SLA supply I tried was from another source, not Red Wine.

I've also just tried a linear supply. Both have been returned.

 

The SLA supply gave and it took away. It gave in terms of a lowered noise floor (apparent when the volume is *way* up, during the quiet parts of very dynamic recordings --- i.e. the only times I notice noise in the stock supply). The flip side is it also removed the stupendously natural bass of the ULN-8, replacing it with one quite ordinary and considerably less defined than what I have become used to.

 

This is with the battery fully charged. As power is drained, I found the sonics followed the downward path.

 

With the linear supply, despite my best efforts, I could not reliably tell a sonic difference from the stock supply.

 

For now, unless and until I hear something truly better (regardless of what "theory" says), I'm sticking with the stock supply.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[silverlight]

Barry - for fun try out a few or borrow some different power cords that feed the stock switching unit. I found a wide variation and improvement selecting a different cable. Might get you that improvement.

 

 

[bdiament]

Thanks. Different AC cords are in the plan (for the '8 as well as the amps)... if there's ever time 'round here.

 

Best regards,

Barry

www.soundkeeperrecordings.com

www.barrydiamentaudio.com

 

 

[ferenc]

I have a friend who is using an ULN-2 as a Firewire-SPDIF converter to his Meitner DAC through AES/EBU. He ordered a Paul Hynes power supply, custom built for the ULN-2. He is very happy with it, after the orginal PS and a battery PS, likes the Paul Hynes PS much more than the rest.

 

Ferenc

 

[cfmsp]

 

Silverlight,

so what cable did you wind up with for the BL? one of Alan's?

 

 

Barry,

Your inability to detect difference with linear power supply is/was predicted by those who believe the Metric Halo dc-to-dc conversion should minimize any impacts of such.

 

That I did notice a difference in my poor (pre-Alan Maher tuned) environment with Gordon's linear PS has been chalked up (by me, with Bob Stern's support) to minimizing the impact of the switching power supply on the AC circuit being shared by other equipment, and this still impacting the overall sound of my system.

 

This seems consistent to me with your results, given that you have a dedicated AC circuit which probably wouldn't as likely feel the effects of a switching supply on other pieces of gear.

 

cheers,

clay

 

 

[silverlight]

Vinnie made a very nice power cable with the required terminations for use with the ULN8 (higher quality terminations than the standard one MH uses).

 

As for the power cord swapping I did on the stock PS, I was surprised with the result, I tried 4 or 5 different cables, several of which I'd put in the better cable category (no, not $2-10k power cables), and the least expensive one sounded the best, the Signal Cable mentioned earlier. The Maher reference cable sounded veiled in comparison, a Black Sands Violet II gold series sounded bright and edgy. Those were probably the most different sounding cables. If my experience was any indication, one could get a lot of mileage out of optimizing the power cable selection (and maybe not have to spend too much).

 

 

 

[silverlight]

Man, sweet upgrade! I certainly wasn't expecting that! Upgraded the fuse in the Bolder PSU for the Mac Mini, and the fuses for the monoblocks (and the pre but don't have that in the chain right now). This is an absolute must do for anyone wanting to improve SQ as you've said!