|Model:||Signal SU/DU balanced conditioner|
|Category:||Power Conditioner/Surge Protector|
|Suggested Retail Price:||$varies|
|Description:||balanced power conditioner|
|Manufacturer URL:||DIY by Jon Risch|
|Review by rhyno on July 08, 2012 at 07:07:39|
IP Address: 220.127.116.11
|Add Your Review|
for the Signal SU/DU balanced conditioner
Signal DU-3 Balanced Transformer
I’ve tried the following tweaks / products for AC conditioning, with varying levels of success:
• Dedicated lines
• High grade in-wall AC
• Alan Maher CBFs and ERS paper in breaker box
• Hammond 193-L chokes around house
• Environmental Protections EP2050 (whole house filtering / protection)
• Oyaide WPZ wall plate, R-1 outlets, along w/ Maestro outlets
• R-C and Cap arrays (latter using Teflon caps, 1.0 uf to .01uf) around the house
• Bybee filters (previously on hot or neutral, now on ground)
• Audio Magic Pulse Gen DX
• High grade power cords by various manufacturers (now using TG Audio and Tel-Wire)
• Power conditioners by TG Audio (in service), Weizhi, Acoustic Revive, Bybee Tech, Silver Circle Audio, Audience, Isoclean. (note: a mix of both passive and active; I’ve come to like passive more).
So I’ve been trying a while to get 1am power to 11am, with varying (but never consistent) success.
Picked up a DU-3 on ebay for $300 (mounted to an oscilloscope stand---anyone interested?!?) and wired it for balanced AC per Jon Risch’s website. Primary has a 15a fast blow fuse, secondary is hard wired into a custom AC cord that has an IEC attached to its end, permitting it to plug into my TG Audio (passive) outlet boxes, which feeds all line level electronics (amp on diff circuit). Maestro outlets exclusively in TG box.
Quick test of wiring showed I was getting 70/70 off the secondaries! When I triple checked my wiring, no errors; measuring at the wall (July in Houston), my voltage was 138/0 (I’m using a Fluke DMM). Yowser!
So into the rig it goes. After a few hours, I noticed how the sound had an overabundance of mid-range energy and NO top end. Was rather disappointed in the results, and then remembered: I still have that Teflon cap array (1.0 to .01) plugged into the same outlet as my amp. So out it came.
Now, where were we? Oh yes. I was about to write about the best thing (behind dedicated lines) I ever did for AC. With the DU-3 in the path, bass depth and impact were more pronounced; top end energy was extended without aggressiveness or any whitening / hardening of the balance the way 11am-9pm power is notorious for. The DU-3 allows me to hear much deeper into each recording, revealing more information than previously experienced (lowest level information in a recording is always obscured by the noise floor of the system—clearly the DU-3 lowered my rig’s noise floor quite a bit). I consistently noted these results regardless of volume setting, though volume settings on my preamp (Audio Research Ref3) were consistently higher than before, which I always take as being evidence of the removal of an unnatural distortion (same thing happened when I introduced dedicated lines and room treatments).
While nothing would please me more than to say it completely removed the up & downs associated with summer power (137vac!), I don’t think its that good (as sonics are still better late at night)…but its done more for my summer power woes than any other product I’ve come across. Its staying, and strikes me as the 2nd best thing I ever did for power (heck, it might make dedicated lines unnecessary, I just didn’t tweak in the sequence to test that).
Downsides: time consuming (1 day) to build properly, heavy, and kinda bulky. Doesn’t address over-voltage situations.
Finally, much appreciation to two gents in particular: Jon Risch (for coming up with the formula, and for having the plans on his website) and Dave Garretson (for always pushing the art of tweaks and building such a nice box, and posting pics, that I copied it almost screw for screw---the weight of the tranny requires a well-engineered box to ensure stability; Dave’s design does that).
|Product Weakness:||big, heavy, DIY|
|Product Strengths:||wonderful and cheap|
|Preamplifier (or None if Integrated):||Audio Research Ref 3|
|Sources (CDP/Turntable):||Esoteric P/D02, Modwright 5400|
|Speakers:||Rockport Merak / Sheritan2|
|Cables/Interconnects:||TG Audio, Audioquest|
|Music Used (Genre/Selections):||varying|
|Other (Power Conditioner etc.):||TG Audio|
|Type of Audition/Review:||Product Owner|
When I triple checked my wiring, no errors; measuring at the wall (July in Houston), my voltage was 138/0
138Vac is way too high. If the mains voltage is that high you should be replacing burned out incandescent light bulbs quite regularly.
If the power utility transformer that is feeding your home is a single phase, split phase xfmr, that means L1 hot to L2 hot lines measure 276Vac. (138V - 0V - 138V ..... 138/276Vac.) (Nominal is 120/240Vac.)
Try another volt meter!! If the readings are the same contact your utility power provider......
Quick test of wiring showed I was getting 70/70 off the secondaries!
140Vac line to line is way too high.
126Vac RMS should be the max....
I personally would not want more than 124Vac max.
In my research of going balanced in the archives I didn't find much talk about voltage which to me is a big factor if considering going DIY.
Jon states on his website that the signal tranformers have a no load to rated load regulation of around 5% or better.
I just got a SU-2 online and started some test across all configuration while using a heater with a variac that I should be able to report on tomorrow. Initial findings are around 5% half loaded and closer to 10% almost fully loaded.
I agree with jea48, call you provider or better yet try to contact the rep for your area.
one pic of my enclosure, a 12x12x8 electrical box.
1) sent the unit home w/ a buddy who has very good ears, and a very good system. it made a marginal diff in his rig, which he (and i) admit is in stark contrast to the improvement it made in mine. so YMMV.
2) he also brought over an AC cord that had a bad connection in it. it was used downstream (ie receiving balanced power, and feeding to a preamp). when it shorted, it killed the fuse on the primary. replaced it, and all was well. so, safety first kids.
The Jon Risch website is no longer available. How can I get it?
You should be able to address your over voltage issues by moving down one tap or two on the secondary. Be sure you check the output voltage with all your equipment on line as the load can sometimes drag the voltage down a bit.
If your Fluke DMM is not a true RMS meter, you may not be getting an accurate voltage reading.
Averaging meters tend to read low not high compared to a true RMS meter on a non sinusoidal waveform.
The power from the wall should be sinusoidal and averaging meters are usually calibrated to a sinusoidal waveform. So the difference between true RMS and averaging should be minimal.
But the meter could still be the problem if it is out of calibration.
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