I have mine plugged in for years with no problems, but others have reported problems with some switching laptop power supplies.
Equi=Tech Wall Cabinet System; whole system power solution.
- Thread starter Mike Lavigne
- Start date
I have mine plugged in for years with no problems, but others have reported problems with some switching laptop power supplies.
Bruce B
WBF Founding Member, Pro Audio Production Member
The only thing I was told to worry about was light bulbs. I plug everything else into it though.... even wall warts for computers and such
I wonder if those Equi=Tech wall panels are CE approved for use in Europe? I want one.
The other thing to be wary of is plugging a UPS into that as well. there are some UPS topologies (sorry, don't remember which) which can cause noise issues and /or not really like being on a balanced line.
Since my HTPC is also my automation PC, I need it on a UPS, so neither is on balanced power, but the rest of the rig is.
i cannot comment on the technical perspective of the implications of balanced power and circuit design. all i can say is that when i compare pretty much any of my electrical components 'Equi=tech power' to 'dirty power' side by side; 100% perform better to my ears with the 'Equi=tech'.
the most dramatic transformation was with my darTZeel NHB-108 stereo amplifier. the 108 has 2 'red-orange' eyes on the front that glow, and when the amp nears clipping they will go brighter in degrees. prior to the Equi=tech those lights would sometimes get brighter in the pace of the music when pushing the amp. after the Equi=tech the power supply was so much more stable that i never saw those lamps get bright again.
obviously my ears told me it sounded much better. but those lights were a much more profound message about what was happening. when you have a modestly powered amp that has suddenly grown balls that alone was worth the whole cost of the Equi=tech by itself.
i now am using far more powerful dart amps, and i know that they 'like' the Equi=tech since i had them for a 30 trial 6 months before i had the Equi=tech.
As Bill Whitlock writes about balanced power:
“Balanced power” or, more properly, symmetrical ac power is a seductively appealing concept.
However, its proponents often mistakenly assume that equipment has precisely matched
capacitances from each leg of the power line to chassis (C1 and C2 or C3 and C4) when they
explain how it itcancelsly ground noise. Of course, if this were true, capacitive noise currents from
each 60-volt leg would then be of equal magnitude and opposite polarity, and completely cancel.
But the assumption is not valid for the overwhelming majority of real-world equipment, whose
capacitance ratios are often 3:1 or 4:1. Even balanced power proponents admit that actual noise
reduction is usually under 10 dB and rarely exceeds 15 dB (recall that 10 dB noise reductions
are generally described as “half as loud” by listeners). And it’s not likely that equipment
manufacturers will ever adopt expensive power transformers with capacitively “balanced” primary
windings or RFI filters that use precision capacitors.
But balanced power can make cost-effective sense in some systems. One example might be a
video duplication facility having 50 unbalanced (coax) video interconnects and hum bars at an
unacceptable level of !30 dB. Here, the 10 dB improvement likely from balanced power (or
“technical grounding” for that matter) might reduce the hum bars to a more acceptable level of
!40 dB, effectively solving the problem. But, for audio, a 10 dB improvement will rarely make the
difference between unacceptable and acceptable performance!
In reality, many of the benefits often ascribed to “power treatment” schemes are simply
due to plugging all system equipment into the same outlet strip or dedicated branch
circuit. For obvious reasons, this is always a good idea!
from page 39
UNDERSTANDING, FINDING, & ELIMINATING GROUND LOOPS IN AUDIO & VIDEO SYSTEMS
Bill Whitlock - president
Jensen Transformers, Inc.
http://www.jensen-transformers.com/an/generic seminar.pdf
“Balanced power” or, more properly, symmetrical ac power is a seductively appealing concept.
However, its proponents often mistakenly assume that equipment has precisely matched
capacitances from each leg of the power line to chassis (C1 and C2 or C3 and C4) when they
explain how it itcancelsly ground noise. Of course, if this were true, capacitive noise currents from
each 60-volt leg would then be of equal magnitude and opposite polarity, and completely cancel.
But the assumption is not valid for the overwhelming majority of real-world equipment, whose
capacitance ratios are often 3:1 or 4:1. Even balanced power proponents admit that actual noise
reduction is usually under 10 dB and rarely exceeds 15 dB (recall that 10 dB noise reductions
are generally described as “half as loud” by listeners). And it’s not likely that equipment
manufacturers will ever adopt expensive power transformers with capacitively “balanced” primary
windings or RFI filters that use precision capacitors.
But balanced power can make cost-effective sense in some systems. One example might be a
video duplication facility having 50 unbalanced (coax) video interconnects and hum bars at an
unacceptable level of !30 dB. Here, the 10 dB improvement likely from balanced power (or
“technical grounding” for that matter) might reduce the hum bars to a more acceptable level of
!40 dB, effectively solving the problem. But, for audio, a 10 dB improvement will rarely make the
difference between unacceptable and acceptable performance!
In reality, many of the benefits often ascribed to “power treatment” schemes are simply
due to plugging all system equipment into the same outlet strip or dedicated branch
circuit. For obvious reasons, this is always a good idea!
from page 39
UNDERSTANDING, FINDING, & ELIMINATING GROUND LOOPS IN AUDIO & VIDEO SYSTEMS
Bill Whitlock - president
Jensen Transformers, Inc.
http://www.jensen-transformers.com/an/generic seminar.pdf
So what is everyone's thoughts on cascading devices? Such as using the aforementioned MIT outlet with the Equi=tech, and then maybe through something like a Statement power cord, and then into a Sound Application RLS-1?
Too much?
Too much?
Mike,
Are you sure that the NHB-108 was not upgraded after you got the Equi=tech? You have just described the difference between the original 108 and the version with the offset upgrade.
Mike,
Are you sure that the NHB-108 was not upgraded after you got the Equi=tech? You have just described the difference between the original 108 and the version with the offset upgrade.
i got the SCNP upgrade for my NHB-108 in 2009, and got my Equi=tech installed over a year later in 2010.
with the SCNP upgrade no doubt that there was a noticable improvement in dynamics and heft. but those lights still would pulse to high SPL moments, although it took more to get them to pulse after the SCNP.
then with the Equi=tech i never saw them pulse again.
not to say that you cannot push them that far, but i never had occasion to.
there was a difference between the very earliest NHB-108 'A' and then the 'B', where with the 'B' you could adjust the DC offset to tailor the amp to loads of specific amplifiers. that was back in 2005-2006.
that's all from my memory, maybe i've got it wrong.
To put my mind at rest and to confirm what I was hearing, the use of an oscilloscope proved a revelation of what balanced power is capable of.
Noise manifests itself at the amplifier inputs, usually the RCA's outer shell, and most if not all amps are earthed to this shell. So if noise is at this level, the amplifier doesn't really care and makes the noise louder, cause that's what it does.
The scope leads were hooked on to the RCA outer shell of the amplifier and the wall socket earth in one measurement, the other measurement at the same point to the earth point from the Equitech balanced supply.
1. 50Hz + various other bonus frequencies of about 400mV (summed harmonics from an FFT) measured when powered up from the wall (TN earthing system).
2. Using the Equitech from the same point on the amplifier to the Equitech earth, the sum of all frequencies added to 7.6nV.... pretty close to nothing, still a way to go to true nothing, but a big improvement.
The voltage reduction of garbage is more than 70db ...is my maths correct?
The actual measurements are on this page.
No wonder the sound is a hell of a lot clearer, and fade to black takes on a new meaning, even from a 1kVA model Q.
From what I can research, the transformer in the Equitech has very tight regulation to ensure that the voltages across the 60-0-60 (120-0-120 in my case) are super balanced. They need to be capable of that, so the asymmetric noise created by the audio components cancel out correctly. The beauty of this system is that you can plug in wall warts, noisy SMPS, PC's along with the amps and Dacs (it does work) and the noise is well and truly out of the picture. The measurements included the whole system of laptop and Mac Mini power supplies, MPD-3 DAC, E-450 amp, tuner et al.
The Equitech is not immune to line transients caused by switches in your house, so the use of a spike suppressor power strip, isolation transformer work well in combination in front of the Equitech. I haven't tried a power conditioner since I don't have one, and one colleague opened up a Furman, and they are mainly capacitors to filter out harmonics which is fine, however they may adversely react with bulk inductance from isolation transformers and the Equitech. All I can report is what works at my place.
Noise manifests itself at the amplifier inputs, usually the RCA's outer shell, and most if not all amps are earthed to this shell. So if noise is at this level, the amplifier doesn't really care and makes the noise louder, cause that's what it does.
The scope leads were hooked on to the RCA outer shell of the amplifier and the wall socket earth in one measurement, the other measurement at the same point to the earth point from the Equitech balanced supply.
1. 50Hz + various other bonus frequencies of about 400mV (summed harmonics from an FFT) measured when powered up from the wall (TN earthing system).
2. Using the Equitech from the same point on the amplifier to the Equitech earth, the sum of all frequencies added to 7.6nV.... pretty close to nothing, still a way to go to true nothing, but a big improvement.
The voltage reduction of garbage is more than 70db ...is my maths correct?
The actual measurements are on this page.
No wonder the sound is a hell of a lot clearer, and fade to black takes on a new meaning, even from a 1kVA model Q.
From what I can research, the transformer in the Equitech has very tight regulation to ensure that the voltages across the 60-0-60 (120-0-120 in my case) are super balanced. They need to be capable of that, so the asymmetric noise created by the audio components cancel out correctly. The beauty of this system is that you can plug in wall warts, noisy SMPS, PC's along with the amps and Dacs (it does work) and the noise is well and truly out of the picture. The measurements included the whole system of laptop and Mac Mini power supplies, MPD-3 DAC, E-450 amp, tuner et al.
The Equitech is not immune to line transients caused by switches in your house, so the use of a spike suppressor power strip, isolation transformer work well in combination in front of the Equitech. I haven't tried a power conditioner since I don't have one, and one colleague opened up a Furman, and they are mainly capacitors to filter out harmonics which is fine, however they may adversely react with bulk inductance from isolation transformers and the Equitech. All I can report is what works at my place.
'Onepoint' don't put any value into that tradeshow type demonstration test.
Jim Brown writes:
At trade shows, misguided (unscrupulous?) salesmen often demonstrate their expensive
isolation transformers by showing a scope connected between neutral and the equipment
ground with and without the isolation transformer in use. Without the transformer,
there is noise between the neutral and the equipment ground due to normal
current flow on both conductors. With the transformer installed, the scope probe, still
connected between neutral and ground, is shorted out by the bond between neutral
and ground, so "that awful power line noise" seems to be killed by the transformer. But
that noise is not a fundamental cause of problems in equipment – no reasonable power
supply should pass power line noise to signal circuitry! More important, a properly installed
isolation transformer does reduce or change noise current on the equipment
ground (and may even increase it), and noise on the equipment ground is a primary
cause of noise in audio and video systems! For more on these noise coupling mechanisms
see the discussions of unbalanced wiring and pin 1 problems.
Power and Grounding for Audio and Video Systems
A White Paper for the Real World – International Version
Jim Brown - Audio Systems Group, Inc.
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf
Jim Brown writes:
At trade shows, misguided (unscrupulous?) salesmen often demonstrate their expensive
isolation transformers by showing a scope connected between neutral and the equipment
ground with and without the isolation transformer in use. Without the transformer,
there is noise between the neutral and the equipment ground due to normal
current flow on both conductors. With the transformer installed, the scope probe, still
connected between neutral and ground, is shorted out by the bond between neutral
and ground, so "that awful power line noise" seems to be killed by the transformer. But
that noise is not a fundamental cause of problems in equipment – no reasonable power
supply should pass power line noise to signal circuitry! More important, a properly installed
isolation transformer does reduce or change noise current on the equipment
ground (and may even increase it), and noise on the equipment ground is a primary
cause of noise in audio and video systems! For more on these noise coupling mechanisms
see the discussions of unbalanced wiring and pin 1 problems.
Power and Grounding for Audio and Video Systems
A White Paper for the Real World – International Version
Jim Brown - Audio Systems Group, Inc.
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf
There is a lot of confusion between the use of balanced lines in audio circuits and balanced power systems. Unhappily the subject can not be addressed in a few lines - it needs concepts such as inductive and capacitive coupling, signal ground and safety ground, common mode and differential mode noise and its rejection. IMHO, any simple explanation avoiding these words risks to be misinterpreted or even misleading.
One point is sure - noise in audio lines has very different characteristics from noise in power lines, and because we know a little about the first one does not make us experts in power lines. Very few people can mix both and try to correlated them - and I am not of them, although I can understand what is written in the excellent references of post #91 with a little help of Ralph Morrison "Grounding and Shielding Techniques in Instrumentation".
http://www.whatsbestforum.com/showthread.php?1137-Equi-Tech-Wall-Cabinet-System-whole-system-power-solution&p=148801&viewfull=1#post148801 should be the first post of the thread!
One point is sure - noise in audio lines has very different characteristics from noise in power lines, and because we know a little about the first one does not make us experts in power lines. Very few people can mix both and try to correlated them - and I am not of them, although I can understand what is written in the excellent references of post #91 with a little help of Ralph Morrison "Grounding and Shielding Techniques in Instrumentation".
http://www.whatsbestforum.com/showthread.php?1137-Equi-Tech-Wall-Cabinet-System-whole-system-power-solution&p=148801&viewfull=1#post148801 should be the first post of the thread!
what I want to know, if you don't need all the power of a wall mounted system, do the Q boxes give you the same clean balanced power ? From what I can tell reading, yes.
That is a question has crossed my mind on more than one occasion. I might even contact Equi=Tec and pose the question to them directly. If I do, I'll be sure to post the answer here.
Steve williams
Site Founder, Site Co-Owner, Administrator
@ Speedskater
Thanks for the link for Jim Brown’s paper. It’s a good read, with some points taken from Bill Whitlock, no doubt this has raised discussion before about balanced power.
Both authors seem to miss the point that any audio device with caps, transformer, SMPS can draw non sinusoidal currents from the AC supply.
For the microcosm within our humble home audio system the principles are the same for larger harmonic creators, VFDs and the like. Non sinusoidal currents create harmonics and for the frame of reference in the microcosm are significant like it is for all audio. Current distortion is typically 30%++ since the fault level of the supply is usually not that great, reduced by wiring, cascading smaller and smaller transformers, especially for isolation transformers at the end of the chain.
Harmonics can then interact with other components on the system creating a mess of circulating frequencies with abandon. Some isolating type Power Conditioners use EMC/RFI filters to separate out higher frequencies of noise which is fine, but they don’t filter or shunt out AC harmonics, 3rd, 5th, 7th and so on. It is with difficulty to design such a filter, since the magnitude of the filter depends on the level of harmonics and the impedance of the supply. Over correcting for harmonics and you end up with filtering your neighbour’s harmonics and under, well it’s an effort, but doesn’t hit the nail on the head.
The measurements I took with the oscilloscope are at the amplifier, not a neutral, I don’t see the relevance of your reference. The earth reference is the mid point of the balanced system, it’s the frame of reference and differs from the protective earth at the main switchboard by impedance of the cable only. The neutral is isolated from the audio system by a) an isolation transformer that lifts the neutral above ground, and b) by the Equitech device. There is a GFCI (RCD) after the Equitech output, and yes, it is a two-pole device.
The earth connection is the same and unbroken back to the panel as required by codes and that’s fine. All the audio components in my system have hard earthed connections to the cases. Currently am working to replace the shielded power cables with the shield at one end to shield at both ends to further improve noise channelling to the Equitech.
The “only” 10db in noise reduction quoted by Bill Whitlock for balanced power supplies is most likely true iff a standard 60-0-60 industrial transformer maybe with 3-5% or worse regulation is used. I know this because I bought one years ago to run 120V equipment, and made the same measurement at the amplifier to ground and the reduction in noise was not as dramatic compared with the Equitech design. Symmetry of the secondary voltages is important to maintain the correct source for balanced AC and to ensure that harmonics are shunted and cancelled. This can be achieved either by choice of magnetic in the core, more windings, better overlay/bifilar windings, insulation materials, that’s all up to the transformer designer to get right.
The value of 400mV versus 7.6nV is not value enough for noise reduction?
Here’s a drawing of my current home system, omitted breakers/fuses and other bits and pieces for clarity.
So do the smaller Equitech's use the same technology, yes they do. The larger they are, the heavier they get. The 1kVA Equitech unit is 60lbs, of which maybe 5lbs is the chassis, switches and the like. The remainder of 55lb is the transformer alone. An off the shelf 1kVA transformer is about 12lb, the extra 43lb weight is the copper and steel to improve the regulation, that's what's needed to obtain that symmetry. As a bonus, overloads are easier to handle, but more importantly, the inrush current to the Equitech is less than rated normal line current. That feature for a toroidal transformer without soft power networks or NTC devices has some thought behind it.
You must have written this with a grin? OK. Far as I am aware, music (audio signals) are alternating peaks of voltage in a given time period. It is an AC waveform, complex but still AC. What comes out of the wall is a much larger AC waveform, it is still AC and obeys the same rules when it comes into contact with resistance, inductance and capacitance, from 0.1fV to 10,000kV.
Noise is what sits on top of either waveform, or is buried deep within, it is made up frequencies (yes AC types) that are unwanted. It is our concerted effort to identify a) where the noise comes from all sources -leave no stone unturned and from there b) to try reduce or eliminate that noise.
With our music source coming from a computer, sources of noise open up a minefield, but the principles of containment still apply the same way.
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I would also be very interested to know if the Q boxes deliver the same clean balanced power as the large Equitech units.
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