Class D and Power Cables


I just put a new pair of W4S Class D monoblocks in my system. So far, I'm very pleased with the result. Now that I know I'm going to listen to them for awhile, I'm starting to consider power cords. But, I started thinking. Does a power cord actually make a difference with these new digital Class D amps? Before I run out and spend a few hunderd on power cables, I was hopoing some of you fellow Agoners could give me some input/experiences. Thanks in advnace.
teletrout
IME I like the Shunyata Venom 3 power cords for Class D type amps like the Red Dragon M1000s.
Best bang for the buck for speaker cable and interconnect
cable is Cabledyne. Square solid core copper or silver wire in an excellent shield. Check out their site and reviews. Performs like the high priced big boy's.
Hi Teletrout. I recommend that that you talk to Matt from Audio Advisor they sell Pangea Power cable
I try one set of Pangea S.E. series it elevate my system
to the next lever, and the best part they are very afordable, believe me the work.
Here is a list of my system Power Amp Audio research DS450 Pre Amp Audio Research LS27 Hedgel DAC HD25
Sony SACD XA5400SE VPI Classic turntable with Aida carthridge by SoundSmith with HDDQute server and Dynaudio speakers Contour. I replaces all the power cables on those unit and love evey bit of it good lock. Juan.
Yep accourding to the theory of the power cords, a small 1m $500 strip can change the performance of hundreds of meters of internal wiring.
Almarg, I agree with you statments, what i recommend
to fellows audiophile is to install a 15 amp separete
circuit line for you A/V sounds system.

good luck Tango.
Since amplifier's power supply draws current in narrow spikes of high amplitude it might be better to plug it into conditioner that has energy storage and filter (huge capacitor and inductor). My amp is placed on Furman Elite PFi 20 and connected with 0.5ft shielded cable. Conditioner can provide 55A of peak current for the amp but peaks drawn by conditioner from the mains are filtered and have much lower amplitude causing only small voltage drops.
When I upgraded my 12/3 romex junction boxed house wiring to a dedicated sub-panel with 20 amp breakers for each run of metal clad 10 g BX, there was a very substantial improvement.

With the old 1972 wiring my class D PS Audio HCA-2 was creating RF that could be heard through a Sony clock radio on the other side of the dwelling. After the upgrade to the volts AC the RF stopped and the performance of the amplifier as well as the rest of the system was noticeably better. The work was done to a raised ranch style home by a licensed electrical contractor for less than $1,100. Clearly the best dollar for dollar system upgrade/tweak to date.

Lastly, I made some DYI 10g shielded power cables. I can't say if was the the larger wire I used or shielding the cables or both, power cables can absolutly make a difference with class D amplifiers. In my experience they don't like silver anything and the more copper the better.
Interesting point, Ralph, which I recall you having mentioned in another thread some time ago.

Conversely, would it follow that if the AC line voltage happens to be GREATER at the location of a particular listener than the line voltage that the amplifier design is optimized for, that (everything else being equal) a relatively narrow gauge power cord that drops significant voltage might provide better results than a very heavy gauge cord?

On the other hand, though, especially in the case of a Class D amp that has very large fluctuations in its current draw as a function of the dynamics of the music, I would imagine that any such benefit might be outweighed by the effects of voltage FLUCTUATIONS resulting from the combination of fluctuating current draw and significant cord resistance.

Audiolab, thanks for your comment. :-)

Best regards,
-- Al
Bifwynne, That was on a 100-watt tube amplifier.

The 2-volt drop is bigger on the secondary side of the power transformer(s).

If you think about it, the heaters cool off a little, the B+ is a little lower, the power tubes are not conducting as hard, the driver circuit can't swing as much voltage. It all adds up.
Thankyou Ralph and Al for a learning exsperience with the post the both of you done, I highly enjoy what the both of you always have to say., cheers
Hi Al, I'm sure external wiring has effects. But we don't get to change that stuff very often, so we also don't get to see how it affects things. The power cable OTOH is something that is easily experienced, and I have been able to correlate audible effects based on some fairly simple measurements.

The other thing I did not mention is voltage drop across the power cord. This can affect any larger amplifier that has a large current draw. I've seen a 2 volt drop across the cord rob an amplifier of nearly 30% of its output power!
Ralph, I don't necessarily disagree, and I would suspect that in general Class D amps may indeed tend to be more sensitive to power cord differences than other classes. But wouldn't the limiting of high frequency high current bursts typically be mainly a function of the house wiring, not the power cord, due to their difference in length, and hence inductance?

Although it would certainly seem conceivable that in some cases other power cord effects, such as voltage losses and coupling of amplifier-generated noise from the power wiring to other parts of the system, could be disproportionately affected by the power cord in comparison to the house wiring.

Best regards,
-- Al
Yes, power cables make a difference, maybe even more so for class D.

If you want to know the theory:

In a conventional power supply (transformer, rectifier, filter capacitors), once the filter caps are charged the amplifier circuit only draws their voltage (stored electrons) down slightly between peaks of the AC mains waveform.

So the rectifiers will only be conducting for a short time on the peaks of the AC power to charge the filter caps. This means that the power cord has to be able to allow very high frequency bursts of current (since the period of time that the rectifiers are conducting might be quite short) through without limiting. This can be quite measurable BTW.

Its hard to imagine that a switching power supply and/or amplifier that relies on high frequency switching won't be affected by this phenomena.

Bottom line is the power cord needs to handle high currents at very high frequencies.

If you encounter anyone who says power cords don't make a difference, direct them to this post.
Yes, AC cables make a difference. Also, start thinking about replacing the fuses with audiophile ones. I did that with my ST-500 and it was some of the better $50 I've spend on audio.
Dear Teletrout I have an Audio Research LS 27 and a class D DS450 power amp. I replaced the power cords on both units with the Pangea the 14SE or the 7SE you will not believe the improvement. Please call Audio Advisor and talk to Mat, he will guide you and tell
what you need good luck Juan.
I use the Triode Wire 7 plus on my W4S MC Mini-7 with great results. Really opened it up!
Thanks everyone for all the grea input Now it's just a matter of which one to pruchase.
This is probably an obvious answer. Why not call W4S and ask Clint or EJ? If you like the amp I'm sure they will give you a straight answer.
I have tried Clarus Crimson power cord on both Bel Canto and Jeff Rowland class D amps with amazing results.
Most of aftermarket cords are made the way they divert the sound and color it to make sure that consumer hears differences. They've been introduced into high definition audio as another layer of brainwash and source of ez money.
It might depend on design of power supply. Some class D amps have straight linear PS while others (like mine) have switchers and some have switchers with power factor module. The most sensitive to power cable is perhaps linear power supply. Switching supply is less sensitive since it is regulated while Power Factor correcting type like Bel Canto Ref1000v2 have additional bank of capacitors minimizing short current spikes - a way that power supply normally takes energy from mains. All this is only my guess and I suspect that any amp can take advantage of better power cable. It is only to what extend.

Hifial is absolutely right - class D is analog. Outside it presents itself as as normal amplifier with about 1% of switching noise that is not audible but inside it operates on principle of Pulse Width Modulation (duty cycle of constant voltage square wave converted to average value of voltage). What is hard to understand is that duty cycle and not the voltage is analogous quantity (it is continuous without discrete steps)
Yes Indeed! I just bought a 6 ft pr of Cullen Crossover PC's.
Never heard my tube amp sound so good. music comes from a "black" dead quite background right out of the box.
Better than my Pangea 9, Zu, Harmonic Tech 11's, Acoustic Zen Tsunami and MAC HC . Not by a little either.
I own a pair of Red Dragon M-500 Class D amps. The sound of the amps was greatly improved all across the board when I started using the Lessloss DFPC power cords. It was a night and day change for the better (for me and my tastes)
I also have a Audio Research 150.2 Class T (Tripath) Amp in another system and I replaced the stock cord with the Lessloss DFPC Signature Power Cord and again the sound and performance of the amp improved tremendously. The improvements that these cords made are not subtle. Now when I used either of these cords on my Tube amps (Quicksilver V4's) the results were a different story. I much preferred the stock cords. That holds true for my tube preamp from ARC (SP16).It seems to me that it's all about synergy with a certain product so if you can, try before you buy. In my experience the Lessloss cords worked miracles on the SS Class D and Class T amps but not so much on most everything else I tried them on, including a DAC (Benchmark DAC 1).Some products when mated with other products really click for the better, and only your ears can decide what sounds best to you. These aftermarket power cords definitely do something but it might not be something that you like. Good luck in your search for the right PC for your amps.
Teletrout, I must correct you on part of your post.

"Does a power cord actually make a difference with these new digital Class D amps?"

Class D Amps ARE NOT DIGITAL. They are analog. The D has nothing to do with them being digital.

As far as power cords go for Class D amps. They can make a difference. It depends on the amp and the power cord.

Merrill Audio includes a power cord that they know will work well with and show how great their amp can sound. But there are other power cords that should bring even better sound to Merrill Audio Amps. Also there are several others that have included a quality power cord with their amps.

And as Plato mentions depending on the rest of your system and tastes you might like one cord over another.

But you still need to find a power cord that works well with your amp, as some will just rob the life out of it.
Why not try Wyred's own Ultra Power Cable? A 1 meter cord is 119.00 and a 1.5 meter cord is only 139.00. Plus, it's the cord that Wyred recommends for it's products. You really have nothing to lose as you can always sell it here for almost what you paid for it.
Absolutely, they all sound different... some are brighter, some are darker, some have more bass and/or a better midrange. So the "perfect cord" for one system/amplifier might not be a good match for another. That's what makes it tricky.

If you like a warm sweet sound with good bass the Mojo Audio Enigma series cords worked well for me when I owned the W4S STI-500 amp. Happy Hunting.
My experience with the d-Sonic amps I bought early this year is that they are the most grateful equipment I have yet encountered. Nearly everything i did to or for them paid out in improvements in sound. They improved substantially when given better cables. I started out with diamondback platinums, a decent entry level cord, but they really came into their own when I installed pS-Audio's former TOL Pc he extreme SC that retailed at about $1000/meter. These can be found here on agon used for under 400 now. They also performed nicely with an older pair of Synergistics research X2 Master couplers.

FWIW, I got the biggest improvement in the amps' sound quality by putting them up on isolation platforms. I got a huge return for around $200. Because they are so small, they only need small maple blocks ($90 at dawnsplatforms) and two sets of mapleshade isolation blocks ($50) and some used brass footers from the web ($60) made a bigger difference than going from the diamonbacks to the PS Audio power cords.