Bi-wire test - VERY surprising (1 Viewer)

[John Royster]

I wanted to try out bi-wiring my speakers and overall to try out some different speaker cable. The results that follow are VERY surprising and really did shock me in the differences I and my wife heard. Mind you in these test I didn't tell my wife what or if I had done anything but simply asked "describe what you hear."

gear - adcom gcd700 cd player, HK 8800 integrated amp (100x2), Martin Logan reQuest speakers.
Cables - 2 pairs of home depot 12 gauge speaker wire, monster cable (something like 200 bucks way back), audioquest cobalt I believe speaker wire. Keep in mind the speakers are firmly anchored with spikes and 50 lbs of weight on each speaker, they ain't movin'.

We've been accustomed to the audioquest for speaker cable in regular fashion, single pair per speaker and were pretty familiar with the sound. There are some favorite test tracks from Peter Gabriel, Santana and Janet Jackson because the recordings are great and the range of each can really shine depending on the speakers in question.

Audioquest (single pair attached to the high inputs on speakers with jumper in place) - good, smooth bass, clean highs, detailed but somewhat thin sounding, collapsed soundstage, good imaging but confused sometimes.

Monster Cable (single pair attached to the high inputs on speakers with jumper in place) - decent, distorted vocals, didn't have the crispness I'm used to, bass is a tad muddy, soundstage is collapsed between speakers, imaging is poor.

HD cable (dual pairs to each speaker, bi-wired with jumpers removed) - Deep, lots of bass. Bass is tighter and more pronounced. lower midrange and vocals tend to bloom and overpower the highs. Loss of upper highs so much so that we both questioned what happened to some instruments. Lost that "air" of the soundstage. Again, lots of bass, vocals are smoother but at what cost?

HD cable (single pair attached to the high inputs on speakers with jumper in place) - Nice, bass is tight. Great soundstage extending beyond speakers with good depth. vocals are spot on but "maybe" a slight harsh, highs have a good air. imaging very good.

I post this only because I am truly amazed at the difference between the cables/methods. Yes I'll state here that it was quite profound. For now I'm sticking with the home depot single pair.

BUT!!!! Picking a better or worse was somewhat difficult and required switching back and forth and calling the other into the room. We both could accurately (blind I might add) tell what was happening with our favorite tracks. The bi-wire seemed to drown out the highs with midrange and bass so that one was out. We prefered the soundstage and richness of the HD single pair.

Go figure. I'm a bit surprised myself. Now I'm not going to try and explain it, but that's what we heard both being amateur musicians. Heck, it was worth me spending 15 bucks on cable just to try. We are convinced beyond any shadow of a doubt that speaker cables do indeed sound differnt, VERY different. Does an expensive cable sound "better" than a less costly one? Don't know - listen and decide for yourself.

FWIW,
John

 

[Chu Gai]

Interesting John. You do that all in one evening? That's a hybrid electrostat if memory serves me right. Tests are difficult to perform in a blind fashion and I think your inquisitive nature is admirable. If you recall, in what order did you perform the tests? How'd you like to do some more tests and if you've no objection I'd like to outline some scenarios. Were I there, in the land of the Derby, I'd have done the switching, but maybe we can all learn something. Game?

 

[Mark Tranchant]

John - what connection method did you use (bananas, spades, bare wire...)?

I firmly believe that the quality of the connection at each end is far more significant than the difference between two cables of similar gauge and construction.

It'd be interesting to include (blind to the "judge" and at a random point during the test, of course) the same cable twice in your tests, disconnected and reconnected as if it were a new cable being tested.

What impedance are the reQuests?

 

[John Royster]

The requests are nominal 4 ohms but dip to 1.2 ohms. A 4 foot by 2 foot panel with 12" woofer. The speaker manuals says something about "make sure you use speaker cable with no more capacitance the .2f"
You may be on to something about connection methods.
10 foot Monster - banana
10 foot AudioQuest - spade
10 foot Home Depot - bare wire
Chu - The order was audioquest (in place), HD bi-wire, HD single, Monster, HD bi-wire (deciding against this method on the second go around), Monster, HD single, audioquest. over the span of about 3 leisurely hours.
At that point one of us would leave the room while the other switched or didn't switch the HD single and audioquest. 4 out of 4 tries we got it right (2 times each person). Might not be statistically significant but I probably won't be doing this again for a while - 12 gauge bare wire is a total pain to deal with especially with two pairs. I'm gonna let the HD wire break in a while and maybe perform the test again in a month. See if I still DON'T like the bi-wire.
Anyway I am really surprised by the results and to me these weren't subtle differences but then again to most non-freaks it would be considered subtle.
I am even more convinced that "good sound" is very subjective as some really would prefer the enhanced bass of the bi-wire. Too much for me though and it overpowered the logans strengths.
-edit- for a little more info check reQuest manual here:
http://www.martinlogan.com/product_a...s.html#request

 

[DannyL]

i had a similar experience with my martin logan sl3's. i am using an aragon 8008 amp to drive them. originally i was using 16 gauge rat shack cable with a jumper. i later changed to biwiring with the same kind of cable and i noticed an increase in harshness in vocals and a drop in bass output. i later changed to 4 conductor ixos 16 gauge wire, and noticed the same difference between single wire and biwiring. i preferred the single wire with a jumper. i can't explain it.

 

[John Royster]

Thanks danny,
guess the speakers can be finicky about cable. Strange that bi-wiring has a negative effect. Now if I could only audition four pairs of cable in the 300-500 dollar range that work well with martin logans I'd be all set for another test of bi-wire vs. single wire.

 

[Chu Gai]

Electrostatics are a bizarre beast and they present problems to amplifiers and yes even cables due to their bizarre impedance curves which are typically nothing like more conventional systems although I'm sure there are a few whacked out conventionals out there. While in the vast majority of cases that represent mainstream audio such issues are shall we say non-issues, yours is a particularly different situation. Now in all honesty, people who make electrostatics ought to provide their own amp to drive these things and while not familiar with your hk, offhand i'd say i'm surprised it doesn't have issues at such low impedences with tendencies to overheat. If'n I were to be lookin at cables for these babies, i'd be looking to find the cheapest low capacitance cable i could find and i'd keep it short!! I don't have any particular recipes but I'm sure others do and no doubt the web has some stuff on this. However the following does come to mind John since you're of the mind to experiment. I'd look to find the lowest capacitance RG-58 or RG-6 I could (probably means a teflon dielectric) and I'd buy me 40 feet of it (you've got 10 foot spacing it seems) and cut that length into 4's. One cable for the high, one for the low. Understand we're not talking biwiring here, but....Take a look over at Belden and they've a toll free # and i'm sure if you call, they can suggest some reasonable suggestions for you to investigate.
Does this mean I believe cables can make a difference? Well that depends on how you want to spin it. I look at it as electrostatics are whacky speakers (yeah, they can sound nice ) and hence require whacky approaches.
Now if you try this John, I expect a good solid blind test performed by a friend and if you level match, I'll just be in einsteinian heaven. If you want some details please contact me.
BTW John, if you have the impedence curves, send em over would you?

 

[Saurav]

I know someone who uses speaker cables in an interesting way. He has 108dB sensitive speakers and 0.5W amps. He uses 30 or 32 AWG wire as his speaker cable, and uses a length that gives the cable a specific DC resistance (I think around 4 ohms). He's a vastly superior electrical engineer than I am (the amps are his own design, for instance, and he's well respected in the DIY audio community), so I don't profess to understand why he has his system set up this way, it obviously does something to the amp/speaker interaction (besides introducing losses, of course).

Anyway... just thought that people might be interested in knowing that there are schools of thought that differ from "keep it as low resistance/capacitance/inductance as possible". Is this "using a speaker cable as a tone control"? Depends on how you look at it. It's certainly a component in the electrical chain, and you need to factor it in when designing the amp/speaker interface. Seems to make sense to me, and it's definitely a more scientific approach than randomly trying different things and listening for differences. Of course, not everyone has the skill or the knowhow to do this analysis/design.

 

[Chu Gai]

Saurav, to get a 4 ohm net resistance with a 32 gauge wire would require a huge distance. For 28 gauge (which is what i've values for (0.0764 Ohm/ft) he'd be looking at a run of 52 feet...actually 1/2 that if we're considering both legs. but horns don't have bizarre impedence curves and such low ones to boot as do the stats.

 

[brucek]

Saurav,

I know someone who uses speaker cables in an interesting way. He has 108dB sensitive speakers and 0.5W amps. He uses 30 or 32 AWG wire as his speaker cable, and uses a length that gives the cable a specific DC resistance (I think around 4 ohms).

Actually, this is not all that uncommon a practice. As you know the output impedance of most solid state amplifiers is extremely low (in the order of .01-.05 ohms). It is also quite linear and a near perfect voltage source. The non-linearity of the typical speaker is then of little concern with respect to its effect on the frequency response of the "amp & speaker" interface because all the voltage is dropped across the load.
Think how upsetting it would be to this balance if the output impedance of the amplifier was higher or had an extreme frequency dependant output impedance. This would create a voltage divider effect and cause distortion that would not be too different than the "warm" (read distorted) sound that a typical tube amp produces.
You can create this sound easily by placing a large power resistor at the output stage of a solid state amplifier. The power resistor in the order of a few ohms has to dissipate a lot of power though, so some people experiment with super high impedance speaker cables (as your friend has done). This can make for some very interesting distortion that tube lovers seem to like. It also makes cable capacitance important (which we can generally ignore in a cable when using an SS amplifier). You can create some interesting low pass filter effects and their resultant sound with this scheme.
I say why bother. Let your amlifier system be extremely linear and if you want effects, use a processor.........
brucek

 

[Saurav]

Chung,

Yes, you would consider both legs, and 32AWG would have higher resistance than 28, so it doesn't seem like a huge distance.

Bruce,

The amp in question is a tube amp. Maybe he's doing it to distort the sound further, like you said. I don't know.