Directionality for Alphacore Goertz MI 2 cable?


I am in the process of auditioning a pair of Alphacore Goertz MI(2) Veracity speaker cable. From what I have read these do not require much burn-in time, but the highs are sounding awfully bright and grainy. I've got Paradigm Studio Reference 20 v.2 monitors which have a metal tweeter (bright). But I can't believe the Alphacore cable could be quite this bad. There are no directional markings on the cables, no arrows that is. One end of each cable is labeled with the Alphacore name--is this to be considered the amp end or the speaker end? There was no instruction sheet and the packaging does not mention directionality. Can anyone advise?
salby6
There is no directionality on this speaker cable. I'm not sure what may be causing the bright, grainy highs you say you are experiencing, but it's possible that there may be an impedance imbalance resulting from an amp/cable/speaker mismatch. The Goertz speaker cables have very low impedance -- the MI2 has an impedance of about 2.4 ohms. I am currently using MI2 cables in my system and have been very pleased with them, so I hope one of our Audiogon guys with an electronics background can help.
Hi Salby,

Goertz offers free parts for a Zoble upon request, due to the low impedence and very high capacitance Goertz cables can cause a multiplicity of problems with some amps. Zobles should clear all that up, if this is your problem. Goertz are actually one of the more neutral cables out there, so if you are hearing it, it likely is there to be heard. I know some cables are very dark and actually act like a sponge, soaking up the sound so to speak...

Best Regards,

Lou
Salby, I am using those cables between classe and Thiel 3.6's - I am getting no brightness at all, in fact until recently I was using all silver interconnects and still no brightness. My experience with these cables is the most neutral sound I've had in my system, with a very slight bloom and smooth highs. No burn-in required and no directionality. Could they be exposing something upstream?
The response by Lou is correct. Try the Zobel network
which Alpha-core will provide free upon request. Some
amplifiers with high negative feedback become unstable
with Goertz cables, and the Zobel will fix the problem.

I'm using MI-2 cables with a Mark Levinson 27.5 with
very pleasing results.
I am using those cables with a Bryston 9B driving 20 v.2 and 60 v.2 and not having any special problems with highlighting/brightness. What amp do you have?
Hi Jvogt,

Actually, it is low negative feedback, broadband amps, like Stasis and Spectral that have issues with Goertz cables. I have heard that Spectrals are so susceptible to this that they will not guarantee their gear unless you use their MIT cables, which are zobeled. Global feedback makes an amp more stable, but that comes at a price, as they do not sound as good. Nelson Pass has something on this at his site, I think it is under the article on cascode amps. The more feedback, the more you kill the highs, which kills air, etc...
Goertz supplies Zobels with EVERY set of speaker cables that they sell or supply to dealers. If you did not get the Zobel network, contact your dealer and raise hell. Unless you know for sure that your amplifier will not react to a high capacitance load, you should ALWAYS use the factory supplied Zobel network. I would not consider the use of the Zobel to be "optional" in 99% of the installations out there. The factory supplied Zobels are designed to stabilize the load that the amp sees starting at appr 160 KHz, so it will not affect the sonics of the system, only the stability of the amp.

As to hearing bright and grainy, that sounds like your amplifier crying out for help. Without the Zobel network and depending on the design of your individual amplifier, you may have what is effectively a dead short to the amplifier at VERY high frequencies. This can result in smearing and distortion of the signal in-band. Take the Goertz out of your system RIGHT NOW before you run into major problems OR install the Zobel networks pronto. If you do not do this, you are looking at blowing the outputs of your amplifier and potentially your speakers.

As to the sonic characteristics that you hear after the Zobel's have been put into the system, you are hearing what your system really sounds like. Goertz cables do not suffer from skin effect, limited bandwidth, high series resistance, etc... As such, it will lay the soul of your system out before you without mercy. At the same time, it will not introduce sonics of its' own because of the aforementioned electrical characteristics. If your system still sounds bright and grainy, time to start looking for other sources of the offensive noise that you can hear.

Out of curiosity, what length of MI-2 are you currently using ?

For the record, it is not a matter of an amp using large quantities of negative feedback that can cause instability to occur with highly capacitive cables. It has to do with how the feedback network is designed and the bandwidth of the amp.

Thanks to all for the posts on this thread. I will install the Zobel's this afternoon.

The MI(2)'s I am auditioning are 6 feet. My amp is an Arcam Alpha 8R which is a warm amp and have had no problems to the present with Mapleshade Double Golden Helix or Audioquest Type 4+.
Right on Lou !!! Slow amps with limited bandwidth and poor rise time using gobs of negative feedback have nothing to fear from these cables. Then again, amps of this nature are not typically found in audiophile systems nowadays. This is due to the poor sonic characteristics that they introduce into the system ( lack of air & high frequency detail, veiled midrange, etc.. ). That is the reason why i recommend using the Zobel's for the mass majority of installations. Most SS amps have come a long way since the 1970's in terms of the spec's ( lower grade parts and circuitry with greater error correction ) vs sonics ( faster & wider bandwidth circuitry with better quality of parts ) approach to building and designing SS amps.

Bare in mind that even if an amp can't deliver rull rated power at very high frequencies, that will NOT keep it from "trying" to deliver power at those ultrasonic frequencies. Since the amp is trying so hard to reproduce power at out of band frequencies, the signal that is being reproduced in-band is compromised. As such, the Zobel's may even be beneficial to amps that are not normally thought of as being "fast" or of limited bandwidth design. Sean
>
After installing the "protection" for my amp, I am disappointed to say that the Alphacore Goertz MI(2)'s are still too bright, perhaps too thin in my system. I know from experience that my Paradigms can be painfully bright on the highs, so I am going to look further for a cable solution and return the Goertz MI(2) to the manufacturer.
Hi Salby,

You know that what you are really telling us is that the Goertz cables do not compensate for other system issues... I agree that changing cables is the least expensive way to go, but it really is not the right way to go... I think the Paradigms may be a little tweaked for HT, but I have power the 100's with good gear with reasonable results...

Best Regards,

Lou
Most people that i know complain of the copper based Goertz sounding warm and round, not lean and bright. Then again, maybe you're having the type of results that i did with AP Oval 9's. My results seem to contrast those of the mass majority. If that is the case, the Oval 9's may be just what you are looking for. Sean
>