simply saying, your amp will be stable with these cables. Most-likely SET amp(s) will not be stable with them.
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If your amp is of a wide-bandwidth design, it would probably be wise to use zobel networks with these cables. Keep in mind that an amp can become "partially unstable" and not go into continual oscillation. Severe cases will manifest themselves as an extreme amount of heat build-up, the smell of smoldering electronics, protection circuitry kicking in, etc... Then again, most wide bandwidth amps don't use protection circuitry due to the negative sonic impact that go along with such circuitry. Sean
I am not that familiar with McCormack products although i have a lot of respect for what i've seen in terms of design.
As to the MI-3's, these sound different to me than the MI-2's. You will have to try them in your system and see if you like them. Personally, i like the MI-2's a little better. The 3's are a little more bottom heavy to me, which does not compliment my already "weighty" sounding speakers. However, given that you are running Thiel's, which many find to be somewhat bright, this might work perfectly for you. Either way, if you don't like the 3's, give the 2's a try. If you don't like the 3's nor the 2's, you don't like Goertz products then. : )
Good luck and i hope they work well for you : ) Sean
Pops, you are lucky. Several of my amps have no protection circuitry in them by design. If i forget to attach the zobel networks, up in smoke they'll go. I caught one screw-up as i could literally smell the amp "cooking". This was only after about 1/2 an hour or so of idling after being connected and powered up. Would have been an expensive "oversight" if i had left the house for a bit or something else came up. That is why i try to stress the importance of using the Zobel's if unsure. As in your case, you might not have tell-tale signs instantly, but that doesn't mean that the amplifier likes it long term. Better to be safe than sorry. Sean
The factory supplied Goertz networks are designed to come into play at 160 KHz. As you might guess, this is WAY out of our hearing range of what is supposedly 20 KHz. Since i only know of one speaker that actually could make it out to 100 KHz, i don't think that we have to worry about the results being audible. Shoot, many components and most sources are way down by the time they get to 100 KHz let alone 150+ KHz. In fact, some are specifically designed for very limited bandwidth. Sean
Just another note on goertz networks - use them! My amp was idleing last night and when I went downstairs to shut down I noticed it was fairly hot, like it is when I use it for an extended time or my Thiels put it to task. I checked connections and 1 of the networks had slipped off a binding post from moving the speaker. These are fantastic cables. However, it's hard to believe only 1% of all amps oscillate with these - I use a Classe and fortunately they are very stable and have a protection circuit.
Now you know why i stress the fact that people should use these Pops, even if they don't think that they need them. Out of curiosity, how do you have the networks connected to the speaker binding posts ?
What i've found to work well is to use the clamping action of the binding post on the cable's spades or the bare end of the wire. I then install the zobel's into the banana jacks courtesy of banana plugs that i've attached to them. They remain very stable this way and do not interfere with the "clamping action" or quality of connection between the posts and the speaker cables. One need not use "high grade" bananas for this purpose, just make sure that you have a good connection from the zobel to the banana plug and from the banana plug to the binding post jack.
Hope this helps some of you out. Sean
I am investigating this one for myself. Thanks for bringing this up! I am speaking with Classe and Innersound right now.
IF you look at their FAQ section - http://www.alphacore.com/mifaq.html - it also states: the situation described in the above does not occur with electrostatic speakers or with tube amplifiers containing output transformers.
Angela, i forgot about the speakers that you were running during our email conversation. If you remember though, i did mention that you might not be having a problem due to the specific speaker load that you had on the amp.
The reason that the output transformer "nulls" the "problematic effect" of the cables in these situations is due to the fact that it introduces inductance into the circuit. The inductance from the transformer somewhat counters the capacitance of the cables and presents a more benign load. You are probably okay with what you have, but it wouldn't hurt to find out for yourself. Sean
one 'mo time, in plain english, my friend :-}
just teasin'. I have the service manager at Classe looking into for me and have fired off the detail to Roger at Innersound as well. This is the kind of stuff that floats Roger's boat, so I am sure that he will have a wealth of information, too. I love the opportunity to learn all of this. thanks for your help by email, Sean.
-aj aka Telly (wink wink)