SET on JBL Everests - Mouse breeding an elephant?

I did try it when I first set them up, using 275 on top and Mac MC7270 on the bottom.  For some reason, they sounded horrible.  So bad that I had to verify every setting.  Swapped in a Luxman M6000 amp, no joy, so I gave up and went back to using the internals.  I think I need to retry that approach and invest more time in getting the biamping right.  Heckuva lot easier than the nutty idea I had come up with. 

You would be better off unbridging the amps and using one for bass and one for mids and highs.. That would sound better than bridged MC275s believe me.. 50 years with Macs, you don't bridge any of the 225, 240, or 275s without some serious reworks for SQ.. They just don't cut it for me.. or anyone I know.. Loud yes quality no.. Either way vertical or horizontal, The horizontal is better.  The channel load is more equal.

Still better off with SS for bass management.. JBLs use to be wired different to.. because of the JBL driver phase shift.. I like um... one of my all time favorites.. JBLs, Especially the Everest series.

Regards

“Still better off with SS for bass management.“


I got rid of my old 7270 but I have a 452 that I could use for the bottoms, a single 275 for the tops, then put the other 275s on the block.  I have an idle 4350 that got displaced by the Everests, and I had managed to get it dialed in when I first set it up.  Hopefully, I can manage to do it again.  Anyone have experience with biamping the 67000?

Impedance phase angles are large at low frequencies, though, so the EPDR (equivalent peak dissipation resistance) drops to a minimum of 2.0ohm at 72Hz, and at the other end of the audible spectrum to 2.1ohm at 18.6kHz. So the DD67000 is far from being a testing amplifier load, but it isn’t a pussy cat.

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You want a serious amp. 2.1 ohm load will heat up an amp in a heart beat.. The question is how much of your music is at either end of the scale. 72 hz or 18.6khz, answer not much.

That MC452 and a single MC275. You’ll like that a WHOLE lot more than the current set up.. Maybe not quite the eye candy, but SQ wise a lot better. Get a good set of Mid/High frequency cables for the MC275, maybe OCC/Silver clad ribbons with PTFE covers. Good heavy OCC or OFC copper with PTFE covers for the bass.. 150-250.00 maybe for both pairs.. 3 meter

You already have a good set of amps..... Xtra cables ..

Invest in some good Telefunken signal valves.. 2-300.00 you're WAY better off SQ wise.. Mac and Telefunken valves go together like milk and cookies..

Enjoy..

I agree with the above post. Use the 452 for the woofers and a single 275 for mids and highs. But get an active cross-over (2 - way) to split the signal from your preamp. That way each amp is not having to see a full - range signal and will work better! I have done this myself with a bi - amp system using four speakers.