Tri-amping 3.6R's; what amp for the ribbons?


I currently use a active bi-amp setup w/my 3.6R's. The pre-amp/crossover is a DEQX unit, into a pair of 1000ASP ICEPower amps for the bass panels, and a pair of Bel Canto REF500M's for the mid+ribbon. The crossover is at 200hz, 96db/octave. I'm thinking about moving to a tri-amp setup. Anyone tried this with 3.6R's? Any advice?

What amp for the ribbon, assuming I keep the current amps for the bass & mid? I'm thinking a nice Class A tube amp for the ribbons, but that's just my first instinct.

BTW, I like to crank these speakers LOUD -- as loud as you can go before the panels start farting. I guess ribbons don't require much power, but how low can I go?

Also, I'm concerned about blowing a ribbon -- I have to bypass the fuses, right?
mikeand1
Gahh... typos.

"factor setup" -> "factory setup", meaning Magnepan's own crossover point is 1.7khz between the ribbon and mid panel.
I was just floating the idea that power needed is related to the crossover frequency. 10k was an extreme example and used to illustrate how little power is needed above very high crossover frequencies.
If you had the perfect amount of power per 'way', they'd all redline about the same loudness.

I'd generally stick to the stock crossover points. The folks in WhiteBear Lake spend a bunch of time getting that part right.

You say you like 'd'amps. I have one, too. So, I've got to ask, what do you NOT like about your current setup? Why do you think tubes are the 'cure'?

Several higher power tube amps may do. ARC would be on the short list, since many panel owners use and like them.
Well it's not that I don't like my current setup, just trying to improve on it. I thought there was a big improvement when I moved to a bi-amp setup, and I'm thinking tri-amping would be another step up.

It's my general impression that tube amps are known for their sweet highs.

I totally get the point about less power being necessary for the higher frequencies. I was thinking I wouldn't need anything near 125 watts, even with the crossover at 1.7khz.

And do you really think I'm underpowered with 500w per channel on the mids/ribbons right now? I'm surprised to hear that.

BTW, re the "farting" -- if you turn up the volume loud enough, peaks in bass will cause the panels to "rattle" or emit an unpleasant "thwapping" sound. At that point, I know I have to back off, and that's as loud as I can go.

I'm about to move into a bigger room. Wonder if I'm going to need to upgrade to the 20.1's...
There's a Monarchy SM70 listed for $400 (no relation). Wouldn't hurt too much to try.

Frankly, wrong speakers for the application if you want "farting" level SPL's. Staying dipole/planar, there's Genesis and VMPS (RM60/sub, Supertowers) for that and you can still use the correction of the DEQX and parts of the active crossover (up to 120 Hz high pass for Genesis).
Yes, I believe in the biamp setup, that the 500 is underpowered relative to the 1kw, with the crossover at 200hz.
For 'average' music, the 50:50 point is about 350hz. So, with an even lower crossover it may be 45:55 or perhaps worse.
I'd start by using same amps on the 2 sections....

Now, I'd also measure power output to the panels, even as crude as a DVM. I think the power rails in those amps is what.....80 or 85 volts?
Have you popped a fuse.....yet?

The noise you hear is mylar slap, basically the panel 'bottoming out'. Not recommended, as a general rule.

I don't know that 20.1s play much/any louder. Just move more air and so can couple to a larger room. The NEW 3.7s may have better frequency balance or sound better to whats left of your ears.

If you got the loot to just toss out that you may 'need to upgrade to the 20.1s.....' I'd suggest taking the cash and up-amping to a brace of Pass amps. Don't get me wrong, I, too, have a 'd' amp. And while I'd love to have the pass INT-150, I'm sticking where I'm at and will do room tuning before turning to the bottomless pit of bi/tri amping with the thousands of adjustments.

Keep us posted on your progress.