what amp to use with Renaissance 15a

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Hi Robert. I sounds like you have an ESL C18. Just wondering what kind of centre channel speaker did you use before you installed the ESL C18 and whether there was a significant imporvement in sound. Are you driving the ESL C18 with your AV receiver or a mono power amplifier connected to your AV receiver. Appreciate your comments. Thanks.
Prior I was using a Martin Logan Theater i. I am powering the Focus C18 with an Emotiva monoblock running off of my Marantz Receiver.
https://emotiva.com/products/hc-1
I originally was powering my theater i with the Marantz. Then I upgraded to the C18 and the sound was very much improved! The main thing I noticed was improved clarity of dialog in movies and TV. The theater made it hard to understand speech. I sold it at my local store and got the C18.
After a few months I decided to upgrade again and get that Emotiva monoblock. I'm glad I did because it was another improvement. The improvement wasn't quite as great as the speaker upgrade, but it was very worthwhile.
The old theater i was all original except for a new woofer I replaced.
 
I to have c18 also what big difference over ML ESL poweredby Anthem soon to be powered by Emotiva
 
I powered my ML15A by Mcintosh MC611, recently upgraded to MC1.25KW and starting from now I feel full control of speakers by amplifier with zero compression, real life sound indeed. I am curious of opinion other guys powering 15A by MC1.25KW, especially in terms of color of the sound, currently my seems to be too bright in compare to MC611 but perhaps it is matter of quite new amplifier and time required to burn-in or type of cables to match expectations.
 
I powered my ML15A by Mcintosh MC611, recently upgraded to MC1.25KW and starting from now I feel full control of speakers by amplifier with zero compression, real life sound indeed. I am curious of opinion other guys powering 15A by MC1.25KW, especially in terms of color of the sound, currently my seems to be too bright in compare to MC611 but perhaps it is matter of quite new amplifier and time required to burn-in or type of cables to match expectations.
I can't give an opinion with regards to these amps with 15A speakers. But, in the specs for both amps, other than the power difference the only spec I see that might have an impact on the sound is the Dynamic Headroom, which is higher on the MC611.

I'm not one who lends a lot of credence to solid state burn-in except for as it relates to capacitors, which I believe take a little time to like how they've "formed" during the first number of hours. But some of those hours should have been done at the factory already.

Otherwise, it's just down to the power difference which might lend itself to a brighter presentation with more power. Or, maybe a cable moved.
 
Yes, agree with ttocs.
McIntosh is one of those makes that vary from model to model and the variance isn't marginal. I'm not sure what it is, whether it's the auto-formers... unlike most well designed SS gear, where their Output power doubles or triples as impedence swing drops, in the case of Mac this doesn't happen. Due to its Auto-former design, whether this is a good thing or bad thing I don't know. Mac hasn't deviated from this Auto-former design since the kookobas came home, and they continued to use it in every power amplifier design to date.

I've tried 100w Mac amps that couldn't drive my former Maggie's optimally (MG3 5/r) or any of those previous Maggie's I had ranging from MGIIIA to MG20.1's. Then auditioned big Mac's driving the ML Neoliths, those were the MC1200 monoblocks, massive amounts of power but not optimal. Then tried a MC462 on the Ren15a's, fine! I guess the hybrids are easier to handle compared to either full range ribbons or stats.

Then a very good mate of mine here had the mighty Maggie's 30.7's (the one and only 30.7's to arrive in Aus). Drove them with his C53 and MC462, didn't work too well. He sold off the 30.7's and just stuck with his Klipsch triple stacked horns, the Mac amps love those Klipsch horns! He's also using the MC452 and another MC301 for the low end, mighty impressive and massive dynamics, plenty plenty of headroom.

On that very same Neolith system, we tried Pass Labs XA160.8, and Momentum 400's both monoblock design, oh my! What a shift in gear! Totally different league!
Also auditioned at length Pass Labs XS300's and Dan D's Relentless monoblocks driving the Maggie 30.7's, completely different dimension, it's not even funny.

So goes to show that it's definitely not all about watts/ power. It's the high current capacity along with highly stable voltage that drives and controls stats optimally. Yes, power is important but what's the use of all those precious watts... when impedence swing drops to less than 1 Ohm (0.7 Ohms to be exact) and suddenly rises to 20 Ohms in a blink of an eye, those watts aren't going to make it. Current and stable voltages are critical to driving stats and this is where the headroom proves worthy.

Most high powered amplifiers simply don't have very well designed power supplies in the Output stages but on specs they look mighty impressive! This is where they run out of puff, especially on the high notes. And with stats, it's the high notes where the impedence drops to less than 1 Ohm, not the bass. Bass makes the impedence rise to over 20 Ohms in some cases, this is referred to as "Reactive loads" and only very well designed power supplies can handle reactive loads typically found in stats!

Oh! I forgot to mention one particular make that's a phenomenal match with ML stats, apart from the ones mentioned above. The Vitus SS-103, phenomenal!
Awe-inspiring experience.

Cheers and enjoy those fine tunes!
RJ
 
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This was very impressive Chord Ultima 2 with. Neoliths.
1701886554307.jpeg
 
This was very impressive Chord Ultima 2 with. Neoliths.
View attachment 24733
I bet the Chord Ultima 2's sound brilliant. I use Chord Ultima 3's with my 15A's; but I do yearn for the upgrade to Ultima 2.
I'm justifying not upgrading (other than financially) by being unsure if the additional output power (750w RMS into 8 Ohms) would ever get used against (480w RMS into 8 Ohms) bearing in mind the active nature of the 15A's
 
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I bet the Chord Ultima 2's sound brilliant. I use Chord Ultima 3's with my 15A's; but I do yearn for the upgrade to Ultima 2.
I'm justifying not upgrading (other than financially) by being unsure if the additional output power (750w RMS into 8 Ohms) would ever get used against (480w RMS into 8 Ohms) bearing in mind the active nature of the 15A's

And owner of the Neoliths has just ordered ANOTHER two Chords Ultima 2 for bi-amping.
This is what I call, thinking big.
 

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