LOOKING AT A 1100 ACTIVE 5.4 SYSTEM.
WHAT AMPS ARE OWNERS USING WITH THESE SPEAKERS?
WOULD CLASS A MAKE A DIFFERENCE WITH THEM?
ANY RECOMMENDATIONS APPRECIATED!
Tom, the major differences between the Axiom Class D amps and Class A amps would be cost, power consumption (efficiency), THD+N and S/N (signal to noise ratio). Compare those and you may also want to talk with Axiom about this for their opinion.
Generally speaking Class A design is the least efficient but has the highest sound fidelity. Class D has the highest efficiency but isn't quite as high-fidelity. Again, generally speaking.
Tom - most are using Axiom's own amps, which work very well. I have 10 channels of ADA-1500's ... others have ADA-1000's (which I tested, and they were excellent) and ADA-1250's.
The options are almost endless within Axiom's own amps, including a monobloc version of the ADA-1500.
For value, Axiom also does special deals when combining their amps with the Active LFR-1100's.
Other options outside Axiom can also work great - the speakers are pretty efficient.
Do you have a budget in mind? What is your room size?
Thank you ALL! & sorry for slow response. I am building a new house with a 10,000 FT3 octogonal common room. Speakers can be up to 18 ft apart. F/R width and 20ftF/R Length if that makes sense.
System will be 4 lfr11A's and four ep800 subs & a 180 (or 1100 Center)
Looking at the 1100A impedance graph they dip to 3.2 ohms.
Looking at good used 5ch amps...names like Krell, Plinius, and a few others ---all class A and double to at least 2 ohms -with extra large torroid's and microfarad storage
Amps can be directly below speakers - basement -in a low volume LVAC system for in-house heat utilization and within 3 ft of speakers.
Just not sure if Class A matters that much with the Active 5- DSP Axiom has with the speaker system.
System will be controlled by either: Casablanca 4a or Trinnov 16and Dirac.
Isotec 150A wall unit for power - 220V
Thanks again for any responses.
18' between front speakers is an awful long way. Is your listening spot 18" from each speaker?
If you want used amps, you may want to consider the mighty Yamaha M-80 or M-85 amps. Continuous Power Per channel both channels driven is 250 W into 8 ohms - (0.003% THD), 290 W into 6 ohms - (0.007% THD), 330W into 4 ohms - (0.02% THD) dynamic into power 8 ohms - 380W, into 4 ohms - 650W, stable to 2 ohms. If you want, you can get 30W per channel in pure class A. The monster Yamaha is a very nice sounding solid state amplifier. I had 2 of mine recapped with 105C 5% caps and they sound great. The M-80 is not bridgeable.
Of course, if you're thinking of LFR1100 Actives, you will need 5 channels of amplification per speaker.
Tom, 18 feet is a width I've never tried. I've gone 13 feet with all the Axioms you see in my signature (except on-walls), with great results. The LFR1100A manual suggests 6 to 12 feet. Talk with Axiom about that.
As for amps, you may also want to look at Bryston. You'll need ten 28B cubed per LFR1100A. https://bryston.com/amplifiers/28b3/
GOOD DAY! AND THANKS AGAIN. 18 FT IS THE MAX DISTANCE AVAILABLE THAT PUT THE LISTENER AT 9 FT-MIDDLE. CAN BE NO LESS THAN 10FT
THANKS FOR YAM AND BRYSTON SUGGESTIONS ALSO. BRYSTON NOT CLASS A AS PER MY THINKING BUT HAVEN'T HEARD FROM ANYONE THAT HAS/IS TRYING DIFFERENT AMPS W/ THE 1100A'S.
I have a Pioneer A9 stereo receiver. There have been a few different versions of it. I have the dual mono, with dual toroids and 10,000uF per side. The rating is 70W/channel average into 4 Ohms. It is class AB. I use this to power the M2OW which I can listen to for hours with their broad, deep soundstage, excellent imaging and vanishingly low distortion.
Anyway, I used this receiver to power the active 1100 woofers. The ADA-1000-8 was powering the remaining 8 channels. I had to adjust the volume of the Pioneer to match the ADA because the gain structures are different. I was sitting 10 feet away and could bring the actives to head-splitting levels without the Pioneer giving out. I was not using a sub.
You won't need high average power for the actives particularly since you'll be using subs. You need peak (dynamic) power, low noise and low distortion. The low distortion is the easy part.
Yamaha M80 can be set for pure class A 30W per channel.
What is the dynamic capability of the Yammie in Class A?
No specs on Pure Class A operation, except it is rated at 30 wpc in pure Class A. I figure it's into 8 ohms, but dunno.
Sounds pretty good!
From Yamaha M80 manual:
Dynamic Power 1kHz 8 ohms 380 wpc; 6 ohms 480 wpc; 4 ohms 640 wpc; 2 ohms 850 wpc
Signal to Noise Ratio (IHF-A-Network) Main in shorted, 5.1 kohms 127dB/119dB
I don’t see a slew rate spec
Damping Factor (Speaker A, 1kHz, 8ohms) 250
AND from Stereo Review 1984:
+0, -0.3dB from 5 to 20,000 Hz;
-3dB at 80,000 Hz
1,000-Hz output power at clipping:
332 watts into 8 ohms,
462 watts into 4 ohms,
612 watts into 2 ohms
Dynamic Power output (20 milliseconds duration):
486 watts into 8 ohms,
787 watts into 4 ohms,
1045 watts into 2 ohms,
1.23dB (8 ohms)
1.46dB (4 ohms)
20-20,000Hz, 250 watts output: 0.006%
Sensitivity: (for 1-watt output):
Signal-to-noise ratio (referred to 1 watts, A-weighted):
Greater than measurement limit of 25
**Specs and article credit goes to one the best magazine of all time, Stereo Review, November 1984. Stereo Review is now Sound & Vision Magazine
Philip, I currently have a bit of an Axiom temple going at my place. Bequeathing that Yammie to me would permanently memorialize your gift with your nameplate made out of the finest Valencia Vinyl.
Haha! That's funny. I have 2. Used 1 to drive the Thiel CS3.6s, but once I used the XLR connections in the Cary, couldn't use the RCAs from the M80 anymore.