I am going to experiment bi-amping my mains using 4 of the 5 channels on my 5 channel amp. The 5th channel I will use to power my center. I am not sure whether to get another Adcom (GFA-545) or a Emotiva UPA-200 to power the surrounds. BTW, I listen at low volumes. I have always loved the sound of my Adcoms and don't know if it will be a negative thing using a different brand of power amp for the surrounds. Right now I can get a new UPA-200 for 299.00 vs a used Adcom GFA-545 shipped for about 200.00. The GFA-545 is a Nelson Pass design. The obvious advantage of the Emotiva amp is that it is new versus the Adcom which is about 12 years old. I am going to experiment both with the LsiFX's (4 ohm) and the OMD-5's (6 ohm). What is your opinions?
Here are some spec's on the Adcom.
Adcom GFA-545 Specifications:
Power Output: 100W/channel into 8 Ω, driven channels, with < 0.04% THD Frequency Response: 10 Hz - 20 kHz (-0.25 dB) S/N Ratio: > 110 dB Input Impedance: 100 kΩ Capacitance: 120,000 uf Auxiliary AC outlets: 2 for other peripherals
Post by Dark Ranger on Jan 9, 2013 15:31:43 GMT -5
Based on your post, you might be happier in the long run with the Adcom, especially since you love the sonic signature.
As far as performance goes, either amp will be able to drive the surrounds without trouble. Assuming the used amp is in good condition, I'd probably go with the Adcom if I were in your shoes even though I'm an Emotiva fan. You can keep the same amp brand across all channels, plus you know what it'll sound like. If the brands were reversed (you owned and preferred Emotiva), I would recommend the UPA-200 over the Adcom.
Well, I am an Emotiva fan even though I don't own any of their gear yet (did keep my 40% card from selling the UMC-1 that I won at Emofest). My Adcoms are aging and will have to be replaced sooner or later most likely with Emo amps. I listed the Adcom spec's hoping someone could interpret them against the UPA-200 spec's. The biggest numeric difference between the two amps it seems is in capacitance (whatever that is?). Adcom is 120,000 vs Emotiva 40,000. What difference does capacitance make anyway?
If you have always loved the sound of your Adcoms, instead of buying an Adcom GFA-545, why not a GFA-555II or an Adcom GFA-5800?
BTW, FYI, I'll probably be selling my Adcom GFA-555II and/or an Adcom GFA-5800 soon. I possess the original boxes and packing.
Also, maybe I will be selling my Emotiva XPA-1 monoblock pair w/warranty, too.--It depends since I just received a pair of Emotiva XPR-1s this afternoon but I have not opened the boxes yet.-- I've been busy and I'm waiting for the wife to come home from work.
The reason I considered the 545 was because of my listening levels. The 555, and the 5800 maybe more amp than I need to power two 100w, 5.5" Mirage speakers. Keep me posted on your Adcoms. May reconsider on getting higher power.