wanted to buy: Adcom GFA 565

[ESM]

i am in the market for an Adcom gfa 565, or an amp that resembles it in high current abilities.


background:
i am trying to match the amp to the speaker. i have a ML Stage that i bought off craigslist some time ago (cheap). i am running it off  a Rotel but fear that the power hungry MLS may be pushing my HT receiver. the load is rated at 4-8ohm according to ML however i have read where it drops significantly, some have stated down to 2 ohms....


thanks for your time,

[Slim-Shaddy]

Just an idea... I ran a Carver TFM 25 all night loudly at 2 ohms avg per channel and it never whimpered. That was just for bass, so I don't know how it would do for full range, but you could get into one cheaper than the 565 and just run 1 channel... or try it mono and see if it goes into protect.

[OldiesButGoodies]

The Sunfire 300x2 is stable to 2 ohms (Anders or Tom please verify),  as I recall.  Handled my ML Sequel IIs just fine for hours. I have one for sale.  I also I have an Adcom 555II for sale but I would not vouch for that amp driving MLs,  it  is happier 4-8 ohms.

OBG

[schwarcw]

Just an idea... I ran a Carver TFM 25 all night loudly at 2 ohms avg per channel and it never whimpered. That was just for bass, so I don't know how it would do for full range, but you could get into one cheaper than the 565 and just run 1 channel... or try it mono and see if it goes into protect.

Most amplifiers when bridged to mono will only be good for 8 ohms.  The Carver may be different but usually they get angry    in mono with less than 8 ohms.

[OldiesButGoodies]

Agree.  The Adcom 555ii I own gets 'angry' quickly,  and sounds like monkey ass compared to not bridged (same with several bridgeable Parasounds and NAD amps I have owned - seems like manufacturers add this as a feature they can brag about in spec sheets but not meant to really be used by anyone serious about sound).  I have yet to find a stereo amp that sounds good bridged.  I guess if such an amp is used to drive a subwoofer that could mask the issues that become obvious at full range while having a positive impact on actual bass output.

[MacGeek]

Any MAC amp with autoformers in the output can handle just about any impedance all day long in bridged mono mode.  Some of the less recent models came in a utility configuration (with out glass fronts and meters) and can be had for reasonable prices.  Some of their direct coupled amps exhibit the same "angryness" Carl described.

[schwarcw]

There are amps out there that are stable when bridged, but they are usually more robust (read expensive).  Some Mac amps as Klaus noted can handle it.  Audio equipment companies offer monoblocks for a reason.  I wouldn't bridge any amp except for maybe driving a subwoofer.

[MacGeek]

If the speakers can be bi-amped (or tri-amped), another approach is to run the amp in a bridged, mono parallel mode, sending one channel of the amp to the high frequency drivers and the other to the woofers.  Any decent amp should be able to handle lower resistance in each of the parallel channels that might occur. 

I have my rig set up using a bridged mono parallel mode to bi-amped speakers.  In addition to the power increase available for each channel (3 db at twice the power), there is an advantage over a pure mono bridged mode (or a mono block amp of the same power rating), in that the low frequency driver will not rob power from the highs.  While the total power per channel is the same as in a traditional bridged mode, there is more headroom for the high frequencies, virtually eliminating compression.  My ears crap out long before the amps or speakers do.  Of course, this assumes there is a reasonable amount of power available from the amp to begin with.

[ESM]

I don't think a Mac amp is in the budget. shootin that one down, but not out..
i have a carver M1.0 that i was going to use as a single channel and leave the other channel idle but i have been told that is not the best route. still may go there if i can find one that is reasonable and stable down to the lower depths. (and i kinda like the old girl M1.0t mated to her counterpart C-1, i don't necessarily want to break up that set.
i have been told and have read that bridging is a bad idea when pushing heavy loads, 8 ohms is ok.
 but 4 ohms , dropping to 2.7 and maybe lower not so smart. magic smoke time

as this is a center channel, unless i gut her and reconfigure the crossover , there will be no bi/tri/ amping going on, as there is one set of posts.
however this may not be a bad idea...i'll have to look into the crossover online.

i was told by tom himself (thanks Tom) that the GFA 565 is what i need. however we were looking at reasonable auction prices that had ended, not the prices people are asking now. figures.

thanks for all your replies, i am listening and researching all of your ideas with high expectations..

any thoughts on a crown Micro tech 600. price seems ok and specs say shes stable to 2 ohms.. using it with one channel idle that is.

[ESM]

any thoughts on a CARVER A500X?

A-500x SPECIFICATIONS
Frequency Repsonse: 20-20kHz +0,-0.2dB
Power Output: FTC 20hz-20khz
8ohm 250 watts per channel
4ohm 400 watts per channel
2ohm 750 watts per channel

i am thinking it has potential but would love to hear your thoughts..

running it as a single channel, not bridged as discussed earlier

[ESM]

any thoughts on the Roksan Caspian M1 ?

[ESM]

well i purchased the Meitner MTR-101.
it is a monoblock amp that is rated class A to 100w.
a link to Ed's page     http://www.museatex.com/mtr.htm
she is driving my ML stage with ease.
sounds great.

let me know if you or someone you know has used this amp.
i am also very curious about his upgrade. if you have had this upgrade done let me know what you think.
thanks   

[OldiesButGoodies]

Very nice.  It it can make the MLs move its got the right stuff.    Your electric bill may go up a bit,  power down when not in use!

[ESM]

Thanks OBG.
Spoke with John of Meitner the other day via email, said it was a cool $750 for a pair to go under the knife for a total makeover. i have a few things on the list before that one but i may give in a year or so.