Tube Amp for Martin Logan Speakers


Hi, I love tube sound through my Martin Logan Aerius-i fronts and Cinema-i center. I currently have a Butler 5150 which is a hybrid, but it busted on me and would cost $700 to fix. I've had china stereo tube amps that were pretty good and gave true tube sound, but not enough drive for higher volumes. I live in condo, so not like I can blast music anyways but still. I got the Butler because I wanted 5 channel tube sound for home theatre (The piercing sound from my Denon 3801 receiver was not pleasant to my ears). It appears there are only three multi-channel tube amps around, from Mcintosh, Butler 5150, and Dared DV-6C. The latter two are hybrids, and the last one was one of the worst tube amps i've ever heard. I have no clue why 6Moons gave the Dared a 2010 award, but maybe it's because it produces only 65W.

So since multichannel tube amps are hard to come by, and they tend to be hybrid, I was thinking maybe it would be best to get three true tube monoblocks to power my fronts. Thing is I wonder if they will be underpowered for my speakers, and not sure which ones are decent for the price. Maybe China made ones would suffice, and they still go for pretty expensive price. I'm wondering if anybody knows of a decent powerful tube monoblock that is affordable, because I can't pay $3000 per block. or maybe best to just repair my Butler. Thing is, I'm not confident that it is reliable. The tubes are soldered in which is weird, and i've taken it to a couple repair guys who both said that the design is not good, because it's very tight inside and more susceptible to being fried from DC voltage areas. it's too sensitive.

Any suggestions for tube monoblocks, even if china made ones? the holy grail for me would be Mcintosh tube amp, but they are hard to come by. Thanks.

smurfmand70

Showing 1 response by pryso

This is for Ralph, since I'm quoting him. But any others are welcome to jump on it as well.

"I am not stating that 4 ohm speakers are bad speakers. I am stating that any amplifier driving them will sound harsher and less detailed as opposed to the same amplifier driving the same speaker that was 8 ohms, were all other matters to be equal."

I admit my knowledge of electronics is very limited, but this raises a question for me. Is the singular impedance rating of any speaker worthwhile or even all that important? Or is a better question what is the impedance plot across a speaker's response range?

I ask this because for many years I owned Duntech speakers which were rated at 4 ohms. However, reviewing Duntech's impedance plot, it dipped close to 2.5 ohms at two points, the most troublesome being between 60 and 80 Hz as I recall. Considering the power called for at that frequency range and the dip below 3 ohms, well, not ever amp rated to drive a 4 ohm load got off easy!

So my sense is to consider the full impedance curve, not just a static number. Maybe that is where "all other matters" are not equal.