braminator
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Marsh a400s and Martin Logan SL3
CharlyD
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I had a pair of Sequel II's for several years and can certainly vouch that the electrostatic panel in those beasts is very demanding of its amplifier. Take a look at the impedance curves for the Sequel III review. JA gives a very good analysis of some of the challenges presented to the amplifier through these wildly swinging peaks and valleys. I started off with an Adcom GFA-555, but sopronos just shrieked. The behavior was much more mellow with a Classe (200W?), a bit closer with a Bryston 4B, but I settled on a Proceed Amp2 since it delivered liquid highs with good transient detail and bass control. I bumped into the limits of the Proceed several times however.

The 900 watts consumed by the Marsh when outputting 350 watts is due to losses in the amplifier that will generate heat, not sound. The 350 watts will be delivered to your speakers, but the remainding 550 watts will make the amp a nice space heater. Such perfomance is typical of a class AB amplifier.

I would strongly suggest to require an audition of the amp connected to your SL3s before making a purchase. These speakers are fairly inefficient thus requiring lots of power and present a very complex load requiring a very stable amp design.

braminator
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Thank you very much for the info. I could not pass up the amp as it was a steal. So far it definately opened the speakers up by a huge amount. I was told to let the amp break in for a few days so I guess time will tell.
The amp has rca and xlr's. Would I benefit by getting a preamp with xlrs also? What are the benefits?

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A balanced (XLR connectors) connection between the preamp and amp will offer a much better rejection of any common mode noise than a single-ended connection. In a balaced connection, there are separate conductors for both polarities of the signal. Any noise generated in both conductors (e.g. through RFI/EMI) will be strongly attenuated. If your amp and preamp are separated by more than a few meters, it might be a good idea to use balanced connection. I used balanced connection with the AMP2 but could hear no difference when I used single-ended connection (1 meter cables).

braminator
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Very Very disappointed in the Marsh's ability to work with the SL3. Being sold has we speak. Time for another amp.

CharlyD
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What are you finding so disappointing? What amps are you trying next?

RGibran
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Word is the Marsh must be used via its balanced inputs to hear its full capabilities. Said to be a completely different animal. Some components are that way. May be worth borrowing a balanced pre just to be sure before you sell off the bargain.

RG

braminator
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The Marsh amped sounded very nice. Sort of tube like. But it could not drive them with any real volume levels that I want. So I sold it. I just picked up a Dk desing integrated amp and all I can say now is holy s**t. My speakers never sounded this good with many different amps. The Dk i can not even turn up past 40-50% with out over powering my 19.8x19.8 room. No joke. This has the sound quality I was looking for with massive power. I would recommend this to anyone with Martins.

CharlyD
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Congratulations on finding an amp that floats your boat. You're not alone in your favorable impressions of this box, have a look at this review. Looks gorgeous, and the price is right!

braminator
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The more I play it, the more I like it. I would like to try several different tubes just for hearing the difference. I have now played all kinds of music and I can not even come close to using all the power of this beast. 40-50% tops and I over power my room.
Bass is real strong and mids and highs are very pleasing.
I have some Siemens cca's in it now. Anybody recommend their opinion on some 6922,6dj8, or tohers like them to work in this killer machine?

braminator
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Well I must confess, I have now hit the limits of this amp as well trying to drive the SL3 to concert level in my 20x20 room. I like the amp a lot. The sound, when changing the tubes to Amperex PQ's was very pleasing to my ears. But I think the Logans are doing me no justice in the type and volume of music I want.
I guess it might to time to sell them and start over. My only issue is this is a second room set up. SO is it worth it? I guess only I will know that.

RGibran
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I believe you have accurately assessed the situation. I don

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Pardon me if I'm overstepping a line but maybe what you really need is a great dealer. Qualified dealers are worth their weight in gold, especially for those just getting into the hobby. If you tell them what you've owned, what you thought of it, what kind of music you like, and what kind of sound you are looking for they can make assembling a system a painless process. That way, you're not learning with your wallet via an orgy of equipment buying and selling until you stumble onto a good combination.

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