Need help. Pairing Martin Logan Sequel II with 4 Watt tube power amp

[areniers]

Hi,

I'm new here. So here comes my first question. I have a pair of Martin Logan Sequel II electrostatic loudspeakers. In a few weeks I'll also have two tube monoblocks with 4 Watts output power. The tubes used are 1x300B, 1x6SL7 and 1x5U4 (rectifier).

Would it be possible to pair these directly (without preamp) with the Martin Logans, which have a sensitivity of 89dB?

Would adding a preamp (solid state or tube) actually alter the situation in any way, given the monoblocks still only posses 4 watts to hand out? If a preamp is desirable what should I look out for?

So in all, what would be the best solution to pair up these monoblocks with the Martin Logans?

Looking forward to reading your replies!

Alvin from Belgium

[Feanor]

Hi,

I'm new here. So here comes my first question. I have a pair of Martin Logan Sequel II electrostatic loudspeakers. In a few weeks I'll also have two tube monoblocks with 4 Watts output power. The tubes used are 1x300B, 1x6SL7 and 1x5U4 (rectifier).

Would it be possible to pair these directly (without preamp) with the Martin Logans, which have a sensitivity of 89dB?

Would adding a preamp (solid state or tube) actually alter the situation in any way, given the monoblocks still only posses 4 watts to hand out? If a preamp is desirable what should I look out for?

So in all, what would be the best solution to pair up these monoblocks with the Martin Logans?

Looking forward to reading your replies!

Alvin from Belgium
I'll comment and I hope others will too. First, let me say that the Martin Logan Sequel II look like interesting speakers though they might pose issues for some amps.

See the Stereophile review HERE (http://www.stereophile.com/floorloudspeakers/889mlseq/index.html).

With out a preamp, how will you control the volume for the ML's? This is a prominent reason for preamp. In any case a preamp won't "alter the situation" vis-a-vis the low-power monoblocks and the ML's. The fact is that 4 wpc amps very unlikely to be workable with the ML's or any speaker of 89dB sensitivity.

Beyond simply not having enough power, you amps might struggle with the complex load posed by the ML electrostatics (or other electrostatics). The reactive load of the ML's might damage the amps and/or cause the amps to damage the speakers, but there are people here at AR who will be better informed -- hopefully they will comment further.

[areniers]

Thanks for the reply, Feanor.

Actually the monoblocks do have volume knobs (which makes me wonder if they're not in fact integrated amps; or am I jumping to conclusions here?). Does a power amp with a volume knob actually exist or is it an oxymoron?

I also have a pair of Acoustic Research Status S40 speakers, which have a sensitivity of 91dB. Maybe they would be a better match for the monoblocks; or should I start looking for some really sensitive speakers?

Thanks,
Alvin

[LeRoy]

Hi Alvin,

ML Sequel 2's. Man, one of the best audio systems I 've ever heard (back in the 90's) was ML S 2's with Addcom amp and Addcom Pre. I have always loved that particular paring. So, you're thinking about a 4 watt amp to drive them and it's very unlikely that 4 watts is going to do it.... Do you have the brand name and model# of the amp (or integrated) that you are writing about?

[areniers]

The ML's are currently driven by a self built (not by me) hybrid Class A power amp delivering about 45 wpc into 4 Ohm (25 wpc into 1 Ohm) (the amp is an AT-25 from Audio&Techniek). It has two Mosfets pc (2SK135/2SJ50) and two e88cc tubes.

The ML's sound really great through this power amp. There's just a passive pre-amp in between to control the volume. The ML user manual states a 80W amp as recommended, but really the AT-25 is doing just fine with it.

The mono blocks are also self built by the seller, so I'm going to ask him for some more specifics about their layout. I do know they have volume knobs.

Alvin

[Mr Peabody]

As others stated the 4 watt amps will not drive the Martin Logan. The Class A amp is a good match because Class A usually sounds more powerful than it's rating due to theoretically no distortion and I would be certain it's also high current. The Martin Logan are very nice with a strong enough tube amp to push them. 89 dB may get some sound from an amp but ML's impedance tends to swing low, they usually do better with ultra linear higher power tube amps or solid state with good current output.

Sometimes power amps do have gain controls but seems unnecessary for only 4 watts. I would recommend looking for a very high efficient speaker to use with the monoblocks, like Audio Note, Zu Audio or even certain Klipsh.