New Member, not so new Sequel II's

[jemmanuelle]

Purchased new back around '87, new panels 10-15 years ago. B&K pre and power. Love the midrange, but could use
suggestions for an amp that could show this speaker who's boss.

 

[Brandon Hartwick]

Martin Logan ESLs love current, look for something with a good size power supply and can run 4 ohm nominal without issues.

The best thing you can do with the older passive ESLs is bypass the woofer crossover entirely and bi-amp it on its own using an amplifier with its own electronic crossover. This provides far more improvement than just buying bigger/more expensive amps. The new Crown XLS amplifiers do a fantastic job at this.

 

[Brad225]

Welcome jem. What took you so long to find us?
Have you looked at the sticky thread on amps. Also try going through members systems and see what others are using.
It is a dangerous question as we all love to help members spend money.

 

[jemmanuelle]

Martin Logan ESLs love current, look for something with a good size power supply and can run 4 ohm nominal without issues.

The best thing you can do with the older passive ESLs is bypass the woofer crossover entirely and bi-amp it on its own using an amplifier with its own electronic crossover. This provides far more improvement than just buying bigger/more expensive amps. The new Crown XLS amplifiers do a fantastic job at this.

Thanks for the advice, Brandon. Was giving this some thought. Liked what I saw at this sight. Xkitz Electronics
So, to bypass the woofer, do you simply disconnect the woofer at the ML crossover, remove the jumper at the speaker terminals,
and then feed the woofer directly from the bass amp?

 

[Reverb]

Welcome to ML, and enjoy the forum. Can you post some photos of your current setup?

 

[Brandon Hartwick]

Thanks for the advice, Brandon. Was giving this some thought. Liked what I saw at this sight. Xkitz Electronics
So, to bypass the woofer, do you simply disconnect the woofer at the ML crossover, remove the jumper at the speaker terminals,
and then feed the woofer directly from the bass amp?

I'm sure the stuff on that site will work if you know how to hook everything up, there's many options out there for electronic crossovers. I like the new class D pro amps for there simplicity and clean sound.

You can simply de-solder the connections on the woofer binding posts and run the wire direct to the woofer. Alternatively you can just install another pair of binding posts and run cable to the woofer, that's what I did as I didn't feel like messing with the crossover connections. A week or so ago I wrote a decent thread on it in the mods section.

 

[Heyfey]

If you're going to bypass the passive X-O and bi-amp you might consider EQing the bass signal as well. I'm using a miniDSP product to do that on my pair of Theos. Home | miniDSP

 

[jemmanuelle]

I'm sure the stuff on that site will work if you know how to hook everything up, there's many options out there for electronic crossovers. I like the new class D pro amps for there simplicity and clean sound.

You can simply de-solder the connections on the woofer binding posts and run the wire direct to the woofer. Alternatively you can just install another pair of binding posts and run cable to the woofer, that's what I did as I didn't feel like messing with the crossover connections. A week or so ago I wrote a decent thread on it in the mods section.

I have attached the schematic for the Sequel II crossover. My goal is to completely bypass both the HF and LF crossover and
use an active crossover after the preamp which will feed HF and LF amps. Then take the speaker outs from the LF amp and
connect directly to woofer terminals and the speaker outs from the HF amp and connect to the primary terminals of the transformer upstream of the electrostatic panel. Is this the correct approach?

 

[Mwilder]

Purchased new back around '87, new panels 10-15 years ago. B&K pre and power. Love the midrange, but could use
suggestions for an amp that could show this speaker who's boss.

I have original sequels. I purchased in 2000. The panels are a little dull now. I was driving mine wth B&K PT3 & ST2140. Nice sounding but not near enough power. A friend has Summits with a pair of mono blocks. Huge difference.

 

[jemmanuelle]

I have attached the schematic for the Sequel II crossover. My goal is to completely bypass both the HF and LF crossover and
use an active crossover after the preamp which will feed HF and LF amps. Then take the speaker outs from the LF amp and
connect directly to woofer terminals and the speaker outs from the HF amp and connect to the primary terminals of the transformer upstream of the electrostatic panel. Is this the correct approach?

Anyone with the expertise to comment on this approach?

 

[Brandon Hartwick]

Anyone with the expertise to comment on this approach?

If you're trying to drive everything direct and use electronic crossovers and DSP for everything than this is the correct approach. I have not tried active crossovers on the ESL panel but it would definitely be an interesting experiment to try.

If you do this please post up your results, I'm curious.

 

[JonFo]

I have attached the schematic for the Sequel II crossover. My goal is to completely bypass both the HF and LF crossover and
use an active crossover after the preamp which will feed HF and LF amps. Then take the speaker outs from the LF amp and
connect directly to woofer terminals and the speaker outs from the HF amp and connect to the primary terminals of the transformer upstream of the electrostatic panel. Is this the correct approach?

Yes, that is generally the idea. And you can look at my SL3XC project thread for all the necessary details, as the SL3 and Sequels are fairly close in design (they actually use the same panel), since the '3' in SL3 is basically a Sequel 3. Post#15 in that thread has the modified schematic and descriptions.

Do pay attention to the required impedance on the feed to the HF transformer, as many amps will oscillate if direct-driving the ESL. And I can tell you that Sunfire and Sanders Sound Systems amps will happily drive the bare panel all day long, so those should be on your short list for panel amps.

 

[Reverb]

I have attached the schematic for the Sequel II crossover. My goal is to completely bypass both the HF and LF crossover and
use an active crossover after the preamp which will feed HF and LF amps. Then take the speaker outs from the LF amp and
connect directly to woofer terminals and the speaker outs from the HF amp and connect to the primary terminals of the transformer upstream of the electrostatic panel. Is this the correct approach?

Hello, how did it go with that approach?