Biamp

[Digitalhitech08]

I tried to Biamp but the Marrantz jump into the protective mode.
I have the
Marrantz AV 7705
Marrantz MM7055
Marrantz MM7025
Martin Logan EM-ESL X

I just want to know if this can be Biamp which option vertical or horizontal, and the settings on the preamp. Thank you

 

[ryanosaur]

There is really no good reason to bi-amp. You are much better off getting an amp capable of driving your speakers properly with good clean power at their impedance.

Did you unit recover when hooked up conventionally, single lead to each low or high binding post with jumpers attached? When you tried this, did you remove the jumpers from your Speakers?

 

[Leemix]

Y cable from the processor to the 2 amps, no settings in the processor.
Horizontal is generally best if not the exact same amps, often preferred anyway.
You might not notice any difference and make sure the amps play at the same level if they have a gain knob so you dont accidentally increase the lower or upper parts in relation to the other.

Edit: as ryanosaur wrote make sure you remove the jumpers if you havent, it can really damage the equipment if not removed.

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[Digitalhitech08]

There is really no good reason to bi-amp. You are much better off getting an amp capable of driving your speakers properly with good clean power at their impedance.

Did you unit recover when hooked up conventionally, single lead to each low or high binding post with jumpers attached? When you tried this, did you remove the jumpers from your Speakers?

Yes I had removed the jumpers, at first I only used the 7055 it went into protected mode I call marrantz they said that the amp don't have enough power so I just bought and 7025 which have the same power of the 7055 5 channel. I used the 7055 for the low & the 7025 for the high I also use the y splitter from the preamp.

 

[ryanosaur]

And did it work, or no?

Still, dunno what you are trying to accomplish.

No harm doing it if you are set up properly, but there really is no evidence I've ever seen of any benefit to doing this. The problem is, if you aren't set up properly...

 

[Leemix]

The 7025 doesnt look more powerful than the 7055, it looks like the same but only 2ch so if you need more power its better to get another more powerful amp rather than bi-amping which doesnt really give more power but only separates the upper and lower ranges.


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[Verdinut]

I tried to Biamp but the Marrantz jump into the protective mode.
I have the
Marrantz AV 7705
Marrantz MM7055
Marrantz MM7025
Martin Logan EM-ESL X

I just want to know if this can be Biamp which option vertical or horizontal, and the settings on the preamp. Thank you

In order to actively bi-amp your Martin Logan speakers, you would need to get a pair of electronic crossovers to split frequencies and drive four power amplifiers. If your power amps struggle to drive the ML speakers, IMO more powerful amplifiers would be more appropriate. On the other hand, if you are satisfied with your Marantz amps, you will not get any audible improvement with more powerful amps or with bi-amplification.

 

[TLS Guy]

Yes I had removed the jumpers, at first I only used the 7055 it went into protected mode I call marrantz they said that the amp don't have enough power so I just bought and 7025 which have the same power of the 7055 5 channel. I used the 7055 for the low & the 7025 for the high I also use the y splitter from the preamp.

I suspect your issue is not so much lack of power, but a stability problem. Any Electrostatic speaker presents a very complex load to an amp. It is called a reactive load, and is very inclined to induce ultrasonic oscillation in power amps. This situation is an absolute killer for power amps. It is hard to know how dividing the the low and high pass crossovers would impact the load. However it is clear that your amp units are not up to job and you will destroy them if you persist.

In general electrostatic speakers should be driven by amps unconditionally stable under all loads. The only amps that I am certain meet that criterion are Quad amps from the Acoustical manufacturing company Huntingdon UK. Peter Walker the founder invented the electrostatic speakers, and amp stability was one of his biggest challenges. All this is detailed in his biography, The Closest Approach.

 

[lovinthehd]

You've double/triple checked all your wiring? At what sort of spl levels does it go into protection?

Those Marantz amps are not the most robust but no reason they should go into protection immediately. Marantz' reaction sounds suspect in any case, it doesn't have enough power for what spl levels did you tell them? I wouldn't bother with the passive bi-amping in any case. There are many other amps outside of the Quads TLS mentioned.

 

[Verdinut]

Can you return the MM7025 for a refund?

You would need a very stable power amplifier such as the pro audio QSC DCA 1622, a 2 channel unit with a power rating of over 375 watts/ch at 6 ohms. If your main listening position is 10 feet or more from it, you shouldn't hear the cooling fan.

I am using this series of Cinema power amps in my HT system. These are used in Cineplex theaters all across North America. They are solidly built in the US and you can't blow them. They are not sold in pro audio shops. You have to verify on QSC's site to find a theater equipment distributor. I recommend them without any hesitation.

DCA 1622

Crystal-clear, breathtaking, seat-shaking cinema sound is here with the DCA 1622 Digital Cinema Amplifier by QSC

www.qsc.com

 

[Mark E. Long]

Can you return the MM7025 for a refund?

You would need a very stable power amplifier such as the pro audio QSC DCA 1622, a 2 channel unit with a power rating of over 375 watts/ch at 6 ohms. If your main listening position is 10 feet or more from it, you shouldn't hear the cooling fan.

I am using this series of Cinema power amps in my HT system. These are used in Cineplex theaters all across North America. They are solidly built in the US and you can't blow them. They are not sold in pro audio shops. You have to verify on QSC's site to find a theater equipment distributor. I recommend them without any hesitation.

DCA 1622

Crystal-clear, breathtaking, seat-shaking cinema sound is here with the DCA 1622 Digital Cinema Amplifier by QSC

www.qsc.com

Those are very nice really good specs . Do they run hot at all ?

 

[TLS Guy]

I suspect your issue is not so much lack of power, but a stability problem. Any Electrostatic speaker presents a very complex load to an amp. It is called a reactive load, and is very inclined to induce ultrasonic oscillation in power amps. This situation is an absolute killer for power amps. It is hard to know how dividing the the low and high pass crossovers would impact the load. However it is clear that your amp units are not up to job and you will destroy them if you persist.

In general electrostatic speakers should be driven by amps unconditionally stable under all loads. The only amps that I am certain meet that criterion are Quad amps from the Acoustical manufacturing company Huntingdon UK. Peter Walker the founder invented the electrostatic speakers, and amp stability was one of his biggest challenges. All this is detailed in his biography, The Closest Approach.

Quad amps are specifically designed to work optimally with reactive loads of electrostatic speakers. That is because Quad has been the world leader in electrostatic speakers since 1957. So yes, there amps you can rely on to drive reactive loads optimally. Moving coil speakers never present a reactive load with positive phase angles, especially in the high frequency region. You have to remember I was in regular contact with Peter Walker and made a number of trips to Huntingdon.

Amps blowing up driving electrostatic speakers is a well known and documented problem.

 

[lovinthehd]

So it's more a defective speaker technology that Quad needs its "special" amp technology to overcome?

 

[Verdinut]

Those are very nice really good specs . Do they run hot at all ?

They never get hot. As a matter of fact, with my DCA 1222s, I could easily drive four 8 ohm speakers in parallel. This is what QSC does in Cineplex theaters.

My 7 Channel System

SYSTEM: MARANTZ SR5010, 3 QSC DCA 1222 AMPS. DRIVING THE FRONT CHANNELS IN ACTIVE BI-AMP CONFIG. QSC DCA 1824 (4 CH. AMP.) FOR SURROUND CHANNELS OPPO BDP-95, REVOX B77, TEAC AN-80 (NR), AUDIO-TECHNICA AT-LP1240, SHURE M97XE, HITACHI HCA-8300, PANASONIC TH-50PZ80U, FURMAN PS-8R, APC H15 FRONT...

forums.audioholics.com

https://www.brucesentertainment.com/QSC_Cinema_Catalog.pdf

 

[Mark E. Long]

They never get hot. As a matter of fact, with my DCA 1222s, I could easily drive four 8 ohm speakers in parallel. This is what QSC does in Cineplex theaters.

My 7 Channel System

SYSTEM: MARANTZ SR5010, 3 QSC DCA 1222 AMPS. DRIVING THE FRONT CHANNELS IN ACTIVE BI-AMP CONFIG. QSC DCA 1824 (4 CH. AMP.) FOR SURROUND CHANNELS OPPO BDP-95, REVOX B77, TEAC AN-80 (NR), AUDIO-TECHNICA AT-LP1240, SHURE M97XE, HITACHI HCA-8300, PANASONIC TH-50PZ80U, FURMAN PS-8R, APC H15 FRONT...

forums.audioholics.com

https://www.brucesentertainment.com/QSC_Cinema_Catalog.pdf

Thanks for the link very near stuff . It would be neat to be able to have behind the screen setup like those in the link .

 

[Verdinut]

Those are very nice really good specs . Do they run hot at all ?

I just wanted to add that those DCA series amps use a SMTP switching power supply which allows them to run cooler. An interesting fact is that they were released in 1998 and never were modified since. That's the reason why they've kept their model number. Why change something that was well designed and performs well? Another interesting feature is that they all weigh only 21 lbs.

 

[TLS Guy]

So it's more a defective speaker technology that Quad needs its "special" amp technology to overcome?

Its not defective. It is that electrostatic speakers have totally different technology behind them, and the physics is poles apart. Electromagnetic speakers use wire coils in a magnetic gap, and the load is inductive. In Electrostatic speakers you are driving a large polarized capacitor as the load is reactive. The relationship of voltage and current are exact polar opposites. Quad amps drive both types of load equally well, and most do not. The fact remains that Peter Walker was a genius, and we all owe him an outstanding debt.
I was there when his first electrostatic speaker was demonstrated, as it sent shock waves throughout the audio industry. The Quad ESL 57 is widely recognized as the world's first truly tonally accurate speaker. It showed what was was possible for the reproduction of music and was a landmark in audio progress.

The technology was in no way defective, but different. Literally 180 degrees different!