Sub Bi-Amp Crossover Frequency for Ascent I

[randallp]

Hi ML Owners,

What's the preferred crossover frequency for the Martin Logan Ascent i 10" subs? From what I read in the owner's manual, the panels are at a 280Hz crossover point. The reason for the question is I don't want to my sub crossover point so low that I miss critical low frequency elements between the sub and the panel crossover points (i.e., if the sub is set at 150Hz and the panel is set at 280Hz, my assumption is I have lost the frequencies between 150Hz and 280Hz creating a hole in my audio reproduction).

Thoughts? Thanks, Randall

 

[ralflar]

You cannot actively bi-amp Ascents. Only passive bi-amping is supported. Therefore both amps must work over the same frequency range - no active crossover between the two!

 

[Spike]

You cannot actively bi-amp Ascents. Only passive bi-amping is supported. Therefore both amps must work over the same frequency range - no active crossover between the two!

Sure you can actively bi-amp the Ascents by putting the active crossover in front of the amplifiers. The caveat is that the internal crossover cannot be easily bypassed at all. Therefore, you're going to reduce the benefits of bi-amping by having active crossover working in conjunction with the passive ones of the Ascents. Sure, the amplifier may work more efficiently, but you are adding more components into the chain, contaminating the original signal. In this case, adding an active crossover is not an optimal solution

Spike

 

[randallp]

Let me give you more informaiton to make sure I understand

No matter if I run the Ascent i's full range or bi-amp, the internal crossover of the Ascent i's will cross the 10" drivers at 280Hz and down? Is this correct?

Thank you!

Randall

 

[Spike]

No matter if I run the Ascent i's full range or bi-amp, the internal crossover of the Ascent i's will cross the 10" drivers at 280Hz and down? Is this correct?

That's correct. The internal passive crossover is always in the chain and you have to manually remove it if you:

1. Have access to the schematic and possess basic electronic knowledge to understand the schematic!
2. Are handy with the soldering iron.

Spike

 

[ralflar]

Combining active and passive crossovers like that is simply a very bad idea. The fact that the connections can be made does not mean that it makes sense to do so. You cannot actively bi-amp Ascents in a practical way unless the passive crossovers are removed.

Sure you can actively bi-amp the Ascents by putting the active crossover in front of the amplifiers. The caveat is that the internal crossover cannot be easily bypassed at all. Therefore, you're going to reduce the benefits of bi-amping by having active crossover working in conjunction with the passive ones of the Ascents. Sure, the amplifier may work more efficiently, but you are adding more components into the chain, contaminating the original signal. In this case, adding an active crossover is not an optimal solution

Spike

 

[ted99]

Difference between Ascent and Ascent i's?

I don't have a schematic of my Ascents, so let me see if I understand this correctly. My Ascents have separate connectors on the back for the upper panels and the lower cone speaker, and a jumper to bridge the two. If I bi-amp the two, the crossover is still in the circuit for both? I thought by biamping, I was driving the panel with one amplifier and the cone with a different amp. Or, are you saying that the crossover(s) are still in the circuit for each section of the speaker and the panels have a low frequency rolloff and the cones still have a high frequency rolloff? I'm not bothered by this, because it still means that I'm driving each section with a separate amplifier.

Can anyone send me a schematic? [email protected]. Thanks.