Active x-over ReQuest

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Shaftish

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I´m thinking about connect a MiniDSP to my woofers.
Anyone knows if that is a good idea?

Running Adcom GFA555ii to the 12" and McIntosh Mc275 to the panels.
 

JonFo

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Going active is always a plus; many of us here have done that.

There have been a few threads around the active XO on a request, a quick search should surface those.

What topology are you proposing, fully active, replacing the passives on both the woofer and the panel, or just a bypass of the passive on the woofer?
 

Shaftish

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As a first step i was thinking of just bypass the woofer.

Nice to hear that it's been done with good results
 

DanR

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Yep I just about have my Odysseys dialed in now after bypassing the passive crossover to the woofers. It was a simple straight forward process and the results were excellent and not minor, the speakers sound so much better now the bass is much quicker and cleaner. I bought my Odysseys 2 months ago they are 21 years old and I have a new pair of panels on order, one of my panels is in the check out line😂 but still sounds great up to moderate volumes. I did replace all 4 of the woofers when I bypassed the passive crossovers as well. If you simply disconnect the passive crossover by taking the wires off of the low frequency binding posts and taping the wire ends and leaving them in the enclosure you can go back to the passive crossover any time you want. Put your own wire in directly from the binding post to the woofer and you are good to go. You’ll have to play around with the settings on your dsp to get it just right.
 

Brandon Hartwick

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This mod is 100% worth it, there's basically no downside other than the added hassle of additional amps and cables. The passive bass crossovers in most Martin Logan speakers are less than great.

My speakers now run totally active with no passive networks at all, but the woofer is a good starting point and yields the most noticeable results.

I made a thread detailing how to bypass the stock passive crossover.
 

Heyfey

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Yep I just about have my Odysseys dialed in now after bypassing the passive crossover to the woofers. It was a simple straight forward process and the results were excellent and not minor, the speakers sound so much better now the bass is much quicker and cleaner. I bought my Odysseys 2 months ago they are 21 years old and I have a new pair of panels on order, one of my panels is in the check out line😂 but still sounds great up to moderate volumes. I did replace all 4 of the woofers when I bypassed the passive crossovers as well. If you simply disconnect the passive crossover by taking the wires off of the low frequency binding posts and taping the wire ends and leaving them in the enclosure you can go back to the passive crossover any time you want. Put your own wire in directly from the binding post to the woofer and you are good to go. You’ll have to play around with the settings on your dsp to get it just right.
Dan, I have Odysseys with new panels and I upgraded all the caps to Mundorfs about 8 years ago but am still in the upgrade game. I'm curious about: what woofers you used to replace the stock ones and are you running one amp for both woofers or separate amps for each woofer? Thanks.
 

DanR

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Hi there, first let me know how it went with the new panels on your Odysseys did you install tjem yourself and if so was it an easy straight forward remove and install? And how did the new panels sound?
On mine I use two amps for the woofers one for the 8” and one for the 10”. They are both relatively inexpensive pro amps but are A/B amps not digital which is awesome. I use a Behringer DCX-2496 for my dsp I use it to set my crossover parameters for the woofers on the Odysseys and also for 3 subwoofers I run in my system a 18” sealed diy, a 15” sealed diy, and a 12” powered SVS sub. Here is the list of equipment I modded the Oddyseys with
Amps:
Crown XLi 800 from Sweetwater $329
Behringer KM-750 from Sweetwater $219
Woofers:
8” ScanSpeak 22W4534G00 Discovery 8” woofer 4ohm from Madisound $196.01 pr
10” Dayton Audio DS270-8 10” Designer Series woofer 8ohm from Parts Express $198.80 pr
I use the behringer amp on the 8ohm 10” which puts out 200 watts at that load
And the crown on the 8” which puts out 200 watts at that load
My amp for the panels is a Krell KSA-100 MK-II which puts out 200 watts class A at the panels load so everything is matched power wise.
 

DanR

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So yes when I have the system up and running it uses 5 amps 6 if you count the plate amp in the SVS sub. My 18” sub gets 2400watts from a Behringer EP4000 and the 15” sub gets 950watts from another behringer EP4000. Those amps are in another room and another circuit.
 

Tosh

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Around 2014 my friend had a MiniDSP on his (my former) ML SL3, and because it first did an A to D conversion, it sounded pretty bad in the top end. But for the bass it was good. Can you get around needing to A-D the top end with today's MiniDSP? Sources are sometimes analog.
 

rawatch

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Around 2014 my friend had a MiniDSP on his (my former) ML SL3, and because it first did an A to D conversion, it sounded pretty bad in the top end. But for the bass it was good. Can you get around needing to A-D the top end with today's MiniDSP? Sources are sometimes analog.
I only use dsp for bass, i use a passive analog high pass filter for the panels sounds great, dsp for the panels to much smearing
 

Heyfey

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Dan, I have Odysseys with new panels and I upgraded all the caps to Mundorfs about 8 years ago but am still in the upgrade game. I'm curious about: what woofers you used to replace the stock ones and are you running one amp for both woofers or separate amps for each woofer? Thanks.
Sorry for the delayed reply, I was out of the country and wasn't keeping up with "the usual stuff." I replaced my Odyssey panels about a year ago and the only snag was that when I screwed one side into the wood side rail there was a 15mm gap on the other side between the new stat panel and the wood side rail. I removed the screws and, while gently pushing the two wood side rails together, fastened the top screws on both sides and then worked my way down. Did it myself though a helper could be useful. Marginal sound improvement as the original panels weren't shot. I considered it a preemptive strike. I'd had them for 12 years and bought them new from a dealer who had them unboxed in their warehouse area for probably 5 years.
 

Robert D

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Sorry for the delayed reply, I was out of the country and wasn't keeping up with "the usual stuff." I replaced my Odyssey panels about a year ago and the only snag was that when I screwed one side into the wood side rail there was a 15mm gap on the other side between the new stat panel and the wood side rail. I removed the screws and, while gently pushing the two wood side rails together, fastened the top screws on both sides and then worked my way down. Did it myself though a helper could be useful. Marginal sound improvement as the original panels weren't shot. I considered it a preemptive strike. I'd had them for 12 years and bought them new from a dealer who had them unboxed in their warehouse area for probably 5 years.
I had some difficulty putting on my Prodigy panels too, but like you I finally worked it out.
 
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