Monolith3 Replacement Woofers

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mikebecerr1258

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Okay... If I wire it per your Note from yesterday, then please confirm that wiring from the K231 Mid to the Amp that drives the Woofer, then in fact now makes the Woofer into a Mid-Range frequency reproducing speaker, since the XO modules are set at 300Hz & 80 Hz (Above 300Hz are sent to the Electrostatic Panel & Below 80Hz are sent to the Sub-Woofer).

Then, it is extremely important for me to set the K231 Mode Switch to either a 2-Way or 3-Way (which one should I set it to?). I am under the belief that it should be set to 3-Way, with the K231 High & Mid outs wired out to the 2 Amps which drive the Panel and the Woofer/Mid-Range, and the K231 Sub out not wired to anything (since the Rotel will be wired directly to the SVS Subs 1 & 2). And will the Rotel directly to the SVS Sub 1 & 2 connection yield the proper 80Hz to 20Hz signal required for these subs?

I apologize for seemingly asking this question from perhaps a different direction... but I am truly confused... and I certainly don't want to damage any of my equipment nor miss out on the best possible audio reproduction!

Thanks again...
 

JonFo

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Okay... If I wire it per your Note from yesterday, then please confirm that wiring from the K231 Mid to the Amp that drives the Woofer, then in fact now makes the Woofer into a Mid-Range frequency reproducing speaker, since the XO modules are set at 300Hz & 80 Hz (Above 300Hz are sent to the Electrostatic Panel & Below 80Hz are sent to the Sub-Woofer).
Yes, the woofer of the Monolith is only covering 80 to 300Hz, regardless of the XO settings, as the Rotel will only pass 80Hz to 20KHz out the L/R outputs anyway. The Rotel sub out will send all signals below 80Hz to the two subs.

Then, it is extremely important for me to set the K231 Mode Switch to either a 2-Way or 3-Way (which one should I set it to?). I am under the belief that it should be set to 3-Way, with the K231 High & Mid outs wired out to the 2 Amps which drive the Panel and the Woofer/Mid-Range, and the K231 Sub out not wired to anything (since the Rotel will be wired directly to the SVS Subs 1 & 2). And will the Rotel directly to the SVS Sub 1 & 2 connection yield the proper 80Hz to 20Hz signal required for these subs?
I think it needs to stay in the 3-way, as the unit is loaded with modules for such a config. But maybe it's possible for it to run as a 2-Way just by using the switch and internally no changes, but only the vendor can tell you that.

Here's the question to ask:

" I now have a preamp with a time-aligned subwoofer crossover output for two subs, and don't really need the K231 to operate as a 3-way crossover. If I switch the 2-way vs 3-way switch to 2-way, will it crossover the high at 300Hz and the low-pass is now a pure 300Hz low-pass (vs a bandpass in a 3-way)?
And if so, what inputs/outputs should I use for wiring if I change the switch to 2-way? "

You also might want to include a link to this thread so he has some more background.

But for now, to get going, wire it per the earlier instructions and leave it in 3-way mode.
 

mikebecerr1258

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Since when this whole thing started, the preamps you contemplated did not have sub outs or the level of sophistication the Rotel has, the thought was to place all crossover duties in the K231, so that's how you ordered it.
But now that the Rotel is here, the configuration on the K231 is a bit overkill, as all you need is a two way.
Since the modules and options are likely loaded up for 3-way operation, my latest instructions are to essentially use 2/3rds of the units I/O, basically, using it as a 2-way.

Functionally, that's fine, and you should wire it per my note yesterday with no changes to the K231 settings other than setting the levels.


Understood, that sub model is RCA inputs only, make sure you use the one marked LFE and set the setting to use LFE mode.
JonFo... was wondering if it makes any sense to connect the SVS Subs to the Rotel Preamp via XLR cables instead of RCA (each "run" is approx. 20-25'). The curveball to this is that although the Rotel has an XLR output, the SVS Subs only accept RCA input connections... thus I would have to place an XLR-to-RCA Adapter on the far ends of the XLR cables in order to hook them up to the Subs. Upon doing so, will this adapter negate the advantages of using an all XLR cable rather than an all RCA? In other words, am I throwing away my hard-earned money???
 

JonFo

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I would have to place an XLR-to-RCA Adapter on the far ends of the XLR cables in order to hook them up to the Subs. Upon doing so, will this adapter negate the advantages of using an all XLR cable rather than an all RCA? In other words, am I throwing away my hard-earned money???
It would be best to use RCA-to-RCA in this scenario, as you gain nothing compared to XLR with a conversion back to unbalanced. So save your money, and just get a set from this page: Subwoofer Cables from Blue Jeans Cable
 

Leporello

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JonFo... was wondering if it makes any sense to connect the SVS Subs to the Rotel Preamp via XLR cables instead of RCA (each "run" is approx. 20-25'). The curveball to this is that although the Rotel has an XLR output, the SVS Subs only accept RCA input connections... thus I would have to place an XLR-to-RCA Adapter on the far ends of the XLR cables in order to hook them up to the Subs. Upon doing so, will this adapter negate the advantages of using an all XLR cable rather than an all RCA? In other words, am I throwing away my hard-earned money???
Common mode rejection (CMR) is done at the receiving end, where the two out of phase signals plus noise are combined. So no, there is no advantage to using a balanced output at the other end.
 

mikebecerr1258

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The P6 is a nice preamp to easily create a 2.1 analog setup. But spendy.
The XO is strictly a .1 - related thing. The user can choose the crossover point for High-Pass separately from low-pass and whether to enable it or not. So easy to integrate a subwoofer into a 2ch system.
If you plan to stay with a passive XO for the Monoliths, this is a nice preamp.

But if wanting to go active XO for the Monoliths, this P6 is insufficient, as it does not have the two additional outputs and XO circuits required to perform the 2x4 active XO.



Correct, if you really want to use the P6 in an active XO scenario, you still need an external active crossover between the L/R outputs of the pre-amp (with high-pass out filtering as you have a sub) fed to the L/R inputs of the active XO and then the high and low outs per channel feed the respective amp channels.
The sub(s) would be fed by the P6 sub ouput.

So a P6 + a Sublime Acoustics 2-way XO (high pass @300Hz , low-pass at 300Hz) would be the minimal gear necessary for a 2.1 with active two-way XO. And yes, two stereo amps are required.
JonFo - need your advice once again. In an earlier thread I believe you discussed your research on the best active XO frequencies was at a minimum 330 Hz for the ESL to switch over to the 12" woofer. In the thread or snapshot above, you mention the high pass/low pass @ 300 Hz. I need your honest opinion as to which measurement is best, as I had ordered my Sublime Acoustic XO with a 300 Hz module. Now wondering if I should also order a 330 Hz ( or higher ) module for a better sounding end result? Thanks...
 
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