Monolith3 Replacement Woofers

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JonFo

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Oops, missed these, and I replied via PM, so sharing the content here for posterity.

Hi Mike,

The factory passives are not easy to work on, as they made them pretty complex, so achieving an improvement gets both hard and expensive. Most with the skills to even attempt that just ditch them and go active.
I can not recall anyone performing a significant mod on those in the past 15 years (that I'm aware of).

I looked at the specs for that Goldwood, and compared them to the alternatives I might have suggested from Visaton or Dayton Audio, and frankly not much difference, especially considering cost and effort.
If anything, the Goldwood seems better suited to the large sealed space of our Monoliths and reaches lower. Its mid-bass performance is actually not that bad, it is not really a subwoofer, just a 'heavy duty woofer'.

The only woofer model that seems to offer a benefit in specs is the rather expensive ArumCantus AC300and I still feel that if you use a sub, you'll still not hear many benefits from that either. If no sub, then sure. But these ESL speakers positioning generally means one needs a sub regardless.
Also, one would want to double-check the physical fit as well, as these Euro woofers are often a few mm different than the usual US/Asian 12" drivers.

I hope that helps,

Jonathan
 

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Well, that right there is why the sound is not the best, as a tube amp and those woofers are not a good pairing, much less through a passive XO. And 70w is not enough for those panels, and worse due to losses in the XO.

But since you intend to switch to a more powerful amp, you should see better results with the EP driving the passive. But it's still a passive XO, not even the mighty Sanders ESL amp will make that sing.

Thanks for sharing further details about the gear, as that is key to understanding how various options will fit.

Both of your current front ends are integrated models, with pre-amp and amp in a single box, and neither seems to have a pre-out / amp-in loop, which is required to insert an active crossover. So the effort to go active is over unless you are willing to consider fully separate pre-amp / amp options.


Yes, the tech in this thing is pretty cool, but it's been around for two decades. It does depend heavily on the setup software to load and set configurations, so one needs to be comfortable using apps on the PC. And due to its nature as an auditorium-scale management system, it has concepts such as 'Venue' and finally gets down to devices and then presets for the devices. So a bit of unnecessary complexity to manage a single box, but it doesn't really get in the way too much. Then again, I've been in the computer software development space for 45+ years, so what I see as straightforward, may not be to others.
So if comfortable enough driving an app like that to load the pre-made configurations I can send you, the hard stuff will be done for you. The only configuration tweaks we might make are adjustments to input/output gains to match your gear, and the delay settings on the subwoofer output, again, to fit your physical setup.

But, I'll stop there and double-check that the whole active XO path is one you are willing to pursue, as it requires several things to achieve a successful outcome:
  1. Front-end is a pure pre-amp with line-level, volume-controlled outs (balanced preferably)
  2. Two amps, one for panels and one for woofers, matched to their respective roles (balanced ins)
  3. An electronic crossover, DSP-based preferably but could be a fixed analog active XO
  4. Crossover design that suits the Monolith (I can supply that for the DBX)
  5. Measurement system to validate settings and setup, REW software, and a UMIK1 microphone
Right now you have none of those (well, #4), so maybe a rethink of the overall project, as this is both complex and costly. But if willing to go all-in, the results can be impressive.

However, as I usually counsel here, your number one bang-for-the-buck improvement is going to be acoustical treatments of the room housing the ESL setup. And those large Monolith ESL panels need a LOT of room treatments to tame them. A full ton+ (literally) of room treatments in my dedicated room.

So maybe look at deploying the EP amp (since you have it) and look at improving the acoustics. A few hundred bucks there goes a long way.
Hi
Its been some time since we last spoke.
Health issues completely side lined my Monolith 3.
Mine is the one with the 3 not iii.
I have gathered equipment.
I have the Sunfire 600 and Crown to handle the amplification.
Still need a preamp (recommendations)?
Is it the DBX Driverack PA2 that you use? If not,is the unit you use available?
Still need to purchase woofers( Your recommendation now is?)
I have hesitated big time because of the learning curve of DBX unit. Your supplying the config file would make me jump headlong back into the project again.
Look forward to hearing back from you.
 

JonFo

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I can not recall anyone performing a significant mod on those in the past 15 years (that I'm aware of)
OK, I jogged my memory and sure enough, member @modavid did mod his IIIp crossovers while using the Goldwood woofer and reports better results than the Peerless unit he had in there previously, quite possibly because the Goldwood is a better match for the passive crossover. See this thread: Monolith iiixb
 

JonFo

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Is it the DBX Driverack PA2 that you use? If not,is the unit you use available?
My current DBX recommended device is the current DriveRack Venu360.
I have hesitated big time because of the learning curve of DBX unit.
Then you might be interested in the Dayton DSP unit that Brandon references above. Or if you want complete simplicity, this $500 active three-way crossover looks like quite the good value: K231 Stereo 3-Way Active Crossover

Just spec the values I referenced above for the Marchand unit.

Still need to purchase woofers( Your recommendation now is?)
Money no object, that Aurum Cantus AC300 I mentioned above. Otherwise the
Still need a preamp (recommendations)?

or the Goldwood reference in that thread I just linked (and the OP has in his units).

Still need a preamp (recommendations)?
Yes, find a model that already handles 2.1 and possibly includes room correction and save yourself some complications. But those can't get spendy. What's the budget range?
Often, using a great quality older model AVR as a pure preamp can be the answer here, as the video and surround processing sections become obsolete, yet the phono input, all analog processing, and control are still great quality, yet they sell for huge discounts. And because they have HDMI inputs, it's easy to hook up a streaming box such as the AppleTV (and edition) and play back lossless content from Apple Music.
You can even use a $30 HDMI splitter to send 4K video to the TV, and send a 1080p signal with the audio to the AVR. I use one in my HT rig to get Atmos audio, even though my video chain is 1080p for now.
An older Anthem AVR with ARC would make a good choice.

If you use a 2.1 capable pre, then the crossover for the Monoliths only needs to be a 2-way.
 

Brandon Hartwick

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The Dayton unit is very user friendly, the software isn't intimidating at all really. I had my unit setup in about 10 minutes, you can even make multiple crossover programs with different parameters and load them up as you please on the fly.

If you're worried about cost and complexity of the larger DSP units if highly recommend trying one of these, you really can't go wrong for under $200

PXL_20220629_233907548.jpg
 

JonFo

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An older Anthem AVR with ARC would make a good choice.
Used Anthem MRX 520's are going for <$600, and they have full ARC Genesis room correction support + HDMI ins (with 4K support), full pre-amp outs, no phono, but does have multiple analog inputs.
Hard to think of a better 2.1 capable 'pre-amp' with DRC than that for the money.
 

mikebecerr1258

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My current DBX recommended device is the current DriveRack Venu360.

Then you might be interested in the Dayton DSP unit that Brandon references above. Or if you want complete simplicity, this $500 active three-way crossover looks like quite the good value: K231 Stereo 3-Way Active Crossover

Just spec the values I referenced above for the Marchand unit.


Money no object, that Aurum Cantus AC300 I mentioned above. Otherwise the


or the Goldwood reference in that thread I just linked (and the OP has in his units).


Yes, find a model that already handles 2.1 and possibly includes room correction and save yourself some complications. But those can't get spendy. What's the budget range?
Often, using a great quality older model AVR as a pure preamp can be the answer here, as the video and surround processing sections become obsolete, yet the phono input, all analog processing, and control are still great quality, yet they sell for huge discounts. And because they have HDMI inputs, it's easy to hook up a streaming box such as the AppleTV (and edition) and play back lossless content from Apple Music.
You can even use a $30 HDMI splitter to send 4K video to the TV, and send a 1080p signal with the audio to the AVR. I use one in my HT rig to get Atmos audio, even though my video chain is 1080p for now.
An older Anthem AVR with ARC would make a good choice.

If you use a 2.1 capable pre, then the crossover for the Monoliths only needs to be a 2-way.
The Goldwood Sound Woofer fits the original Eminence Woofer cut-out perfectly! The Aurum Cantus is listed at 12.99" (? mm), which means you'd have to modify/enlarge the existing woofer cutout. Also want to ask your opinion of using the Parasound Halo P6 Preamp? It has outputs for One or TWO powered Sub-Woofers AND it has a Sub Output & Main Output variable XO!!! What in reality would these built in XO controls do for my system? And worst case scenario... would I not merely need a Preamp and 2-way XO's hooked up to Two individual Stereo Amplifiers with either 1 or 2 Powered Sub-Woofers for a superb 2.1 Stereo system??? In other words... no need for the DBX, Marchand, nor the Sublime Acoustics XO?
 

JonFo

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Also want to ask your opinion of using the Parasound Halo P6 Preamp? It has outputs for One or TWO powered Sub-Woofers AND it has a Sub Output & Main Output variable XO!!! What in reality would these built in XO controls do for my system?
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.

And worst case scenario... would I not merely need a Preamp and 2-way XO's hooked up to Two individual Stereo Amplifiers with either 1 or 2 Powered Sub-Woofers for a superb 2.1 Stereo system???

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.
 

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Just throwing this one out there to leave a complete trail of options for other readers of this thread.

DEQX, makers of high-end audio active speaker XOs and DRC are coming out with a revamped line, headed by what looks to be a mighty impressive unit called the Pre-8, capable of handling a three-way stereo XO and up to two subwoofers in a 2.2 config. With multiple analog and digital inputs. They are making their system even more usable by non-geeks and enhancing the XO blending with Cloud-based algorithms that should help achieve very low group delay around the XO region.
By actively measuring each half (or third) of the speaker system in your room, it sets the most appropriate XO points to assure good results. It then EQ's each output for flat frequency response.
Then it allows the user to perform a full Digital Room Correction measurement and adjustment to ensure the in-room performance of the 2.1 system as a whole is accurate. It supports custom target curves as well.

As of late July, 2022, no pricing announced, but my guess is it will be somewhere between $4K and $6K. Considering my DriveRack 4800 cost $5K over a decade ago, has a steep learning curve, and all it does is a 4x8 crossover (well, limiters, sub-harmonic, synth, EQs, etc.), the DEQX being a complete preamp as well makes that a reasonable deal.

deqx-gen4-hd-active-v2-cb.jpg
 

mikebecerr1258

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Just throwing this one out there to leave a complete trail of options for other readers of this thread.

DEQX, makers of high-end audio active speaker XOs and DRC are coming out with a revamped line, headed by what looks to be a mighty impressive unit called the Pre-8, capable of handling a three-way stereo XO and up to two subwoofers in a 2.2 config. With multiple analog and digital inputs. They are making their system even more usable by non-geeks and enhancing the XO blending with Cloud-based algorithms that should help achieve very low group delay around the XO region.
By actively measuring each half (or third) of the speaker system in your room, it sets the most appropriate XO points to assure good results. It then EQ's each output for flat frequency response.
Then it allows the user to perform a full Digital Room Correction measurement and adjustment to ensure the in-room performance of the 2.1 system as a whole is accurate. It supports custom target curves as well.

As of late July, 2022, no pricing announced, but my guess is it will be somewhere between $4K and $6K. Considering my DriveRack 4800 cost $5K over a decade ago, has a steep learning curve, and all it does is a 4x8 crossover (well, limiters, sub-harmonic, synth, EQs, etc.), the DEQX being a complete preamp as well makes that a reasonable deal.

View attachment 23050
Thanks for the info, but for someone still struggling with technology... being that you're already familiar with my Monolithiii setup... If I have a preamp along with TWO stereo amps, would the DBX 223SX Crossover be an effective solution to replacing the ML factory Passive crossovers?
 

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If I have a preamp along with TWO stereo amps, would the DBX 223SX Crossover be an effective solution to replacing the ML factory Passive crossovers?
I'll say no to this option for two reasons:
- Tech challenges, while no software is involved, there are many permutations of settings on that DBX that will give poor results.
- Gain management, as this unit uses Pro-level input and output levels, which are way higher than unbalanced 'consumer' levels. And while it has attenuators/gain controls, you'd have to crank up the input gain to the point where noise may be audible.

If simplicity and good audio quality are your goals, then nothing will come closer than the Sublime Acoustics XO discussed above. That thing is dead simple to use in a consumer audio system and a great value IMHO.
 

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@mikebecerr1258 now the question becomes: What preamp are your planning to use, the P6 ?

And, will the overall system be a pure 2ch or a 2.1 (with a sub) ?
 

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@mikebecerr1258 now the question becomes: What preamp are your planning to use, the P6 ?

And, will the overall system be a pure 2ch or a 2.1 (with a sub) ?
Okay, so here goes... I will probably purchase the Sublime Acoustic K231 Active XO. I would like your input on a total of 4 Preamps: Parasound Halo P6 (most expensive), Rotel RC-1572 MKII, NAD C165BEE, or Schiit Freya + (least expensive). I presently own ONE powered Sub-woofer (Polk PSW 505) and it is presently integrated into my system, making it a 2.1. How important is having a 2nd matched Sub-woofer and why? Do you have a favorite brand of Sub-woofer that won't break the bank? Opinion of SVS (it's a local Ohio company right here in my backyard). Also, please pay close attention to these preamps and their sub-woofer outputs, or lack thereof...
 

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Also, please pay close attention to these preamps and their sub-woofer outputs, or lack thereof...
And it is important to do so, as we'll see:

Halo P6 - Sub out is from a true crossover, with the main pre-out being affected as well.

Rotel RC-1572 Neither the marketing blurbs nor the owner's manual indicate if the sub-out has any crossover, nor the frequency or slope. So the conclusion is that it is just an L/R sum of the primary signal, and the main pre-out is never affected. Wierd for an otherwise nice piece of kit clearly designed in the past few years. On the plus side, it has MQA, and is a Roon-ready target (both require software on a PC to manage the tunes, but it can be as simple as the Tidal App).

NAD C165BEE Same problem as the Rotel, it's a summed L/R, but at least here, it is low-passed at (guessing) 80Hz as the spec is -3dB @ 100Hz. The main pre-out does not seem to be affected. So pass on this for 2.1 as well.

Schiit Freya + Nice little Tube Pre-amp, but it is strictly a 2Ch preamp, no subwoofer integration at all.


So the only preamp in the list above that has an actual usable 2.1 implementation with legit low-pass, high-pass crossover for a sub is the P6.
 

JonFo

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I will probably purchase the Sublime Acoustic K231 Active XO
Remember that there are options here that would allow the K231 to support a 2.1 configuration, even if the pre-amp is strictly limited to 2Ch outputs.

You can specify the K231 as follows for a 2.1 setup:

High out: High pass @300Hz
Mid out: Low pass @ 300
Low (sub) out: Low pass @80Hz summed L/R, both outputs live to feed 2 subs

The unit should be configured (by the vendor preferably) as a 2.1 with the high-pass of the low out feeding the mid out (creating a bandpass filter between 80 and 300Hz on the mid out), as explained in their manual. This is a bog-standard config, and the vendor will know what to do.

So for $520 you remove the need for the preamp to support 2.1, as in this config, the XO will handle all XO duties for the three sets of outputs to the amps.

That means the Schiit (or any other 2Ch only Pre) is an option.
 

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Remember that there are options here that would allow the K231 to support a 2.1 configuration, even if the pre-amp is strictly limited to 2Ch outputs.

You can specify the K231 as follows for a 2.1 setup:

High out: High pass @300Hz
Mid out: Low pass @ 300
Low (sub) out: Low pass @80Hz summed L/R, both outputs live to feed 2 subs

The unit should be configured (by the vendor preferably) as a 2.1 with the high-pass of the low out feeding the mid out (creating a bandpass filter between 80 and 300Hz on the mid out), as explained in their manual. This is a bog-standard config, and the vendor will know what to do.

So for $520 you remove the need for the preamp to support 2.1, as in this config, the XO will handle all XO duties for the three sets of outputs to the amps.

That means the Schiit (or any other 2Ch only Pre) is an option.
So my understanding is that as long as I purchase and incorporate the K231 XO into my 2.1 system, I can use ANY of those 4 Preamps described from an earlier thread??? And one of my 2-channel amps will handle the High out, while the other 2-channel amp will handle the Mid out?, with the built-in amps in the sub-woofer(s) handling the Low(sub) out? If I do go this route (which is my intention), then which of those preamps do you prefer, and why? Also, you may have missed my question regarding how important you felt it was to incorporate TWO matched subs, as opposed to a single sub. Ans finally, which sub manufacturers do you prefer, and why?
 

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I wrote to Sublime Acoustic but no response.
The one and only contact point is an email address for Marc. No phone number, no address. Last comment on their site blog 2+years old went unanswered.
I wonder if other people can chime in on this product and company.
 

JonFo

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So my understanding is that as long as I purchase and incorporate the K231 XO into my 2.1 system, I can use ANY of those 4 Preamps described from an earlier thread??
Correct, any 2Ch preamp; simply choose based on whatever criteria you want.

And one of my 2-channel amps will handle the High out, while the other 2-channel amp will handle the Mid out?, with the built-in amps in the sub-woofer(s) handling the Low(sub) out?
Correct.
On the subs, you use the 'LFE' input if it has one.

If I do go this route (which is my intention), then which of those preamps do you prefer, and why?
It's your system, so now that the constraint regarding .1 support is removed, you are free to choose based on your needs.
That said, all of them are good units. I use a pair of Schiit products in my office Electrostatic headphone setup.

My idea of the perfect preamp (for me) is the Trinnov Altitude32, so about as far away from an analog 2ch pre as possible ;)
Also, you may have missed my question regarding how important you felt it was to incorporate TWO matched subs, as opposed to a single sub.
Most rooms benefit from 2 correctly located subs. If you are not willing or able to locate them in the best positions, then stick to one.
Research (Harman multi-sub presentation) has shown that for 2 subs, center-front and center-back are ideal (that's how my HT is set up), but they document some other placement options that also work.

Ans finally, which sub manufacturers do you prefer, and why?
Hum, I have been DIY'ing my big subs for 15 years, and the most recent commercial subs I purchased were the 4 ML Dynamos in the media room.

I'm a fan of the ML BP212 & BP210 subs, but other more modest subs in their lineup are good as well.
Plenty of other options out there, but since I don't shop for those, not a good reference source.
 

JonFo

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I wrote to Sublime Acoustic but no response.
Yeah, that's worrying, I scanned DIYaudio, and others are reporting the same.
Must be a one-person show and they are either not responsive enough or have moved on.

Mike, I'd proceed with caution, only order once you'd established contact. And possibly, time to look for alternatives (Marchand is always one).
 
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