Monoblock amps with ML speakers ? Advantage or not?

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likes2hike

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I am looking for a new amp for my Odysseys (or possible upgrades to 11A or 13A speakers)

Have owners found any significant advantages to using mono-block amps with these electrostatic speakers and do electrostatic speakers offer more (or less) of a reason to consider mono-block amps due to their varied impedance or some other factor?

Would mono-block amps be perhaps of more benefit in older speakers (like the Odysseys) that do not have powered woofers inside, and therefore would the newer line of speakers perhaps benefit less from mono-block amps as they have powered woofers?

Are there other factors that have caused owners to choose mono-block amps?

Thanks.
 
Good question and one that will get various answers. Would mono blocks be a better match for older non-hybrid speakers ? My answer is , it depends ! So long as you keep it apples to apples. Don't try and compare a $500 100 watt AVR to a pair of PASS X260.8's
On the other hand will the X260.8's outshine a single X350.8 ??

I've owned mono blocks for the past 9 years (Rogue M180's and now PASS X260.8's) and while I have no plans to abandon my current set up I can honestly say that when my Spires years ago were driven by my lone Plinius SA-102 it was pure heaven
 
Thanks for the helpful response. I should be more specific.

At this point, I have listened to the Pass X250.8 with the XP-12 pre-amp but am wondering if a pair of Pass X260.8 mono-blocks would make much more NOTICEABLE difference, either with my current Odysseys or (even more or even less of a difference) with the 11A or 13A speakers if I choose to upgrade the speakers.

Or, perhaps, moving up to the Pass XP-22 pre-amp may provide for a more noticeable difference than moving to mono-blocks?
 
While the X260.8's offer more initial bias into Class A my 'gut' is telling me you probably would not notice much, if any difference. Remember, it would take a doubling of power just to gain 3db.

I'm assuming it would not be possible to do a side by side comparison. As for the pre upgrade, my gut tells me the same thing.

If your room can support it size wise the 13a's are the sweet spot in the line up IMO
 
Thanks for the helpful response. I should be more specific.

At this point, I have listened to the Pass X250.8 with the XP-12 pre-amp but am wondering if a pair of Pass X260.8 mono-blocks would make much more NOTICEABLE difference, either with my current Odysseys or (even more or even less of a difference) with the 11A or 13A speakers if I choose to upgrade the speakers.

Or, perhaps, moving up to the Pass XP-22 pre-amp may provide for a more noticeable difference than moving to mono-blocks?

I have had the XP-22 for roughly two months now and have to admit it is a good step-up from XP-12. We are talking more refined texture, space, separation of instruments/vocalists, etc. You are going to benefit more if you go with the XP-22. I have the XA30.8 amp and it is a joy to listen to and both the amp/preamp make wonderful music. I can say with certainty that I will not upgrade these further. My future disposable income will be spent on a very nice DAC and upgrading my ML Theos.
 
It's not the ESL portion of Odyssey that's the problem for any amp, it's the passive bass xo. So go active in the bass only, and they'll sound as good as the new ones.
Can you explain further? Specifically how would I go active in the bass only?

Also, is there much diffference on the newer crossovers vs. what I have and if so, is that something I can “upgrade” or improve on keeping my current speakers?
 
Or at least take advantage of bi-amping. Then a nice small class A amp can be used on top, and big ugly-sounding multi-transistor amp on bottom. Divide and conquer!
Just read the manual for the Odysseys again. That is something I don’t know anything about and never considered . I’m definitely intrigued.

Can you elaborate more on what bi-amping would improve on sonically assuming that regular wiring with a Stereo amp would be a Pass 250.8 (Which should have enough power for the ESL portion and woofers)?

I looked at the new ESL13A speakers again last night and definitely prefer the wood trim on the Odysseys I have now, as does my wife :) , so I’m thinking harder about whether I can further improve the pair of speakers I currently have.

Your comments are much appreciated.
 
I am not sure how much your budget is. But if you are going to buy the 13A, you will not require a lot of power since the speakers are powered. So, unless you have a very generous budget, I would go with a humble XA30.8 or XA60.8 mono blocks. You will have that sweet class A on tap to make you grin ear to ear. You can then go for the XP 22 or even better, XP 32 which will really make a huge difference in audio refinement. Pass and ML are a match made in heaven!
 
I am looking for a new amp for my Odysseys (or possible upgrades to 11A or 13A speakers)

Have owners found any significant advantages to using mono-block amps with these electrostatic speakers and do electrostatic speakers offer more (or less) of a reason to consider mono-block amps due to their varied impedance or some other factor?

Would mono-block amps be perhaps of more benefit in older speakers (like the Odysseys) that do not have powered woofers inside, and therefore would the newer line of speakers perhaps benefit less from mono-block amps as they have powered woofers?

Are there other factors that have caused owners to choose mono-block amps?

Thanks.
I used to drive my Odysseys with NuForce Ref 9 class D mono blocks for years - and got a Descent I to give good bass. I thought it all sounded great, until I got a (used) Krell 2250 amp. It brought new live to my 16 year old MLs, I actually think I don't need the subwoofer anymore (for music). I listened to the 11A and 13A too, and although they sound fantastic, the cabinets look too deep (shape wise) for my living room.
 
Or at least take advantage of bi-amping. Then a nice small class A amp can be used on top, and big ugly-sounding multi-transistor amp on bottom. Divide and conquer!
^^^ This!

Super-simple, just make sure the second amp has gain controls, as you will be to match overall gain to the amp driving the panels (most Audiophile amps lack gain controls).

I also second the notion of going active on the bass segments. Many pro-audio amps have built-in XO / EQ functions, so get one of those and it's all in one box. Crown XLS DriveCore 2 series are a good option (they have selectable input sensitivity and RCA inputs), with no passive in the way, 200wpc is plenty, but I'd go for the 300wpc XLS 1502.
 
also long article here about bi-amping:
https://sound-au.com/bi-amp.htm
These ML ESL hybrids combine two 'opposite' loads in parallel: the ESL panel and passive xo via the audio step-up transformer 'prefers' to be driven by voltage from an amp, while the bass woofer and passive xo 'prefers' to be driven by current.
 
Converting to active xo on passive ML hybrids that use two woofers which receive different freq ranges (like Odyssey and Prodigy) will need a two-way active xo on the bass to recreate the two stock passive xo's in those (and also require another amp and set of binding posts). The ESL portion stays passive with its OEM xo and eq.
So not as simple as converting a single-woofer SL3 or Ascent to active bass xo....
 
Converting to active xo on passive ML hybrids that use two woofers which receive different freq ranges (like Odyssey and Prodigy) will need a two-way active xo on the bass to recreate the two stock passive xo's in those (and also require another amp and set of binding posts). The ESL portion stays passive with its OEM xo and eq.
So not as simple as converting a single-woofer SL3 or Ascent to active bass xo....
Correct, I forgot those two models have dual bass drivers.

What we need is for someone technically proficient to grab an XLS and configure it for driving a dual-woofer model and then post the settings.
The physical aspects of this would seem straightforward, even adding an extra set of speaker terminals.

It does mean those models need an XLS per side. But at $450/ea, not going to break the bank, that's for sure.
 
Attached is simplified Prodigy bass xo with some of my notes.
 

Attachments

  • ML Prodigy bass xo simplified1.png
    ML Prodigy bass xo simplified1.png
    5.8 MB · Views: 15
I am looking for a new amp for my Odysseys (or possible upgrades to 11A or 13A speakers)

Have owners found any significant advantages to using mono-block amps with these electrostatic speakers and do electrostatic speakers offer more (or less) of a reason to consider mono-block amps due to their varied impedance or some other factor?

Would mono-block amps be perhaps of more benefit in older speakers (like the Odysseys) that do not have powered woofers inside, and therefore would the newer line of speakers perhaps benefit less from mono-block amps as they have powered woofers?

Are there other factors that have caused owners to choose mono-block amps?

Thanks.
Have been using a pair of mcintosh mc301 mono blocks with a pair of Classic ESL 9's. Considered these as Pass was not available without pre-order and much waiting time and also due to the ability of the amps to handle impedence swings in the ESL's, mcintosh autoformers had it covered.

Loving the sound. Crisp transparent and fantastic sound stage.

For me, Why go did I go monoblock? my current reasoning (which may change with time and speakers haha) - "Control".

A good monoblock from Mcintosh or Pass or similar manufacturer offers a lot of control and discreet channel performance that I audibly prefer. Others opinion may differ here and that is fair. You will really have to hear the speakers and it depends how you are going to set them up. ESL's given the right setup and are like having a grand piano and a maestro in the room all day everyday. The 11 or 13 are powered and definitely require less power to push bass drivers in the woofers but those panels need control if you want to see them do the magic they do. Depending on your room size and setup a modest class A Pass integrated or mcintosh integrated autoformers would do well too. Whatever you do chose, it should be able to handle down to 2ohm loads to control these panels correctly.
 
On similar points as mentioned above, I had short listed 5 types of speakers in 2018; CLX's, Ren15a's, Avant Garde Duo XD's, Audio Analysis Omega's and refurbed Apogee's.

Since I finalised on the CLX's and my listening sessions are way past midnight (it's now 1:30am as I'm typing this...) I needed amplifiers that deliver the full sound at soft to moderate levels, without blowing the roof off and waking up the household... tubes do that for me, and I absolutely love the special kind of synergy tubes have with full range stats.

Although my CJ monoblocks are rated at 125-150w of Class AB power, I got them upgraded to the full SE version and modded their Class A bias output to 60w. This project took nearly two years to complete, and was finally done only around March of last year. It took a lot of skill and knowledge to do these kinds of mods and did cost me quite a pretty penny...

At the end of the day, it was fully worth the time and effort. Now, these CJ monoblocks fully grip the CLX's effortlessly even on the softest passages and has an enveloping affect to the sound, not just the warmth and expansive sound stage that tubes offer but much more.

So, in my particular setup, these monoblocks are an ideal match for my listening tastes and listening habits, plus preferences in listening distance. If I were to have gone with a single stereo amplifier then I would have to spend quite a lot more in order to find a pretty large tube amp that can handle the CLX's full range. And CJ tube amps in Aus are very pricey, they start at 16grand upwards...

In your case, you would need to consider the following:
1. Listening tastes and habits.
2. Personal preference in listening distance.
3. Room size and speaker location.

Once you've clearly determined these three basic elements then you'll know whether or not your system requires monoblocks. Only you can determine this, simply because it's your room and your ears!

All the best, RJ
 
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