Expression 13A Speakers – Predictions Please - and Questions

[Hear Here]

I’ve just ordered a pair of Expression 13As and would greatly appreciate ML owners’ predictions of how they may sound in my odd-shaped room and with my available amplifiers.

Firstly the room - It’s roughly semi-circular (more parabolic), just under 1000 sq ft but with low 7’7" ceilings. Floors are timber boards on concrete with about 30% carpeted. Curved walls are mostly floor-to-ceiling glass (offering great sea views) and the speakers will be in the middle of the room, either side of a column and facing across the room. So there’s 10 – 15 ft behind the speakers. Curtains are always left open.

Amplifiers - I have:

NAD Master Series M32 - 150 watt integrated
Micromega M100 – 100 watt integrated with MARS room correction
GamuT D200 – 200 watt MOSFET power amp
Accuphase A-36 – 30 watt Class A power amp
Consonance Cyber 845 monoblocks – 28 watt tube SET
(Last 3 controlled by NAD M12 preamp, or line out from M32)​

My outgoing speakers are Avantgarde Uno horns (bought new in 2003 after being voted Stereophile “Speaker of the Year” in 2000) which I normally power with the NAD M32 set to low gain, although the 845 SET monos are exceptional too. I had Quad 2905s (with 2912 mods) for a short while. They sounded great but unacceptable owing to their “barn door” presence in the middle of my room. However, these prompted me to go for the semi-transparent and much slimmer MLs. I’m hoping the choice of 13As will be good for the next decade or two!

Which amplifier do you predict will sound the best, or which alternatives do you think I should consider? I need to sell the others to fund the new MLs!

I'm planning on placing the speakers on the same slate slabs (24"x16"x1") as I use for the AGs, with carpet tiles beneath although I'd like to change these carpet tiles for more effective sound insulators. Any suggestions for under-speaker materials?

Lastly do you think the recommended toe-in (reflection from 1/3 from inside edge of panel) will suit my circumstances?

Thanks. Peter

 

[ttocs]

I'll take a stab at the room and speaker setup, don't know anything about those amps.

Hopefully, the speakers will aim at the "short" distance of the parabola ?? If aimed the long way, I would think the sound would get bunched up behind the seating area and could get ugly.

The low ceiling may be a problem for bass, but those new speakers will probably be able to tame this issue with the room correction software built-in.

Having that great amount of space behind the speakers is just that, great! I've found that room issues diminish when going over to the dark side, nearfield. I'm slightly nearfield - 9-1/2' seat to speakers and 10-1/2' between speakers, and it's wonderfuller than I could imagine. Currently I'm only using two absorption panels on front wall for the first reflection of the left and right front speakers, and one panel on the one side wall first reflection close to one speaker, the other side wall is way far away. Also, I found that my speakers are slightly more than the 1/3 toe-in. This brought the soundstage together really, really, well. When I experimented with the toe, it went from less than 1/3 and sounding weak, to 1/3 and sounding great, to more than 1/3 and sounding spectacular!

These are just my thoughts. Looking forward to reading the thoughts of others. Congrats on the new speakers!! Those are the ones I would get if I could upgrade now.

 

[Hear Here]

I'll take a stab at the room and speaker setup, don't know anything about those amps.

Hopefully, the speakers will aim at the "short" distance of the parabola ?? If aimed the long way, I would think the sound would get bunched up behind the seating area and could get ugly.

The low ceiling may be a problem for bass, but those new speakers will probably be able to tame this issue with the room correction software built-in.

Having that great amount of space behind the speakers is just that, great! I've found that room issues diminish when going over to the dark side, nearfield. I'm slightly nearfield - 9-1/2' seat to speakers and 10-1/2' between speakers, and it's wonderfuller than I could imagine. Currently I'm only using two absorption panels on front wall for the first reflection of the left and right front speakers, and one panel on the one side wall first reflection close to one speaker, the other side wall is way far away. Also, I found that my speakers are slightly more than the 1/3 toe-in. This brought the soundstage together really, really, well. When I experimented with the toe, it went from less than 1/3 and sounding weak, to 1/3 and sounding great, to more than 1/3 and sounding spectacular!

These are just my thoughts. Looking forward to reading the thoughts of others. Congrats on the new speakers!! Those are the ones I would get if I could upgrade now.

Thanks ttocs

The speakers face ACROSS the room from the centre - not towards the parabolic point, nor away from this point. I'll try to add a photo. It shows my AG horns close to the mirrored column, plus a pair of loan speakers outside the Unos. The table with other equipment was a temporary platform for alternative amps, so a bit messy that day! Peter

 

[amey01]

Which amplifier do you predict will sound the best,

Most people would kill to be able to own all these amplifiers and be able to try for themselves.

There's your answer.

 

[JonFo]

Regarding room setup, you actually have a decent enough location, with the wide open space behind the speakers, the 'front wall' reflections are going to be quite muted and very distinct from the main wave from the front of the ESLs.
No side-wall issues either, as both are far enough away.
Low celing can be dealt with my ensuring the rake of the ESL panel is vertical, and if necessary, raised in height to be covering your head while sitting.

As for amps, my bet is the NAD Master series will be the most accurate of the bunch. Its direct digital drive is adaptable to load and preserves the additional timing accuracy of an MQA signal.

The GamuT has more power, and on paper seems to deliver tons of current, but the output stage is very sensitive to the capacitive and low-impeadance of ESLs. Definetly use the filtered output when testing that amp on the Expression 13A.

The Accuphase lacks the power to drive the ESLs to their max dynamics. The prior owner of my Monoliths demoed them to me with his 50Wpc class-A Accuphase, I was underwhelmed, and it clipped.

I personaly do not think tubes are a good match for ELS (unless you are doing a 200W high-voltage ESL panel direct-drive thing that can fry you like a fly if you mess up), so the SET is definetly out in my book.

I hope that helps.

 

[Hear Here]

Low celing can be dealt with my ensuring the rake of the ESL panel is vertical, and if necessary, raised in height to be covering your head while sitting.

As for amps, my bet is the NAD Master series will be the most accurate of the bunch. Its direct digital drive is adaptable to load and preserves the additional timing accuracy of an MQA signal.

The GamuT has more power, and on paper seems to deliver tons of current, but the output stage is very sensitive to the capacitive and low-impeadance of ESLs. Definetly use the filtered output when testing that amp on the Expression 13A.

The Accuphase lacks the power to drive the ESLs to their max dynamics. The prior owner of my Monoliths demoed them to me with his 50Wpc class-A Accuphase, I was underwhelmed, and it clipped.

I personaly do not think tubes are a good match for ELS (unless you are doing a 200W high-voltage ESL panel direct-drive thing that can fry you like a fly if you mess up), so the SET is definetly out in my book.

I hope that helps.

Thanks Jonathan - very helpful. I could of course be patient and wait till the beast arrive, but your feedback is most welcome.

The 13A seems to have a bigger slope than the 15A which has an almost vertical panel. From what you say, I may need to use taller spikes at the rear of the enclosures.

I hope you're right about the NAD amp. It would make a much neater solution (with just the matching M50.2 completing my electronics) than the other amps I have.

I do love the GamuT - it has real grunt, though sometimes I think a bit too much - with my Avantgardes in any event.

I was hoping I'd love the Accuphase with my AGs but it is somehow a little "soft" despite having far more power than is necessary for these 102dB speakers. You comment seems to confirm that this splendid amp won't be ideal with the new MLs.

Similarly the 845 amps. I used them for several years (and other tube amps - Art Audio PX-25 and Carissa), but I concluded that I wanted to move to SS. That's really why I have 5 significant options.

If the NAD lives up to expectations (I suspect the GamuT will give it serious competition), I'll be happy to sell all the others. These sales (plus the AG horns) will offset the huge ML investment.

I don't think the MLs will arrive until the New Year - can't wait!

Peter

 

[timm]

Awesome!! Have fun. It’s about the journey. Let us know how it all shapes up. What’s the pre amp on your non integrated?

 

[Hear Here]

Awesome!! Have fun. It’s about the journey. Let us know how it all shapes up. What’s the pre amp on your non integrated?

Thanks - I certainly will report back. See my initial post re preamp - "Last 3 controlled by NAD M12 preamp, or line out from M32". I could use either as a preamp if a power amp proves best, although the M12 has balanced out so perhaps the better choice. Peter

 

[patsuh]

I’ve just ordered a pair of Expression 13As and would greatly appreciate ML owners’ predictions of how they may sound in my odd-shaped room and with my available amplifiers.

Firstly the room - It’s roughly semi-circular (more parabolic), just under 1000 sq ft but with low 7’7" ceilings. Floors are timber boards on concrete with about 30% carpeted. Curved walls are mostly floor-to-ceiling glass (offering great sea views) and the speakers will be in the middle of the room, either side of a column and facing across the room. So there’s 10 – 15 ft behind the speakers. Curtains are always left open.

Amplifiers - I have:

NAD Master Series M32 - 150 watt integrated
Micromega M100 – 100 watt integrated with MARS room correction
GamuT D200 – 200 watt MOSFET power amp
Accuphase A-36 – 30 watt Class A power amp
Consonance Cyber 845 monoblocks – 28 watt tube SET
(Last 3 controlled by NAD M12 preamp, or line out from M32)​

My outgoing speakers are Avantgarde Uno horns (bought new in 2003 after being voted Stereophile “Speaker of the Year” in 2000) which I normally power with the NAD M32 set to low gain, although the 845 SET monos are exceptional too. I had Quad 2905s (with 2912 mods) for a short while. They sounded great but unacceptable owing to their “barn door” presence in the middle of my room. However, these prompted me to go for the semi-transparent and much slimmer MLs. I’m hoping the choice of 13As will be good for the next decade or two!

Which amplifier do you predict will sound the best, or which alternatives do you think I should consider? I need to sell the others to fund the new MLs!

I'm planning on placing the speakers on the same slate slabs (24"x16"x1") as I use for the AGs, with carpet tiles beneath although I'd like to change these carpet tiles for more effective sound insulators. Any suggestions for under-speaker materials?

Lastly do you think the recommended toe-in (reflection from 1/3 from inside edge of panel) will suit my circumstances?

Thanks. Peter

Peter you have a gamut amplifier this is a stunning piece to drive a pr of ml, we listened one with clxs and are amazing, best bass response from clxs we have heard


Enviado desde mi iPad utilizando Tapatalk

 

[Hear Here]

FWIW, the speaker that pulled me away from Logan was the Revel Studio2, but that was before I listened to the 13A's ..........

[Quote from a fellow 13A owner and taken from another thread]

You'll have to let me into the secret of getting the 13As to sound as good as I think they're capable of - and sounding better than the Revels.

I bought my 13As a few weeks ago, but have held fire on expressing an opinion until there were well run in and I've become accustomed to them. Sadly, I'm most disappointed.

I tried my existing collection of amps*, but not a good sound was heard! Following the many users here that speak very well of the Sanders Magtech amp, I bought one last week - better but not there yet!

I've kept my Avantgarde Uno Series II speakers (Stereophile's Joint Speaker of the Year 2000) and can switch between the two systems. So far, the Avantgardes undoubtedly sound better, although there's perhaps a little more top detail with the 13As. Others who have listened agree - the MLs are disappointing. The MLs tend to screech at high volume and they seem to have a big gap where the richness and fullness of music is missing. I don't want over-warm, but music must be comforting and encourage a smile on one's face - as live music does! There's no "tingle factor" - yet at least.

Any suggestions? My room (illustrated above) is large, speakers have 12-15 feet behind them and are 10 feet from side walls. I'm using the 1/3 torch reflection toe-in as recommended, but have experimented with more and less toe in. This changes the imaging but not the overall impression that the reproduced recorded music is far short of its original live performance.

Incidentally Revel Studio 2s were on my wish list but I settled for the MLs. Peter

* Amplifiers used:
GamuT D200 Mk III
Accuphase A-36
NAD M32
Micromega M-100
Sanders Magtech (bought specifically for the MLs)

 

[roni44]

I have Micromega M150 for last 2 weeks as a loan from distributor, I thought it did a wonderful job on my Clarity against my Primare integrated especially after room correction. Since I have a very difficult room with floor to ceiling windows behind the speakers and tile floor, with room correction did the trick of getting Clarity sound the way it should be, only complaint I have was bass responses wasn't as good as Primare. Maybe let your 13A burn-in a little more to see if the sound improves and use the room correction few more times.

 

[mac_tweety]

Hi Peter,

I run either a Mcintosh MC601 or 2 pieces MC275 in mono on my expression. I have to say it sounds very good (see system 466).
The Expression need some time for break in (at least 100 hours).

 

[James]

I did not like the Macintosh PowerAmp with my ESL15's. The Sanders Magtech was noticeably better as I see you bought one.. Playing with Positioning also helped quite a bit. I was initially disappointed with the speakers, they do take awhile to break-in.

System 538.

 

[asindc]

With an open space that large, the more powerful and dynamic the amps, the better. Especially moving from the much higher sensitivity horns.

 

[Hear Here]

I have Micromega M150 for last 2 weeks as a loan from distributor, I thought it did a wonderful job on my Clarity against my Primare integrated especially after room correction.

I run either a Mcintosh MC601 or 2 pieces MC275 in mono on my expression. I have to say it sounds very good (see system 466).
The Expression need some time for break in (at least 100 hours).

I did not like the Macintosh PowerAmp with my ESL15's. The Sanders Magtech was noticeably better as I see you bought one.. Playing with Positioning also helped quite a bit. I was initially disappointed with the speakers, they do take awhile to break-in.

System 538.

Thanks Roni, Mac and James

My Micromega sounds good but (with the 13As) is bettered by some of my other amps. The Room Correction may improve the 13A sound, although probably won't prevent clipping which I think contributed to its problems. Incidentally the Micromega powering Focal Supra 2 speakers was selected by Stereophile as "best sound in show" at RMAF last year. It's a great amp but (certainly the M100) probably not quite up to the demands of the ESLs.

I'd rather not go the tubes route, although I notice a number of Mac 275s in ML owners’ systems. I moved away from tubes with my horns 5 years ago and not regretted the move once the right SS amp was installed.

Interesting that James has the choice of Mac 275 and Sanders Magtech. This is encouraging as my Magtech certainly offers the best sound of all my amps with the 13As - thank goodness, as it was bought (used) last Friday specially for the MLs!

I've been running the speakers for probably between 2-300 hours so far. The difference is still so big that pink or white noise for example sounds vastly different through my 2 systems.

It's all really odd because I've had 2 other good speaker systems in my room over the last couple of years that offered a sound so similar to the Avantgardes as to render the differences hardly noticeable. These were cone and ribbon Quadral Montan 8s and ESL Quad 2912s. In fact it was my experience with the delightfully sounding (but aesthetically far less so) Quads that encouraged me to go for Martin Logan.

Switching speakers on music with a solo singer for example moves the singer from quite close to me to a position a significant distance away, although increasing the 13A's toe-in seems to bring them forward a bit. The precise position of the singer is a bit vague with the MLs to the extent that I've double-checked speaker phasing 3 times to ensure I have all positives to positives! But again increasing toe-in to about 40% (compared with the recommended 33%) improves imaging.

One other idea I'd appreciate your opinions on - the MLs are 10 ft apart and my listening chair is 14 feet from the speakers, so well within the recommended positioning. The Avantgardes are inside the MLs so 8 feet apart with the same 14 feet to listening position. The AGs are toed-in even more than the MLs - possibly equivalent to 45%, so nearly straight towards the listening position. Would the MLs be better closer together?

Tilt - I've raised the back of the MLs so the angle of tilt is more like 2-3 degrees rather than the default 5 degrees. What tilt do you find best? 15As are vertical - I wonder if the 13As should be too. Or do you prefer the "laid back" approach?

I'm still determined to find the answer to getting my MLs to sing, but I'm struggling right now. I'm hoping some more visitors who have greater ESL experience than me will be able to offer fresh ideas, but I'm now convinced that the amplifier is not to blame. On a positive note, the MLs sound much better than the horns when I’m behind the speakers – in my dining or kitchen areas!

Peter

 

[roni44]

M100 only rated @100w/8ohm and 200w/4ohm which still might be under power for 13As, maybe give M150 a try which is more than I need for my Clarity. I have owned just about every pair of ML during the 90s, and they do sound the best at vertical to me.

 

[mac_tweety]

I did not like the Macintosh PowerAmp with my ESL15's. The Sanders Magtech was noticeably better as I see you bought one.. Playing with Positioning also helped quite a bit. I was initially disappointed with the speakers, they do take awhile to break-in.

System 538.

Unfortunately , Sanders Magtech are not available in Germany for testing. I listened to the Renaissance at my dealer's with Mcintosh MC601 and it sounded very good.

 

[Brad225]

HH, I would think the Sanders would be your choice though I am not familiar with all of your amp choices.

The AG's and the ML's are going to sound very different. I like AG alot just like ML better.

I have much respect for Jon's opinion, though I think ML's can sound amazing with tubes.

From your pictures the TV and equipment between speakers is hard for speaker imaging. I would try bringing the ML's a bit closer together and be sure you are listing to the proper part of the panel.
As far as tilt this is what I have found provided the best sound in my rooms.

I have adjusted the tilt from original of any of the 6 pairs of ML's I have owned. I will depend on your seat height and distance from your speakers to your ears.

I believe you want to be listening to the vertical center of your panel. This way you will receive a more even wave of sound from the entire panel since it will reach your ears at closer to the same time. If you have more forward or back tilt you will be listening to more of the top or bottom of the panel.

I take a carpenters framing square that has one 16" leg and one 24" leg and place one leg against the vertical front of the panel. It is fairly easy to see where the center of the panel is pointing in relation to the height of your ears in your listening position. Then adjust the tilt accordingly.

I only use the square to adjust one panel tilted to focus the center of the panel at my ear height. I then sight the speakers in relation to each other from the side. I adjust the second speaker to have the exact same tilt as the first. I think this is much more accurate then trying to do it with the square a second time.

This has given me the best sound. YMMV

Let us know how things progress.

 

[ttocs]

Thanks Roni, Mac and James

I've been running the speakers for probably between 2-300 hours so far. The difference is still so big that pink or white noise for example sounds vastly different through my 2 systems.

Switching speakers on music with a solo singer for example moves the singer from quite close to me to a position a significant distance away, although increasing the 13A's toe-in seems to bring them forward a bit. The precise position of the singer is a bit vague with the MLs to the extent that I've double-checked speaker phasing 3 times to ensure I have all positives to positives! But again increasing toe-in to about 40% (compared with the recommended 33%) improves imaging.

One other idea I'd appreciate your opinions on - the MLs are 10 ft apart and my listening chair is 14 feet from the speakers, so well within the recommended positioning. The Avantgardes are inside the MLs so 8 feet apart with the same 14 feet to listening position. The AGs are toed-in even more than the MLs - possibly equivalent to 45%, so nearly straight towards the listening position. Would the MLs be better closer together?

Tilt - I've raised the back of the MLs so the angle of tilt is more like 2-3 degrees rather than the default 5 degrees. What tilt do you find best? 15As are vertical - I wonder if the 13As should be too. Or do you prefer the "laid back" approach?

I'm still determined to find the answer to getting my MLs to sing, but I'm struggling right now. I'm hoping some more visitors who have greater ESL experience than me will be able to offer fresh ideas, but I'm now convinced that the amplifier is not to blame. On a positive note, the MLs sound much better than the horns when I’m behind the speakers – in my dining or kitchen areas!

Peter

My current Vistas are about 10' apart and I sit 9-1/2' away, slightly nearfield, toe is a little less than yours but more than 33%. The stage is great. I discovered that the singer, and other middle band members, are distant with less toe, and closer with more toe. The bottom line, adjust to taste so the band is distributed to your liking.

My Vistas are almost vertical. I use a framing level and measure the gap between top of the level to panel. With the level placed at the bottom of the panel, and measuring at the top of the panel, there's 1/8" gap to the level. I despise 4 feet on speakers so I drilled a hole for the "third foot" on the Vistas, much easier to adjust tilt with full weight on all 3 feet. With 4 feet there's the problem of uneven weight distribution and it's more tedious to get right than I'm willing to cope with. I'm OCD.

I just ordered 13A's! and they'll arrive on Monday, so I'll be catching up to you next week. I expect the Krell to handle things as usual.

 

[Hear Here]

Unfortunately , Sanders Magtech are not available in Germany for testing. I listened to the Renaissance at my dealer's with Mcintosh MC601 and it sounded very good.

Give Roger Sanders a call in US. Bizarrely, you'll have to key in your own phone number (omit the 0) before incoming calls are accepted. Once you're through, you'll find an enlightening attitude to marketing audio equipment. He couldn't be more helpful and will offer to send you a new amp (yes, to Germany, as he offered to send one to me in UK) free of carriage charges. If you're not happy, he'll pay for the return carriage too. Can't be better than that!

I found a rare used Magtech here in UK (probably one of only a handful in the country) and Roger offered valuable advice on what to look out for in a used amp. Again, which other manufacturer will admit that a small number of his amps had transistors from an unreliable batch? If one of these transistors fails, he'll replace the boards - again without charge.

I have a selection of excellent amps (listed above) but the Magtech is the best of the lot with ML speakers. Good luck.