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Other Stuff => Archived Manufacturer Circles => Music Reference => Topic started by: tdinut on 22 Jun 2014, 02:52 pm

Title: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 22 Jun 2014, 02:52 pm
I know this can be dangerous, but I'd love some real world recommendations for speakers that mate well with Roger's RM-10 MK II 25 watt amp.


I know that one usually picks speakers first and then a matching amp but I just had to have this amp.


Thanks!


Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Clio09 on 22 Jun 2014, 04:04 pm
Obviously your budget or listening tastes are going to play into this but I use the Audiokinesis Jazz Modules (original with TAD drivers). Furthermore, even though the speakers have a minimum 8 ohm load and pretty much operate in the near 10 ohm range I use the 4 ohm tap on the RM-10. Roger refers to this as light loading and it is certainly beneficial in my experience. I am also looking for a nice set of Quad ESL-57s for this amp. IIRC Roger built the RM-10 for use with his own ESL-57s.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: pehare on 22 Jun 2014, 04:05 pm
For several years now I've used & am quite happy w/Coincident Partial Eclipse II's (92dB, 7.9-10 ohm, 3 ways) w/my RM10 MKII (35 watt version) light loaded on the 4 ohm taps (which is probably close to the output on your new amp's 8 ohm taps).   Enjoy!
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: nnck on 22 Jun 2014, 04:37 pm
Hi again Joe.
So as you know, the amp I am using is a Music Reference RM-200II. I have it paired with Daedalus DA 1.1 speakers that are 97db efficiency and it's working quite well, as you would expect. Obviously, the RM-200II is a different amp than you are asking about, but with the high efficiency of Daedalus speakers it is reasonable to think that the RM-10 would work as well. In fact, when I first contacted Music Reference and went over the specs of my system, Ben (who works with Roger) first suggested I try the exact amp you are getting now. In the end to me, it amounted to a bit of a toss-up as I figured either amp should work well with my speakers. One deciding factor for me (although perhaps not an extremely important one) was that the RM200II could use a wider range of output tubes including 6550, KT88, KT120, EL34. Since this was my first ever tube amp, I thought the flexibility in output tubes might be a fun option to keep open. FWIW, I am also experimenting with light-loading on this amp, currently using the 2-ohm taps.

Anyway, the point of my post is mention Daedalus speakers as a possibility that might work well. There is quite a bit of info about Daedalus on the AC forums.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: jtwrace on 22 Jun 2014, 05:39 pm
Ben (who works with Roger)
He seems like a nice guy.  What's his position at MR?
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: mick wolfe on 22 Jun 2014, 05:48 pm
Having owned RM10's way back when, I would look at something that's seriously efficient. Within a reasonable budget, the Tekton Lore series deserve a look. Any of the three would be excellent starting with the M-Lore at around $700. Beyond that, perhaps the Audio Notes or even the Cornscala for even more headroom. Lots of good choices, but I would look most seriously at speakers with benign impedance curves and an honest 92db and above in efficiency...... if you want to listen to a wide variety of music.  As always YMMV, but this was my experience with the older versions of the RM 10. 
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: mick wolfe on 22 Jun 2014, 05:56 pm
If your budget is on the higher side,  Daedalus (which have been mentioned already)  and dc 10 should be on your radar.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: opnly bafld on 22 Jun 2014, 05:59 pm
He seems like a nice guy.  What's his position at MR?

http://www.audiocircle.com/index.php?topic=120165.0



When I had a RM10 many speakers paired well (even the 85 dB SP-BS22-LR), so I would say anything around 87dB and up.

I have bought an amp first and then searched for speakers several times, a lot of fun me thinks.  :green:

Lin
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: bdp24 on 22 Jun 2014, 06:55 pm
There are a nice used pair of GR Research Super-V on their AudioCircle section. Great speaker---Efficient Co-Ax (97dB sensitivity) from 280Hz (I think) up, powered OB Servo Subs below.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: OzarkTom on 22 Jun 2014, 07:17 pm
If your budget can reach this, get the Vaughn Triodes with the plasma tweeters. All of the reviewers at RMAF last year raved about these speakers, and this amp will work very nice. Ask Roger about these speakers, he has heard them.

http://www.vaughnloudspeakers.com/Speakers.php
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: sunnydaze on 22 Jun 2014, 07:46 pm
If your budget can reach this, get the Vaughn Triodes with the plasma tweeters. All of the reviewers at RMAF last year raved about these speakers, and this amp will work very nice. Ask Roger about these speakers, he has heard them.

http://www.vaughnloudspeakers.com/Speakers.php

I'm sure it's very nice, but the Triode gets real pricey with that plasma tweeter.

Alternatively, get the older version Triode with ribbon tweeter.  I have a pair and they are superb with every amp I throw at them, including low power SET.

Call Jim, he is running specials on some Zinfandel models --  basically a small Triode --  and a smaller Triode prototype.

See info here:

http://vaughnloudspeakers.com/Specials.php
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: OzarkTom on 22 Jun 2014, 09:36 pm
I'm sure it's very nice, but the Triode gets real pricey with that plasma tweeter.

Alternatively, get the older version Triode with ribbon tweeter.  I have a pair and they are superb with every amp I throw at them, including low power SET.

Call Jim, he is running specials on some Zinfandel models --  basically a small Triode --  and a smaller Triode prototype.

See info here:

http://vaughnloudspeakers.com/Specials.php

$5K for Triode Jrs. plus plasma tweeters, that is a steal. Nothing beats plasma tweeters. :D
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 23 Jun 2014, 02:47 am
Those plasma tweeters look great!


$5K for Triode Jrs. plus plasma tweeters, that is a steal. Nothing beats plasma tweeters. :D
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 23 Jun 2014, 02:50 am
Thanks Lin,


Sometimes a piece of gear gets into you and you have to jump.


I'm excited.


http://www.audiocircle.com/index.php?topic=120165.0 (http://www.audiocircle.com/index.php?topic=120165.0)



When I had a RM10 many speakers paired well (even the 85 dB SP-BS22-LR), so I would say anything around 87dB and up.

I have bought an amp first and then searched for speakers several times, a lot of fun me thinks.  :green:

Lin
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 23 Jun 2014, 02:54 am
I've been looking at Quads but don't know enough about them not having experienced them. I have a few others in mind and will ask for opinions as the time gets closer.


Obviously your budget or listening tastes are going to play into this but I use the Audiokinesis Jazz Modules (original with TAD drivers). Furthermore, even though the speakers have a minimum 8 ohm load and pretty much operate in the near 10 ohm range I use the 4 ohm tap on the RM-10. Roger referees to this as light loading and it certainly beneficial in my experience. I am also looking for a nice set of Quad ESL-57s for this amp. IIRC Roger built the RM-10 for use with his own ESL-57s.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: James Romeyn on 23 Jun 2014, 04:07 am
This is a shameless plug, but it's also a direct reply to Q posted in the OP.  Mod please delete as desired.

Since discovering the joys of speakers with sensitivity in the low-mid 90 dB range, it's my distinct opinion that systems with the highest value require no more than about 20-30 tube watts to play live music levels with uncompressed peaks.  This being the case, there's absolutely nothing wrong with starting out with the amp and then considering speakers later. 

I know AudioKinesis Zephrin 46 (http://www.audiocircle.com/index.php?topic=125924.new;topicseen#new) plays live SPL with as little as 10-12 tube watts, because we displayed it with such amp a few weeks ago at Newport THE Show.  Each channel/each enclosure of Zephrin 46 comprises two discreet speaker systems, each flat 16 Ohm above the bass range/12 Ohm minimum, with easy phase angles.  The two 16 Ohm sections wire either parallel for 8 Ohm or series for 32 Ohm (think OTL amps, whose power increases with rising impedance). 

As a matter of fact, in shopping for a tube amp for use in my studio to power Zephrin 46 and Dream Maker LCS, the lovely RM-10 Mk II nears the top of my short list.

$4900/pr including shipping MSRP Zephrin 46 falls one-half to one step behind the world's best electrostatic panels in pure detail and transparency.  It's also behind it's bigger twice as costly Dream Maker LCS (http://jamesromeyn.com/#/home-audio-gear/dream-maker-lcs-late-ceiling-splash-loudspeaker-system) brother in this respect.  In every other parameter it excels, especially neutrality and spatial effects.  One of it's most attractive features is wide array of user tuning features for spectral balance, room acoustics, and partnering components.  The cherry on top is a unique, proprietary, electro-mechanical bass mode damping feature that functions in 3-dimensional space as opposed to line level EQ that worsens performance outside microphone test locations.

Zephrin 46 made TAS/Dr. Robert E. Greene's list of Top Five Speakers <$15k/pr at Newport THE Show.  I have special pricing on both models for show demos in walnut.  It may seem strange, but I think it's a reasonable proposition to ship one speaker, audition it in mono, and if it meets performance expectations, ship the other speaker.  If not, return in like condition and buyer looses only return shipping.  I wish I could remember the names, but over the years I've heard that some designers fine tune one speaker by itself before final tests in stereo.         
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 23 Jun 2014, 04:32 am
I recommend QUAD 57s with my subwoofer system. Thats what I listen to when I am not listening to my ESLs. I have had 2 sets in here recently to fix up for customers. FYI I do QUAD repairs and exotic amps. Just had a  rare Dynavector DV 8250 and DV 3000 Gold preamp through here.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 23 Jun 2014, 06:13 am

Thank you Roger!





I recommend QUAD 57s with my subwoofer system. Thats what I listen to when I am not listening to my ESLs. I have had 2 sets in here recently to fix up for customers. FYI I do QUAD repairs and exotic amps. Just had a  rare Dynavector DV 8250 and DV 3000 Gold preamp through here.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 23 Jun 2014, 06:14 am

James,


Thank you for opening my eyes AND ears to these. I will seriously check them out.



This is a shameless plug, but it's also a direct reply to Q posted in the OP.  Mod please delete as desired.

Since discovering the joys of speakers with sensitivity in the low-mid 90 dB range, it's my distinct opinion that systems with the highest value require no more than about 20-30 tube watts to play live music levels with uncompressed peaks.  This being the case, there's absolutely nothing wrong with starting out with the amp and then considering speakers later. 

I know AudioKinesis Zephrin 46 (http://www.audiocircle.com/index.php?topic=125924.new;topicseen#new) plays live SPL with as little as 10-12 tube watts, because we displayed it with such amp a few weeks ago at Newport THE Show.  Each channel/each enclosure of Zephrin 46 comprises two discreet speaker systems, each flat 16 Ohm above the bass range/12 Ohm minimum, with easy phase angles.  The two 16 Ohm sections wire either parallel for 8 Ohm or series for 32 Ohm (think OTL amps, whose power increases with rising impedance). 

As a matter of fact, in shopping for a tube amp for use in my studio to power Zephrin 46 and Dream Maker LCS, the lovely RM-10 Mk II nears the top of my short list.

$4900/pr including shipping MSRP Zephrin 46 falls one-half to one step behind the world's best electrostatic panels in pure detail and transparency.  It's also behind it's bigger twice as costly Dream Maker LCS (http://jamesromeyn.com/#/home-audio-gear/dream-maker-lcs-late-ceiling-splash-loudspeaker-system) brother in this respect.  In every other parameter it excels, especially neutrality and spatial effects.  One of it's most attractive features is wide array of user tuning features for spectral balance, room acoustics, and partnering components.  The cherry on top is a unique, proprietary, electro-mechanical bass mode damping feature that functions in 3-dimensional space as opposed to line level EQ that worsens performance outside microphone test locations.

Zephrin 46 made TAS/Dr. Robert E. Greene's list of Top Five Speakers <$15k/pr at Newport THE Show.  I have special pricing on both models for show demos in walnut.  It may seem strange, but I think it's a reasonable proposition to ship one speaker, audition it in mono, and if it meets performance expectations, ship the other speaker.  If not, return in like condition and buyer looses only return shipping.  I wish I could remember the names, but over the years I've heard that some designers fine tune one speaker by itself before final tests in stereo.       
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 23 Jun 2014, 06:04 pm
This is a shameless plug, but it's also a direct reply to Q posted in the OP.  Mod please delete as desired.

Since discovering the joys of speakers with sensitivity in the low-mid 90 dB range, it's my distinct opinion that systems with the highest value require no more than about 20-30 tube watts to play live music levels with uncompressed peaks.  This being the case, there's absolutely nothing wrong with starting out with the amp and then considering speakers later. 

I know AudioKinesis Zephrin 46 (http://www.audiocircle.com/index.php?topic=125924.new;topicseen#new) plays live SPL with as little as 10-12 tube watts, because we displayed it with such amp a few weeks ago at Newport THE Show.  Each channel/each enclosure of Zephrin 46 comprises two discreet speaker systems, each flat 16 Ohm above the bass range/12 Ohm minimum, with easy phase angles.  The two 16 Ohm sections wire either parallel for 8 Ohm or series for 32 Ohm (think OTL amps, whose power increases with rising impedance). 

As a matter of fact, in shopping for a tube amp for use in my studio to power Zephrin 46 and Dream Maker LCS, the lovely RM-10 Mk II nears the top of my short list.

$4900/pr including shipping MSRP Zephrin 46 falls one-half to one step behind the world's best electrostatic panels in pure detail and transparency.  It's also behind it's bigger twice as costly Dream Maker LCS (http://jamesromeyn.com/#/home-audio-gear/dream-maker-lcs-late-ceiling-splash-loudspeaker-system) brother in this respect.  In every other parameter it excels, especially neutrality and spatial effects.  One of it's most attractive features is wide array of user tuning features for spectral balance, room acoustics, and partnering components.  The cherry on top is a unique, proprietary, electro-mechanical bass mode damping feature that functions in 3-dimensional space as opposed to line level EQ that worsens performance outside microphone test locations.

Zephrin 46 made TAS/Dr. Robert E. Greene's list of Top Five Speakers <$15k/pr at Newport THE Show.  I have special pricing on both models for show demos in walnut.  It may seem strange, but I think it's a reasonable proposition to ship one speaker, audition it in mono, and if it meets performance expectations, ship the other speaker.  If not, return in like condition and buyer looses only return shipping.  I wish I could remember the names, but over the years I've heard that some designers fine tune one speaker by itself before final tests in stereo.       

I did look at the speaker. Its nice that it is available in 32 ohms, so thanks for that. Personally, I'm not inclined to compare cones to ESLs.

I have heard some speakers that rival ESLs in midrange clarity (the inexpensive Pioneer SP-bs22 is excellent at $130 a pair). It was a bit of an inspiration for the OTL-1. In visiting a friend who had stacked them 4 high I got to thinking, here is a 32 ohm load if connected in series. One pair is fine for nearfield use, but a stack of 4 made a nice linesource, more bass, though I think a sub is still warranted. A line source is my preferred type of speaker as solves many acoustic problems like floor bounce, vertical directionality and I think makes the most sensible choice in how to, as Beveridge said, "illuminate a room". Overall this attractive stack was the best $500 speaker I have ever heard.  There are several reviews of this speaker, Stereophile being one of them. http://www.stereophile.com/content/pioneer-sp-bs22-lr-loudspeaker

The OTL-1 would be very happy driving this load to very high levels. Stacking them higher is fine too. At 86 dB sensitivity they are a bit low but a stack of 4 will raise the efficiency 6 dB to 92 and there will be far less drop-off with distance. We know a line source drops off more gradually than a point source. I believe the numbers are 6 dB vs 3 dB when you double the distance. So if you listen several meters from your speaker that will be an important factor in choosing the line source.

As the speaker impedance is increased we get more amplifier power also. In total the system power will rise 6 dB every time we double the number of speakers. That 3 dB from the speaker and 3 dB from the amplifier for each doubling.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: James Romeyn on 23 Jun 2014, 10:52 pm
Well engineered electrostatic panel exceeds the best cone in speed, providing great detail and transparency.  The longer one has enjoyed the audiophile pursuit, the more likely they know that a wide array of performance attributes contribute to overall sense of joy and pleasure.  And each individual weighs those performance attributes differently.  We all know what we like and how much we like it when we hear it.       

Late Ceiling Splash (LCS) provides a unique radiation pattern meeting all of Dr. Floyd Toole's and Dr. Earl Geddes' four specifications for ideal reverberant field.  At least one unnamed specification exceeds any other architecture including electrostatic panel.

Jason Victor Serinus of Stereophile noted HERE (http://www.stereophile.com/content/show-2014-day-2-afternoon#comment-538946):

Quote
...The way the speakers' LCS Late Ceiling Splash radiation pattern, which was invented by James Romeyn and Duke LeJeune (implementing reverberant field theories by Dr. Floyd Toole and Dr. Earl Geddes), threw images way high, as well as their amazing three-dimensionality, was quite impressive...

Toole specifies an ideal reverberant field provides the ear-brain a so-called "second look" at the original waveform, increasing the listener's sensitivity to pitch and detail information.  For instance: the on-axis signal portrays an F# fundamental tone.  A "second look" in the reverberant field confirms and cements the initial on-axis perception.  This happens in real time, and rather than distract the listener, it decreases stress and allows the listener to more fully relax into the illusion of live sound.

After working with LCS for a few years now, I feel safe in reporting that it increases detail and pitch sensitivity.  In fact, I believe it increases pitch sensitivity so well that one interesting result is the listener's ability to appreciate more complex musical scores, and increased interest in music which previously the did not interest the listener. 

I'm under the impression that cone/dome speaker builders constantly struggle with yin-yang regarding detail vs. musicality or smooth musical presentation.  There's a certain preferred middle point on this imaginary scale.  Too much detail decreases musical enjoyment and causes fatigue.  Too much musical smoothness masks detail. 

LCS generates detail and transparency in a unique and efficient fashion that decreases fatigue and increases listening satisfaction and musicality.  LCS does not rely on the usual detail vs. musicality scale described earlier. 

Reflected energy arriving prior to about 10ms does not help in the way described above because the ear-brain can not properly separate and process it compared to the initial on-axis signal.  Speed of sound 1130fps x .01s (10ms) = 11.3ft.  Dipole and bipole lovers often prefer about 5.5ft front wall spacing because 5.5' approaches a 10ms delayed reverberant field (speaker to wall back to speaker).       

Dipole, Bipole, and omni-pole rely on front wall reflection for reverberant field effects, while LCS does not.  LCS can setup flush with the front wall and still maintain most of its spatial excellence including the "second look" mentioned above (stage depth increases with some front wall spacing).

LCS also provides electro-mechanical bass mode damping feature throughout most of the listening room, not like EQ which worsens performance outside the mic test locations. 

One last item, and my apology for being so long winded.  With all the legendary accolades heaped on Peter Walker's Quad 57, home theater use is not one of them.  After spending significant time assembling the highest value and best performing 2-ch music system, why must one suffer inferior audio performance in the HT system?  Especially going from one of Roger's tube amps to a digital amp receiver!  Yech!

Down to its high 30 Hz cutoff, two Zephrin 46 provide a superb L/R Front Array for HT, including uncompressed peaks with low powered tube amp.   

The great tube fanatic Lynn Olson says dedicated HT speakers generally have extremely "dry" acoustic in the front LCR array, providing ambiance and reverberant field effects only in the surrounds.  Lynn says this is the opposite of nature, causing quick fatigue and desire to do something else. 

Conversely, Zephrin 46s LCS provide dense and immersive spatial effects in the L/R Front Array.  Lastly, its center image quality from only two L/R speakers challenges the most costly L/C/R array. 

And no dreaded step down in performance when moving from 2-ch to HT.  Build two to four mono pole speakers (no other radiation pattern) into the walls and you're done...(well, maybe a sub too).                 
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Clio09 on 24 Jun 2014, 04:05 am
Hi Roger,

Thanks for mentioning the Pioneer speakers. I had an opportunity to sit with Andrew Jones for an extended period of time at CES along with several folks and he was gushing over his new Pioneer designs. Your comment on the stacked pairs really has me intrigued and I will be trying this out in the near future.

I would also like to note that it was my room at Newport where we had the Zephrin 46 speakers paired with Our 300b amps and a set of Atma-Sphere m-60s. While being able to run those speakers as a 32 ohm load is certainly an attraction, I will say that both amps performed better with the 8 ohm configuration.

I did look at the speaker. Its nice that it is available in 32 ohms, so thanks for that. Personally, I'm not inclined to compare cones to ESLs.

I have heard some speakers that rival ESLs in midrange clarity (the inexpensive Pioneer SP-bs22 is excellent at $130 a pair). It was a bit of an inspiration for the OTL-1. In visiting a friend who had stacked them 4 high I got to thinking, here is a 32 ohm load if connected in series. One pair is fine for nearfield use, but a stack of 4 made a nice linesource, more bass, though I think a sub is still warranted. A line source is my preferred type of speaker as solves many acoustic problems like floor bounce, vertical directionality and I think makes the most sensible choice in how to, as Beveridge said, "illuminate a room". Overall this attractive stack was the best $500 speaker I have ever heard.  There are several reviews of this speaker, Stereophile being one of them. http://www.stereophile.com/content/pioneer-sp-bs22-lr-loudspeaker

The OTL-1 would be very happy driving this load to very high levels. Stacking them higher is fine too. At 86 dB sensitivity they are a bit low but a stack of 4 will raise the efficiency 6 dB to 92 and there will be far less drop-off with distance. We know a line source drops off more gradually than a point source. I believe the numbers are 6 dB vs 3 dB when you double the distance. So if you listen several meters from your speaker that will be an important factor in choosing the line source.

As the speaker impedance is increased we get more amplifier power also. In total the system power will rise 6 dB every time we double the number of speakers. That 3 dB from the speaker and 3 dB from the amplifier for each doubling.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tubegroove on 24 Jun 2014, 12:56 pm
FWIW, if you are interested in regular cone speakers check out Green Mountain Audio bookshelf speakers (EOS or Rio depending on your budget).  These are honest 90dB and benign 4ohm impedance (www.greenmountainaudio.com).  Very real and musical, first order x-over speakers which work well with the RM10MkII (35w version).  Also look for them cheaper on the used market
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: corndog71 on 24 Jun 2014, 03:31 pm
I can recommend some high quality b-stock speakers.  They just need a little more poly-fill inside the cabinets.

http://www.audiocircle.com/index.php?topic=116702.0
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: tdinut on 1 Jul 2014, 12:51 am
Any opinion on using Devore 0/96 with the RM-10? A friend has a pair for sale. I can't try them, he's in another state.


Description: Two-way, stand-mounted loudspeaker with reflex port. Drive-units: 1" silk-dome tweeter, 10" paper-cone woofer. Frequency range: 25Hz–28kHz. Sensitivity: 96dB/W/m. Impedance: 10 ohms nominal, 8.75 ohms minimum (at 200Hz).

[size=78%](http://www.audiocircle.com/image.php?id=101784)[/size]

[/size]http://www.devorefidelity.com/speakers/images/o96.jpg (http://www.devorefidelity.com/speakers/images/o96.jpg)[size=78%][/color]
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: JackD on 1 Jul 2014, 03:58 am
Joe

Those should work great with the RM-10.  Most of the time those are driven with SET's of lower output than the RM-10. I have driven 2CE Sigs with the RM-10 in the past to much higher levels than you usually listen to.  Also as tubegroove said, the Green Mountains work well too.  The RM-10 is in my office now with the Green Mountain Europa.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: corndog71 on 1 Jul 2014, 06:12 pm
Oooh!  The Orangutans!  I heard those at Axpona and was very impressed.  They sounded way better than one might think coming from such a generic-looking box enclosure.  Not too crazy-priced either if I remember correctly.  The finish on them was excellent.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: bdp24 on 5 Jul 2014, 06:26 pm
I did look at the speaker. Its nice that it is available in 32 ohms, so thanks for that. Personally, I'm not inclined to compare cones to ESLs.

I have heard some speakers that rival ESLs in midrange clarity (the inexpensive Pioneer SP-bs22 is excellent at $130 a pair). It was a bit of an inspiration for the OTL-1. In visiting a friend who had stacked them 4 high I got to thinking, here is a 32 ohm load if connected in series. One pair is fine for nearfield use, but a stack of 4 made a nice linesource, more bass, though I think a sub is still warranted. A line source is my preferred type of speaker as solves many acoustic problems like floor bounce, vertical directionality and I think makes the most sensible choice in how to, as Beveridge said, "illuminate a room". Overall this attractive stack was the best $500 speaker I have ever heard.  There are several reviews of this speaker, Stereophile being one of them. http://www.stereophile.com/content/pioneer-sp-bs22-lr-loudspeaker

The OTL-1 would be very happy driving this load to very high levels. Stacking them higher is fine too. At 86 dB sensitivity they are a bit low but a stack of 4 will raise the efficiency 6 dB to 92 and there will be far less drop-off with distance. We know a line source drops off more gradually than a point source. I believe the numbers are 6 dB vs 3 dB when you double the distance. So if you listen several meters from your speaker that will be an important factor in choosing the line source.

As the speaker impedance is increased we get more amplifier power also. In total the system power will rise 6 dB every time we double the number of speakers. That 3 dB from the speaker and 3 dB from the amplifier for each doubling.

Roger, when the Pioneers are stacked, aren't the acoustic centers of the tweeters far enough apart to cause audible comb-filtering over much of the driver's bandpass? Even slight head movement will result in pretty severe phase-cancellation, I would think.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 6 Jul 2014, 09:00 pm
Roger, when the Pioneers are stacked, aren't the acoustic centers of the tweeters far enough apart to cause audible comb-filtering over much of the driver's bandpass? Even slight head movement will result in pretty severe phase-cancellation, I would think.

Perhaps, but I thought they sounded pretty good. I only listened to the stack briefly. I did buy a pair and listen to them with my sub and was very pleased by the accuracy of the midrange and highs.

I hear a lot about this comb-filtering effect. I design and work with line source Electrostatic Speakers which do not have that problem.  Perhaps you can send a link to a good paper. I am not so sure it is a big deal, but I will comment. The filtering would be up and down and not side to side I believe. I don't move up and down when I listen.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Doublej on 6 Jul 2014, 10:17 pm
Roger

Where can one find information on your subs?
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 7 Jul 2014, 02:48 am
There is a bit here  http://www.audiocircle.com/index.php?topic=45966.0

You can write airhead, he has a pair with his Stax ESLs and loves them.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: corndog71 on 7 Jul 2014, 04:00 am
Roger, when the Pioneers are stacked, aren't the acoustic centers of the tweeters far enough apart to cause audible comb-filtering over much of the driver's bandpass? Even slight head movement will result in pretty severe phase-cancellation, I would think.

According to one speaker designer, you would be better off turning one of the stacked speakers around to face the front wall.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 7 Jul 2014, 05:02 am
According to one speaker designer, you would be better off turning one of the stacked speakers around to face the front wall.

That sounds fine to me. I would choose one not at ear level nor at the bottom.

Here is a good article on comb filtering. Note that often he is talking about multiple drivers horizontally not vertically.  http://www.audioholics.com/loudspeaker-design/comb-filtering

It  might be interesting to rotate the speakers slightly to spread the highs as Sonab did with their tweeters.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: bdp24 on 8 Jul 2014, 05:33 am
According to one speaker designer, you would be better off turning one of the stacked speakers around to face the front wall.

Just the guy I was going to refer Roger to, Corndoggie (I recognize you from our mutual interest, Danny Richie's speaker design work). Danny Richie at GR Research talks about the subject quite a lot. I use panels exclusively (except as subs. I even use the bass panels of Tympani IV's as woofer panels!), so it's not a major concern of mine. Cones have bigger problems than possible comb-filtering!
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Flyin_V on 20 Jul 2014, 06:27 am
In visiting a friend who had stacked them 4 high I got to thinking, here is a 32 ohm load if connected in series. One pair is fine for nearfield use, but a stack of 4 made a nice linesource, more bass, though I think a sub is still warranted. Overall this attractive stack was the best $500 speaker I have ever heard.  There are several reviews of this speaker, Stereophile being one of them. http://www.stereophile.com/content/pioneer-sp-bs22-lr-loudspeaker.

Roger,

The stacking sounds very interesting. Were all four boxes placed with the woofers on the bottom or were the second and forth pair inverted?

Now if the 22s will go on sale again for $65.  :D

Thanks.

Lary
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 20 Jul 2014, 06:47 pm
When were they on sale for $65? What a deal. Are they overstocked? I did walk into Good Guys or one like it and was told they had them but no more.

I don't think the stacking position would make much difference, but one could put on long enough wires and play with it.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: OzarkTom on 20 Jul 2014, 07:06 pm
srb said New Egg has them today for $80 shipped.
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: dburna on 20 Jul 2014, 07:09 pm
Any opinion on using Devore 0/96 with the RM-10? A friend has a pair for sale. I can't try them, he's in another state.


Description: Two-way, stand-mounted loudspeaker with reflex port. Drive-units: 1" silk-dome tweeter, 10" paper-cone woofer. Frequency range: 25Hz–28kHz. Sensitivity: 96dB/W/m. Impedance: 10 ohms nominal, 8.75 ohms minimum (at 200Hz).

[size=78%](http://www.audiocircle.com/image.php?id=101784)[/size]

[/size]http://www.devorefidelity.com/speakers/images/o96.jpg (http://www.devorefidelity.com/speakers/images/o96.jpg)[size=78%][/color]

I listened to these at AXPONA 2014 (Chicago) under sub-optimal conditions, and these were one of the (very) few speakers that I liked.  I have been less enthusiastic about some of the other DeVore speakers (thought some of them were a little bland), so take this assessment for what it is worth.  I thought the O/96's had an immediacy that some of the other DeVore's lacked.

Regards, -dB
Title: Re: Speaker Recommendations for the RM-10 MK II 25 watt version ....
Post by: Roger A. Modjeski on 20 Jul 2014, 09:24 pm
I listened to these at AXPONA 2014 (Chicago) under sub-optimal conditions, and these were one of the (very) few speakers that I liked.  I have been less enthusiastic about some of the other DeVore speakers (thought some of them were a little bland), so take this assessment for what it is worth.  I thought the O/96's had an immediacy that some of the other DeVore's lacked.

Regards, -dB

With that sensitivity and highish impedance its a nice speaker for the RM-10 or the new OTL-1.