ER Audio 505 ESL Array/Altec 416 midwoofer/Rythmik sub
I would really appreciate some timely feedback to risk proceeding with my little ESL fantasy, albeit via the back door.
As I have insufficient knowledge (and especially the time) to do much DIYing, Jim Salk Salk Sound is cloning Gary Dahl’s BTA speakers for me (minus the RAAL ribbons, which Gary no longer uses since he switched from his Lundahl transformer coupled 300B p-p amps to Gary Pimm’s vastly upgraded Tabor solid-state amp) http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-1295.html
Jim should have them finished around February. But before he ships them I thought about how the ER Audio 505 panels would work above each GPA Altec416-8B midwoofer. Mini Panels
I’m certainly no expert, but by using two or three 505 panels above each 416 midwoofer, would not soundstage for the highs and upper mids greatly improve in all three dimensions?
As for the critical midrange, Gary passively crosses the (equalized) Azurahorn/Radian driver combo with the Altecs to have the latter begin playing at 700Hz.
The GPA Altec 416’s under hung voice coil keeps distortion low. And Gary has each midwoofer in sealed low diffraction cabinets, where the response goes down to only 70Hz, further minimizing distortion. A pair of Jim’s version of the Rythmik 12" sealed servo subs take over below this.
Whether I use Rob’s passive crossover or bi-amp the system with something like this http://www.firstwatt.com/pdf/prod_b4_man.pdf , would you expect the results to be comparable to those here? https://drive.google.com/file/d/0B1XTT_kQmJ_QNE1wbnVFdUsyLWs/view Note, however, the “milliwatt” typo in the specs.
http://www.jblpro.com/pub/obsolete/4331a_4333a.pdf
At least some things have changed for the better. I am no longer limited to using the First Watt F4 amp, at least not alone. My room size will be either 12 ft x 15 or 14 ft x19, where, due to heat and clutter issues, I would either passively or actively cross the speakers, respectively.
As for bi-amping, I would drive the ~ 97db Altecs with either the F4 or my First Watt J2 (also 25 wpc/ 8 ohms), or sell off one for a really superb sounding Class AB amp.
But if bi-amping, and to drive the ESLs alone, how well would 300B SET monos work?
While they are noted for an awesome 3D soundstage and a magical midrange, don’t their highs roll off soon after 10kHz?
And as they are typically 9 wpc, how much output will they do at 10kHz, when each 505 panel’s impedance drops to 4 ohms? And down to 2 ohms at 20kHz, according to the curve here? Mini Panels
However, in terms of wpc vs. required SPLs, since my average listening levels would be ~ 60db at 1kHz, in a 14 ft x 19 room, at 200Hz they would be only ~73db, as per the 2003 curve https://en.wikipedia.org/wiki/Equal-loudness_contour
On the other hand, as caps in parallel are additive, wouldn’t impedance below 10kHz be approaching zero if I use 3 panels per side? How would the 300B’s output transformers handle that kind of load?
Otherwise, I’d hate giving up on 300B SET magic, but would an OLT tube amp be a much better choice to drive three of those 505 panels? Maybe something like this? ZOTL10 ? Linear Tube Audio
Ultimately, however, as you are the guys with the heavy ESL design, building and in-use experience, please evaluate the feasibility of this particular hybrid speaker + subwoofers concept. If the consensus here does not total 80% or better likelihood for a really awesome sounding build, then there’s no point to risk spending the 505 mini panels, since I don’t think that ER Audio does refunds.
I’d probably go for a passively or actively crossed OB speaker project.
Looking forward to all of your replies.
I would really appreciate some timely feedback to risk proceeding with my little ESL fantasy, albeit via the back door.
As I have insufficient knowledge (and especially the time) to do much DIYing, Jim Salk Salk Sound is cloning Gary Dahl’s BTA speakers for me (minus the RAAL ribbons, which Gary no longer uses since he switched from his Lundahl transformer coupled 300B p-p amps to Gary Pimm’s vastly upgraded Tabor solid-state amp) http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-1295.html
Jim should have them finished around February. But before he ships them I thought about how the ER Audio 505 panels would work above each GPA Altec416-8B midwoofer. Mini Panels
I’m certainly no expert, but by using two or three 505 panels above each 416 midwoofer, would not soundstage for the highs and upper mids greatly improve in all three dimensions?
As for the critical midrange, Gary passively crosses the (equalized) Azurahorn/Radian driver combo with the Altecs to have the latter begin playing at 700Hz.
The GPA Altec 416’s under hung voice coil keeps distortion low. And Gary has each midwoofer in sealed low diffraction cabinets, where the response goes down to only 70Hz, further minimizing distortion. A pair of Jim’s version of the Rythmik 12" sealed servo subs take over below this.
Whether I use Rob’s passive crossover or bi-amp the system with something like this http://www.firstwatt.com/pdf/prod_b4_man.pdf , would you expect the results to be comparable to those here? https://drive.google.com/file/d/0B1XTT_kQmJ_QNE1wbnVFdUsyLWs/view Note, however, the “milliwatt” typo in the specs.
http://www.jblpro.com/pub/obsolete/4331a_4333a.pdf
At least some things have changed for the better. I am no longer limited to using the First Watt F4 amp, at least not alone. My room size will be either 12 ft x 15 or 14 ft x19, where, due to heat and clutter issues, I would either passively or actively cross the speakers, respectively.
As for bi-amping, I would drive the ~ 97db Altecs with either the F4 or my First Watt J2 (also 25 wpc/ 8 ohms), or sell off one for a really superb sounding Class AB amp.
But if bi-amping, and to drive the ESLs alone, how well would 300B SET monos work?
While they are noted for an awesome 3D soundstage and a magical midrange, don’t their highs roll off soon after 10kHz?
And as they are typically 9 wpc, how much output will they do at 10kHz, when each 505 panel’s impedance drops to 4 ohms? And down to 2 ohms at 20kHz, according to the curve here? Mini Panels
However, in terms of wpc vs. required SPLs, since my average listening levels would be ~ 60db at 1kHz, in a 14 ft x 19 room, at 200Hz they would be only ~73db, as per the 2003 curve https://en.wikipedia.org/wiki/Equal-loudness_contour
On the other hand, as caps in parallel are additive, wouldn’t impedance below 10kHz be approaching zero if I use 3 panels per side? How would the 300B’s output transformers handle that kind of load?
Otherwise, I’d hate giving up on 300B SET magic, but would an OLT tube amp be a much better choice to drive three of those 505 panels? Maybe something like this? ZOTL10 ? Linear Tube Audio
Ultimately, however, as you are the guys with the heavy ESL design, building and in-use experience, please evaluate the feasibility of this particular hybrid speaker + subwoofers concept. If the consensus here does not total 80% or better likelihood for a really awesome sounding build, then there’s no point to risk spending the 505 mini panels, since I don’t think that ER Audio does refunds.
I’d probably go for a passively or actively crossed OB speaker project.
Looking forward to all of your replies.
ESL panels are coupled to amplifiers, which transform the low voltage high current of the amplifier to high voltage low current needed by the panel. These transformers define if the Amplifier needs to drive a low impedance or high impedance source.
Modern segmented or, delay line speakers lie say the Quad ESL 63 and its children, and many DIY panels here can have quiet flat impedance over frequency where as simple panels will have impedance drop as frequency increases (like Quad ESL57).
If you dont need bass, then ESL panels can have smaller gaps between the stators and the membrane. This allows them to be more efficient, and hence more suitable for low power amplifiers.
Hence a Quad ESL 57 can be adequately driven with a 10W amp, though I would suggest 30W is what you really want. I believe some of the USA electrostatic speakers want Amplifiers in the 200's W range.
It is quiet possible to make an ESL tweeter that would suffer from being over driven with a 9 W SET as you describe.
Personally I like Class A solid state amps, but dont like electricity bills, so a Class AB amplifier that is mostly in Class A (say up to 5 W) but can deliver 50W is what I would recommend for a Quad ESL 63, but at the moment, i just use Quad 306 amps even if they dont sound as nice as my DIY JLH 15W amplifier, or my Sugden A28's, they have the advantage of being easy to actively crossover, and do not dont eat bucket loads of electricity for breakfast, lunch and dinner.
Modern segmented or, delay line speakers lie say the Quad ESL 63 and its children, and many DIY panels here can have quiet flat impedance over frequency where as simple panels will have impedance drop as frequency increases (like Quad ESL57).
If you dont need bass, then ESL panels can have smaller gaps between the stators and the membrane. This allows them to be more efficient, and hence more suitable for low power amplifiers.
Hence a Quad ESL 57 can be adequately driven with a 10W amp, though I would suggest 30W is what you really want. I believe some of the USA electrostatic speakers want Amplifiers in the 200's W range.
It is quiet possible to make an ESL tweeter that would suffer from being over driven with a 9 W SET as you describe.
Personally I like Class A solid state amps, but dont like electricity bills, so a Class AB amplifier that is mostly in Class A (say up to 5 W) but can deliver 50W is what I would recommend for a Quad ESL 63, but at the moment, i just use Quad 306 amps even if they dont sound as nice as my DIY JLH 15W amplifier, or my Sugden A28's, they have the advantage of being easy to actively crossover, and do not dont eat bucket loads of electricity for breakfast, lunch and dinner.
I have just tried an icepower 700asc2 with my kings electrostatic and it emits regular loud cracking sounds. No music gets through. Works fine with cones. I'm not too impressed withe the sound but it is OK.
When i get the ER audio III going I will give it a try. Otherwise its sub duty only.
Any experience with these?
Regards,
Kffern
Hi,
I´ve yet to come across a class-D amp that sounds natural with ESLs.
They can exhibit a lot of control and the sound can be impressive with Rock Pop and such stuff.
But put a non-amplified voice on or some classical music and the sound becomes cold and dead.
A nice class AB amp that really sounds well and remains utmost stable and cool running is the LJM 12-2 that You can find on ebay quite cheap.
Compared to those FirstWatters it is more powerful and very energy efficient.
jauu
Calvin
I´ve yet to come across a class-D amp that sounds natural with ESLs.
They can exhibit a lot of control and the sound can be impressive with Rock Pop and such stuff.
But put a non-amplified voice on or some classical music and the sound becomes cold and dead.
A nice class AB amp that really sounds well and remains utmost stable and cool running is the LJM 12-2 that You can find on ebay quite cheap.
Compared to those FirstWatters it is more powerful and very energy efficient.
jauu
Calvin
Wow that seems an excellent value! I assume you have to solder it together, a kit consisting of a boards and parts, or only boards?
Jan
Hi Jan,
You can get non-populated boards as well as fully functional assemblies.
I usually purchase the assembled amps and tweak the modules with caps and change the fixed bias generator with a pot.
The Idle current varies too much with the fixed generator from sample to sample.
Featuring a CFP output stage the idle current values can be set very low ... the amps run very cool and don't require large heatsinks.
The four output transistor are beefy enough to allow for bridging, which makes the amps highly interisting for active speaker applications, as only a single power supply is needed (same supply rail voltages for bass- mids- and highs-amps).
Its also easy to experiment with other compensation schemes than the pre-fitted Miller comp.
Lastly, the layout dimensions (only 50mm height) and positioning of the power transistors allows for easy mounting to cooling fins of a nice slim casing.
jauu
Calvin
You can get non-populated boards as well as fully functional assemblies.
I usually purchase the assembled amps and tweak the modules with caps and change the fixed bias generator with a pot.
The Idle current varies too much with the fixed generator from sample to sample.
Featuring a CFP output stage the idle current values can be set very low ... the amps run very cool and don't require large heatsinks.
The four output transistor are beefy enough to allow for bridging, which makes the amps highly interisting for active speaker applications, as only a single power supply is needed (same supply rail voltages for bass- mids- and highs-amps).
Its also easy to experiment with other compensation schemes than the pre-fitted Miller comp.
Lastly, the layout dimensions (only 50mm height) and positioning of the power transistors allows for easy mounting to cooling fins of a nice slim casing.
jauu
Calvin
Hi Oltos,
I now have 2 pairs of Kings electrostats. I use a minidsp 2x8 kit which is basically their 4 x 10 and run them biamped as well as a x/over. I bump up the lower mids a bit to help the amps.
I would recommend the new 2 x 4 (24/96) over Robs x/over and decide on which amp you want to keep later. Your Pass amps are fine IMHO. Get the minidsp measurement gear and you will quite easily get it the way you want it.
Mini-dsp have been very good. I had a problem with one of the boards and they sent a replacement promptly.
I also used the 2 x 4 with Rob's ESL III and it works great. Heaps better than the Reckhorn amp/xover I used to have.
PM if required.
Regards,
kffern
I now have 2 pairs of Kings electrostats. I use a minidsp 2x8 kit which is basically their 4 x 10 and run them biamped as well as a x/over. I bump up the lower mids a bit to help the amps.
I would recommend the new 2 x 4 (24/96) over Robs x/over and decide on which amp you want to keep later. Your Pass amps are fine IMHO. Get the minidsp measurement gear and you will quite easily get it the way you want it.
Mini-dsp have been very good. I had a problem with one of the boards and they sent a replacement promptly.
I also used the 2 x 4 with Rob's ESL III and it works great. Heaps better than the Reckhorn amp/xover I used to have.
PM if required.
Regards,
kffern
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Hu Tyu,
The bass panels take 5Kv and the treble 3.5Kv. I like them but quality control is a major issue. These are a very early model mind you so not an indictment on current production.
I put all the new panels I had into one pair which has 2 bass panels removed and replaced with a 12" woofer (as used by the original owner). Some of the new panels have wrinkled diaphragms. Also HVPS issues which I have sorted. I had tried them with my TL 8" HiVi subs previously. I think I prefer the TLs but it's really a matter of taste. This pair is biamped with a minidsp 4x10. They are in the main family room and I haven't had enough time to mess about with measurements. The wife and kids are leaving me on my own over Xmas holidays so will play about with them then.
The other pair is as original, still has the x/overs and is used occasionally. Best results with a minidsp 2x4 applying boost to the bass (50 to 200 Hz I think). No sub used. Best to keep anything under 50Hz away from the panels for a longer life I think.
Will update my thread when I have tried fixing the many damaged panels. Sometime in Jan'17.
Regards,
kffern
The bass panels take 5Kv and the treble 3.5Kv. I like them but quality control is a major issue. These are a very early model mind you so not an indictment on current production.
I put all the new panels I had into one pair which has 2 bass panels removed and replaced with a 12" woofer (as used by the original owner). Some of the new panels have wrinkled diaphragms. Also HVPS issues which I have sorted. I had tried them with my TL 8" HiVi subs previously. I think I prefer the TLs but it's really a matter of taste. This pair is biamped with a minidsp 4x10. They are in the main family room and I haven't had enough time to mess about with measurements. The wife and kids are leaving me on my own over Xmas holidays so will play about with them then.
The other pair is as original, still has the x/overs and is used occasionally. Best results with a minidsp 2x4 applying boost to the bass (50 to 200 Hz I think). No sub used. Best to keep anything under 50Hz away from the panels for a longer life I think.
Will update my thread when I have tried fixing the many damaged panels. Sometime in Jan'17.
Regards,
kffern
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