Be they Quads, SoundLabs, Sanders, Martin-Logans, ER Audio, Acoustat,
Beveridge-or, of course, one's own design-can anyone say, on whatever
basis, which ones tend to be the amp of choice to drive full range ESLs:
Class A solid-state or Class AB solid-state?
I'll be happy to disclose my reasons for asking this upon several
postings or pm replies.
Thanks to all in advance!
Beveridge-or, of course, one's own design-can anyone say, on whatever
basis, which ones tend to be the amp of choice to drive full range ESLs:
Class A solid-state or Class AB solid-state?
I'll be happy to disclose my reasons for asking this upon several
postings or pm replies.
Thanks to all in advance!
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Sorry John65b I should have known that, particularly for larger rooms a very well designed Class D could speakers that need pushing like ESLs sound great.
Indeed, Sreten many ss amps, like the Parasound and of probably all of Nelson Pass's X series amps are biased where they are in Class A for maybe 10 wpc and then transition to Class AB. Pass's higher biased XA.5 and new XA.8 series, those amps produce far more sweet-sounding Class A power. The downside, of course, for Class A amps are way more heat and power consumption-something that would surely give our climatologist audiophiles a chronic case of the guilts. But for sensible owners, it's fairly easy to avoid abusing the privilege: Let the Class A beast warm up, amass your playlist in the interim, play your choice tunes for an hour after the amp reaches operating temperature and then power it off-or put it in standby. Plenius amps have a 2 watt power draw in Standby.
Indeed, Sreten many ss amps, like the Parasound and of probably all of Nelson Pass's X series amps are biased where they are in Class A for maybe 10 wpc and then transition to Class AB. Pass's higher biased XA.5 and new XA.8 series, those amps produce far more sweet-sounding Class A power. The downside, of course, for Class A amps are way more heat and power consumption-something that would surely give our climatologist audiophiles a chronic case of the guilts. But for sensible owners, it's fairly easy to avoid abusing the privilege: Let the Class A beast warm up, amass your playlist in the interim, play your choice tunes for an hour after the amp reaches operating temperature and then power it off-or put it in standby. Plenius amps have a 2 watt power draw in Standby.
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Acoustat.Xs Servo tube amps...in the 80s....
Acoustat 121 interfaces... Threshold S/500..s300..JaDis Defy7 ....Krell KST 100 a/b...KSA..150 .250 ...Pass ClassA Diy AMps....Hot..
Soundlab A1s....tried to drive Krell KSA150....give up on the Soundlabs..
Never went back....
ML SL3s Ascents Prodigy....Krell...KSA 150 Atma-Sphere M-60...Diy MA1s...QSC pro amps work great an sound vary good on ESLs..
Best sounding ESLs for me...Acoustat & Atma-Sphere OTLs.. like you say...Way Too Hot.....after 1hr....room cooking even with A/c running....
Acoustat 121 interfaces... Threshold S/500..s300..JaDis Defy7 ....Krell KST 100 a/b...KSA..150 .250 ...Pass ClassA Diy AMps....Hot..
Soundlab A1s....tried to drive Krell KSA150....give up on the Soundlabs..
Never went back....
ML SL3s Ascents Prodigy....Krell...KSA 150 Atma-Sphere M-60...Diy MA1s...QSC pro amps work great an sound vary good on ESLs..
Best sounding ESLs for me...Acoustat & Atma-Sphere OTLs.. like you say...Way Too Hot.....after 1hr....room cooking even with A/c running....
Thanks guys for chiming in with your gear. Lots of great amps-of all Classes.
It always amazed me how popular the Acoustats were. So many owners and yet the company folded.
Has anyone here actually heard ER Audio's Acorns? If yes, how did you like them? Any dispersion issues? How was the bass response? What amps were driving them? What was the approximate room size?
Same questions about the Quad 988 and 989. But as its the Acorns that are in production, those are what I'm most looking for feedback on.
It always amazed me how popular the Acoustats were. So many owners and yet the company folded.
Has anyone here actually heard ER Audio's Acorns? If yes, how did you like them? Any dispersion issues? How was the bass response? What amps were driving them? What was the approximate room size?
Same questions about the Quad 988 and 989. But as its the Acorns that are in production, those are what I'm most looking for feedback on.
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I haven't seen the Acorns discussed much on here, so I'll bite. I have built/rebuilt Acorns a few times and the results you get depend, rather obviously, on how you build them because they are hardly 'in production' but a kit with a comprehensive build guide.
Heard as ER Audio intended, full-range 4-panel, they are impressive. I compared them directly with Sanders 10c's, which I also have. The Acorns are very fast and detailed especially using 3.5um Mylar. Slightly light in the bass but beautiful mids and highs and dramatic imaging. They are vertically segmented flat panels so, yes, there are some dispersion issues but nothing like as bad as the Sanders 10c. They need a big room, these are huge panels and you need to drive them hard to get the SPL because of the generous D/S distance. Ultimately, I ran out out of bass and rebuilt them with tighter films and an OB sub. I have 8m x 7m.
I only wish I'd discovered this forum and the golden advice you can read here before simply following the ERA build procedure.
If you are serious about building them:
Buy the kit without the stators pre-glued so that you can work them up to a much higher insulation strength (see Jer's posts) and measure/check it
Don't use the ERA film tightening procedure, use the 'inner tube' instead (see Jazzman's).
Use 3.5um film.
If you use the ERA coating (excellent) make sure you can measure the surface resistivity. It needs a little practice.
Consider whether you really want to go full-range but rather build just 2 panels and use a sub.
Factor in the cost of some serious amplification to play to moderate/high levels. I use Usher R1.5 and a Sanders Magtec on the panels - it needs them.
If you are still keen, PM me.
Marty
Heard as ER Audio intended, full-range 4-panel, they are impressive. I compared them directly with Sanders 10c's, which I also have. The Acorns are very fast and detailed especially using 3.5um Mylar. Slightly light in the bass but beautiful mids and highs and dramatic imaging. They are vertically segmented flat panels so, yes, there are some dispersion issues but nothing like as bad as the Sanders 10c. They need a big room, these are huge panels and you need to drive them hard to get the SPL because of the generous D/S distance. Ultimately, I ran out out of bass and rebuilt them with tighter films and an OB sub. I have 8m x 7m.
I only wish I'd discovered this forum and the golden advice you can read here before simply following the ERA build procedure.
If you are serious about building them:
Buy the kit without the stators pre-glued so that you can work them up to a much higher insulation strength (see Jer's posts) and measure/check it
Don't use the ERA film tightening procedure, use the 'inner tube' instead (see Jazzman's).
Use 3.5um film.
If you use the ERA coating (excellent) make sure you can measure the surface resistivity. It needs a little practice.
Consider whether you really want to go full-range but rather build just 2 panels and use a sub.
Factor in the cost of some serious amplification to play to moderate/high levels. I use Usher R1.5 and a Sanders Magtec on the panels - it needs them.
If you are still keen, PM me.
Marty
Acorns: Too big a diy bite for this noob.
Big thanks to kffern for tapping (?) you, Marty, to reply to my great need to get straight about the Acorns,
before ever daring to order that $4K kit. Looks like that would have been a really bad move.
For one thing, my room for them would only be about 12 ft x 13 ft. My amps are First Watt F4 monos that do a little over 80w into 8 ohms, driven by the Burning Amp BBA-3 preamp. I'd use one or two of Jim Salk’s version of Brian Ding’s Rythmik sealed servo subs.
I know that load impedance of ESLs typically drops down very low beyond about 9kHz, due to their capacitive reactance. But I reasoned that as my ears can’t take average SPLs beyond 80db-if even that much-at 11 feet away, at least in a
room that small, that my F4 monos would well up to the task.
However, I was indeed planning on ordering the mostly pre-assembled kit, which includes the finished bias supply, crossovers and glued stators. Then I thought, it would only be simple matter for a carpenter to come in, measure the stators and build wood frames to encase them. But as you advise against pre-glued stators and where insulation strength and resistivity need special measuring and tweaking, I’d now have to judge this kit as too complex for this nooby guy.
This means that full range ESLs-at least those sounding as good as the Acorns-won’t happen for me. Sanders’ current models are very unaffordable. Ditto for Sound Labs’ entry level model. It’s upsetting news, but thanks for this much needed heads up!
Big thanks to kffern for tapping (?) you, Marty, to reply to my great need to get straight about the Acorns,
before ever daring to order that $4K kit. Looks like that would have been a really bad move.
For one thing, my room for them would only be about 12 ft x 13 ft. My amps are First Watt F4 monos that do a little over 80w into 8 ohms, driven by the Burning Amp BBA-3 preamp. I'd use one or two of Jim Salk’s version of Brian Ding’s Rythmik sealed servo subs.
I know that load impedance of ESLs typically drops down very low beyond about 9kHz, due to their capacitive reactance. But I reasoned that as my ears can’t take average SPLs beyond 80db-if even that much-at 11 feet away, at least in a
room that small, that my F4 monos would well up to the task.
However, I was indeed planning on ordering the mostly pre-assembled kit, which includes the finished bias supply, crossovers and glued stators. Then I thought, it would only be simple matter for a carpenter to come in, measure the stators and build wood frames to encase them. But as you advise against pre-glued stators and where insulation strength and resistivity need special measuring and tweaking, I’d now have to judge this kit as too complex for this nooby guy.
This means that full range ESLs-at least those sounding as good as the Acorns-won’t happen for me. Sanders’ current models are very unaffordable. Ditto for Sound Labs’ entry level model. It’s upsetting news, but thanks for this much needed heads up!
ER Audio's ESL Mini Panels?
Marty, as the Acorns are obviously not a safe way to go for me, what about Rob's Mini Panels? Mini Panels ?
I thought about passively crossing them
XM46 Passive Line Level Crossover Network, PLLXO, 24 dB/oct with a pair of GPA's Altec 416-8Bs
http://www.greatplainsaudio.com/downloads/416-8B Spec Sheet.pdf
I could get the 16 ohm Altec 416s, though they are 98db. In Gary Dahl's 3 cu. ft. sealed boxes, their low end is cut off below 70Hz, where my pair of Rythmik active servo sealed subs could take over.
My First Watt F4 amp does 25 wpc/8 ohms; 40 wpc/4 ohms. Do you think this will fly in my small room with my sensitive ears?
Marty, as the Acorns are obviously not a safe way to go for me, what about Rob's Mini Panels? Mini Panels ?
I thought about passively crossing them
XM46 Passive Line Level Crossover Network, PLLXO, 24 dB/oct with a pair of GPA's Altec 416-8Bs
http://www.greatplainsaudio.com/downloads/416-8B Spec Sheet.pdf
I could get the 16 ohm Altec 416s, though they are 98db. In Gary Dahl's 3 cu. ft. sealed boxes, their low end is cut off below 70Hz, where my pair of Rythmik active servo sealed subs could take over.
My First Watt F4 amp does 25 wpc/8 ohms; 40 wpc/4 ohms. Do you think this will fly in my small room with my sensitive ears?
The real question has nothing to do with the class of the amplifier.
If ur into measurements then what sounds best will likely correlate to the ratios in the spectra of distortion. Then that correlates to what you think sounds best.
The only "ringer" question is going to be what about those amps that claim residual distortion levels. Will the spectra matter?
Another part of this equation is that ESLs tend to be reasonably reactive loads - most amps are not measured (at least not the published measurements) into reactive loads. So, trying to know which amps produce what sort of distortion spectra into a real world ESL is going to be something that either you will need to test and discover, or else one has to rely upon reports from others and/or your ears.
The final part of the equation is powah. Most ESLs are not so much wattage eaters, but voltage eaters. In real world amps, higher voltages on the rails = higher power because the voltage *might* be required to match up to a low Z load. That equates more often than not to a big AB amp. Speakers like the Quads of course have a power limit that is low and also an SPL limit to match.
My vote for something like the Quad 57s is a class A amp of some sort, be it tube or solid state (a nice F5 comes to mind! ). For something like an Acoustat, you need raw voltage swing. With a Martin Logan, you need to be able to handle wacky impedance swings, low Z and reactive phase angles...
No single way to go, friends. Like everything else, right tool for the job?
If ur into measurements then what sounds best will likely correlate to the ratios in the spectra of distortion. Then that correlates to what you think sounds best.
The only "ringer" question is going to be what about those amps that claim residual distortion levels. Will the spectra matter?
Another part of this equation is that ESLs tend to be reasonably reactive loads - most amps are not measured (at least not the published measurements) into reactive loads. So, trying to know which amps produce what sort of distortion spectra into a real world ESL is going to be something that either you will need to test and discover, or else one has to rely upon reports from others and/or your ears.
The final part of the equation is powah. Most ESLs are not so much wattage eaters, but voltage eaters. In real world amps, higher voltages on the rails = higher power because the voltage *might* be required to match up to a low Z load. That equates more often than not to a big AB amp. Speakers like the Quads of course have a power limit that is low and also an SPL limit to match.
My vote for something like the Quad 57s is a class A amp of some sort, be it tube or solid state (a nice F5 comes to mind! ). For something like an Acoustat, you need raw voltage swing. With a Martin Logan, you need to be able to handle wacky impedance swings, low Z and reactive phase angles...
No single way to go, friends. Like everything else, right tool for the job?
@oltos
I have no direct experience of Rob's Mini Panels but there is obviously a lot of interest in them because I received couple of PM's about them just this week. For a room your size at moderate volume and at the price, they look very interesting. There's a wealth of knowledge here on small panels - see Gerald, esp. The only issue I'd probably have with them is their 200Hz limitation which makes for a lot of head scratching for the critical lower 3 octaves. I would agree with Rob's preferred bass methods, I use OB subs (Linkwitz) but they will be too big for your room.
I'm no general authority on ESL (which is why I'm on here) but here's my experience:
ER Audio doesn't show an impedance curve and I don't know your amps but on the occasion I have played with lower power PP and SE valve amps and ESL's I had no issues at modest volumes. Maybe I was lucky. Your F4 is claimed to provide 100W into 2 ohms so they are probably stable below that, the characteristic that would worry me is their unity voltage gain. The trafo shown on Rob's site appears to be his custom wound 1:100 which, as bear explains, may not give enough system voltage swing for panels.
The sensitivity is higher than the Acorns which makes them easier to pair with dynamic drivers but there's a lot of music in that bottom end and I would think long & hard and do a lot of simulations & trials before deciding on drivers and housings. I've always found Rob both responsive and extremely helpful - I would ask him.
I gave up long ago trying to integrate drivers with differing sensitivity, FR & phase. I do x-over, measurements & corrections with DEQX so I'm the last person to ask about passive crossovers.
Marty
I have no direct experience of Rob's Mini Panels but there is obviously a lot of interest in them because I received couple of PM's about them just this week. For a room your size at moderate volume and at the price, they look very interesting. There's a wealth of knowledge here on small panels - see Gerald, esp. The only issue I'd probably have with them is their 200Hz limitation which makes for a lot of head scratching for the critical lower 3 octaves. I would agree with Rob's preferred bass methods, I use OB subs (Linkwitz) but they will be too big for your room.
I'm no general authority on ESL (which is why I'm on here) but here's my experience:
ER Audio doesn't show an impedance curve and I don't know your amps but on the occasion I have played with lower power PP and SE valve amps and ESL's I had no issues at modest volumes. Maybe I was lucky. Your F4 is claimed to provide 100W into 2 ohms so they are probably stable below that, the characteristic that would worry me is their unity voltage gain. The trafo shown on Rob's site appears to be his custom wound 1:100 which, as bear explains, may not give enough system voltage swing for panels.
The sensitivity is higher than the Acorns which makes them easier to pair with dynamic drivers but there's a lot of music in that bottom end and I would think long & hard and do a lot of simulations & trials before deciding on drivers and housings. I've always found Rob both responsive and extremely helpful - I would ask him.
I gave up long ago trying to integrate drivers with differing sensitivity, FR & phase. I do x-over, measurements & corrections with DEQX so I'm the last person to ask about passive crossovers.
Marty
What about one per side of these alnico drivers in a sealed box? Tubby 12”
Red Alnico 12" 8 Ohm Altec 414 http://www.greatplainsaudio.com/downloads/414-8B Spec Sheet.pdf and 15” Altec 416 http://www.greatplainsaudio.com/downloads/416-8B Spec Sheet.pdf
They are 96db, 96db and 98db, respectively. I know that the Altec 416 goes
flat to 70Hz and with very low IM distortion. That's where Gary Dahl's 3 cu ft sealed box cuts them off and where his subs take over. I'd use a pair of these subs Rythmik Audio servo subwoofer 12" F12G
The trouble is that the 505 mini panels are only 88db. And as you imply below, matching drivers this many db apart is probably impossible without bi-amping or DSP, both of which I'd prefer to avoid in this case (as my DAC will be pretty high end).
I'm about ready to build Nelson Pass's BA-3
http://www.diyaudio.com/forums/pass-labs/201281-burning-amp-ba-3b-balanced-44.html which delivers at least 15v rms unbalanced/channel.
Sadly, only about a 2db boost, 8db less than two of the thee above drivers that I'd prefer to use (Alnicos are said to offer a superb lower midrange/midbass).
arcysparky;4315024 I gave up long ago trying to integrate drivers with differing sensitivity said:
Hi Bear,
It's my new home. Have only just testing the set up. Acoustic treatment will be added
soon. Right now slowing dialing in the position of the speakers to get the best sound.
Btw it's my bed room lol , the floor reflection isn't that great cause the back wall is about
7 ft away from the listening position
Cheers
It's my new home. Have only just testing the set up. Acoustic treatment will be added
soon. Right now slowing dialing in the position of the speakers to get the best sound.
Btw it's my bed room lol , the floor reflection isn't that great cause the back wall is about
7 ft away from the listening position
Cheers
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