I’m listening right now to a pair of Quad 2805s driven by Mola Mola electronics ( the Makua preamp feeding the Kaluga mono blocs). The Kalugas are Brian Putzey’s class D design originally when he worked for the electronics giant Philips. It might be related to Hypex. They sound very nice indeed, but for my larger 2905s, I much prefer a pair of Audio Research Ref 210 mono blocs. These behemoths produce a creamy midrange that I haven’t found any solid state amp (class D or A/B) capable of producing. Quads have high impedances in the bass (around 60 ohms). Garden variety solid state amps just sound anemic given that impedance. The best I found is a pair of D-Sonic class D amps that produce 1500 watts per channel. These have enough power to make the bass sound fine but their midrange leaves a lot to be desired.
Anyone have Sound Lab electrostatic speakers? I Searched...
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Yes, I know, I have a pair of 3.1 Improveds; the 100-pounders I mentioned are the SS amps in the way. And perhaps after I'm rid of a couple-more pairs of those 100-pounders, I will try the '1's.
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My limited experience with PL amps is that each model has its own unique sonic signature. Don't believe there is a PL "house sound" per se.
My general impression is that Nelson Pass designs tend to a bit on the fast lean side compared to other solid state designers (e.g., Dan Dagastino, or Mark Levinson ) that sound warmer. But it’s entirely system dependent. In the right setup it could be exactly what’s needed. I used a monster Krell 700cx 200 pound amp to drive a pair of B&W 800s for several years. They certainly woke up that behemoth of a speaker. They worked well on a pair of Magnepan 3.6Rs. Maggies are incredibly inefficient and need as much power as you can pump into them. Somewhat late in life I discovered the joys of horn loudspeakers. My La Scalas are happy with 1 watt of the highest quality SET tube power I can use. My current favorite are Oliver Sayes 421a SET that uses a single Western Electric power tube for both channels. You can’t do that with a Maggie!
Hi All, just thought to catch up on what's the best.... just in case anyone wants a visual on setup - it's pretty casual but a few have said it was useful to see:
Another note: I have had packaging redesigns worked out which hopefully will be much better, lighter and cleaner (no white styrofoam that flies in pieces everywhere) The first try will be for moving demo speakers from SL to California Audio Show next month. Photo attached to give an idea ... comments/questions welcome. This design is intended for three heights of speaker G7, G8 and G9. (all same C5 width)
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Sorry i meant to send the video to you because I think you might have been the original wondering about how to move and set up? The new packing material however would not apply because I have not yet designed and made for the standard 7 cell width model (which is your 945PX you are referring to.Folks mentioned this ad for a 945PX earlier on this thread. The dimensions look really large. I’m guessing this would require a moving company with several strong people to remove and install this speaker. Not a task for the faint-hearted!
FOR SALE: Soundlabs 945 PX speakers with full Hotrod Xformers Sound lab Martin Logan CLX big brother
Due to just honestly needing to sell these speakers. Someone is going to enjoy and love an amazing set of speakers for years to come at a price less than the last pair of just the included transformer sold for on eBay. The speakers weren't even included!!.Tested To spec, absolutely no damage...www.usaudiomart.com
Had a fair number of poweramps to sort thru before and after I received the SL M745s and just today have chosen the Pass X260.8s over the Atma-Sphere MA-1/3.1 Improveds.. BUT...I just yesterday discovered that Berning makes a 200-into-8 Z-OTL monoamp called the Quadrature-Z that I'm confident many of you know of.. Found a used pair on Audiogon, spent a few hours researching, and bought them.. They'll be shipping from northern CA Friday and should arrive in Phoenix next week while I'm in Washington's Palouse region playing fotografer.
THESE ought to be interesting!
THESE ought to be interesting!
My general experience with electrostatic loudspeakers for over 30+ years is that tube amplifiers with some real grunt sound best. My current reference is the massive Audio Research Ref 210s, which uses 8 KT120 tubes, and has a tube regulated power supply unlike the current ARC monoblocks. The Ref 210 has dethroned all other amplifiers for driving my Quad 2905s that have a very high 60 ohms impedance in the bass — this is what solid state amplifiers struggle with as their power delivery drops by half with each doubling of impedance. Solid state amplifiers are current amplifiers not voltage amplifiers like tube amps are. But the 210s generate a huge amount of heat and have a somewhat noisy fan-cooled convection system. So in the current 100-degree heat wave in the Bay Area, I use a much cooler D-Sonic 1500 watt monoblock to drive my Quads. Doesn’t sound as nice, but runs a lot cooler! For stats, you need a lot of power and so you need a few hundred watts. A long time ago, I heard a rumor that Dr. West, who designed the SL speakers, himself preferred the Wolcott amplifiers.
Hi Jeff, I would be very interested to hear your comments with the Berning. I used Ricky Brown's HiFiOne's 845 ZOTL in Dallas and also brought the amps back with me to Japan. They are about 60w Class A. I use them to run my G9-7Cs (Standard Maj945s). And I get 95db when using at about 85% power. I find that quite more than enough and I have a very large room -30'x30' with 20' ceiling and open into kitchen so actually much bigger. I was hesitant when I decided to use in Dallas, but Ricky assured me there will be no problem. Certainly no problem and sound fantastic too. Very interested to hear your experience.
Running a tube amp at 85% power is a bad idea long term. For one it’s running into distortion territory as tube amplifiers tend to distort earlier than solid state amplifiers as you approach their rated specs. They distort in a nicer way with more second harmonic distortion, but it’s still distortion. Also the wear and tear on tubes is considerably higher as you get closer to their rated power. My guess is you need at least 300 watts for your big SLs. Power is ultimately power. You can never have enough for stats (unlike horns!).
Thanks for the comment and your points noted. Time will tell, but I very rarely run it at 85%, more like 75%. Keep in mind (you may already know) - the big SLs have a higher sensitivity than the smaller ones, and all SLs run on the same backplates. It would be incorrect to think that because they are 'big' that they need more power. So actually the smaller Sound Lab with less radiating area would benefit with a more powerful amp than the large panels. Large panels (G9,G8, G7-7C) are around 90db and the smallest G5-4C is down to 86db.
I've used numerous 140W tube amplifiers for decades (ARC VT-150SE, REF160S, REF160M MkII) on two pair of SL ELS and never exceed approximately 60% of available power I'd speculate. The latest amplifiers I'm using have meters indicating "watts" and generally they are indicating around 15W (averaging) in ultralinear mode, leaving an almost 10X ratio for peaks (140W). Even in triode mode (75W available) the power available/used for adequate SPL is more than sufficient.
The GE 6550 and the KT-150 output tubes will last for years based on listening and testing them with an Amplitrex tester, so I've found tube life to be normal.
The GE 6550 and the KT-150 output tubes will last for years based on listening and testing them with an Amplitrex tester, so I've found tube life to be normal.
I think that largely agrees with my findings. The larger 2905s seem more sensitive and require less power to wake them up than the smaller 2805s. The larger radiating surface creates more sound pressure for the same input voltage, I guess. The amplifier power you need largely depends on the size of the listening room, the speaker efficiency, and the type of music and levels you like to listen at. If you listen largely to softer classical music (like chamber music), you can easily get away with a lower powered tube or solid state amplifier. If you like to crank it up, then there’s a good reason to use a higher powered amplifier rather than push your lower powered amplifier into distortion territory. For moving coil dynamic speakers, often tweeters get burned out from low powered amplifiers being overdriven rather than from high powered amplifiers. As amplifiers distort, they produce fairly high levels of high frequency signals that burn out tweeters quickly. That of course does not apply to the large SLs.
Well, realistically, the speakers have a limit too.
The bias setting one is able to set affects efficiency (and tone?).
The impedance tap used (if available) along with the Brilliance adjustment can significantly affect the mix.
I'd like to hear other SL users experience on these variables.
The bias setting one is able to set affects efficiency (and tone?).
The impedance tap used (if available) along with the Brilliance adjustment can significantly affect the mix.
I'd like to hear other SL users experience on these variables.
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FWIW Dept.: 80% of our MA-2 production is running Sound Labs. Sound Labs really do like power. The MA-2s are only slightly warmer than MA-1s because the output section is more efficient so the power tubes run cooler despite being biased exactly the same.
The Quadrature Z (hereafter QZ) amps shipped yesterday, Monday, and will be here tomorrow, Wed. the 10th; wish me luck on receiving three undamaged cartons.. Have some NOS Mullard 12AT7s coming from Brent Jesse and 16GK6 drivers coming; still looking for 33JV6 outputs.
FWIW, these QZs have the Steve McCormack (SMC) Gravity Bases installed.
FWIW, these QZs have the Steve McCormack (SMC) Gravity Bases installed.
Nice write up of the technology behind these amplifiers is given here:
One striking aspect is the use of switching power supplies, which is usually considered a no-no in the high end audio world.
One striking aspect is the use of switching power supplies, which is usually considered a no-no in the high end audio world.
Extraordinarily transparent amplifiers. On the Casino Royale Dusty Springfeild "Look of Love" (remember that one?) you could tell she used the Colgate instead of Crest.
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