Interesting , never experienced a class D do that to every BJT amplifier i have ever heard..!
Soundlab Audiophile G9-7c: a 30-year odyssey fulfilled
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Interesting , never experienced a class D do that to every BJT amplifier i have ever heard..!
Listening to a lovely old jazz recording by Milt Jackson. Many classic jazz recordings in the late 1950s-1960s were recorded by panning all instruments to the left or right channel, as is done here. There’s no genuine stereo imagery and no center fill. But even sitting off axis on my sofa pictured above next to the left speaker, the sound is like sitting off the main stage at a jazz venue. The sound gets projected out and kind of washes over you like a sonic breeze. Even an old recording like this sounds really pleasant because there’s no point source tweeter that reveals its presence by exposing the limitations of old microphones. The large radiating surface works wonders in making old timeless recordings more enjoyable.
In this era of high resolution streaming, conventional class D might be inferior to a fully digital amplifier. The major theoretical result from information theory is that it’s best to keep information in digital form over transmission through noisy channels. That’s why data to your smartphone comes in digital packets with built-in error correction. I think Tact had the right idea with its Millenium amplifier that keeps digital in PWM format and converts to analog only at the output stage using an RC network. The volume control is outside the signal chain as it reduces or increases output voltage at the power supply only. But the challenge is to maintain performance in a load insensitive manner. I do have a fully digital PWM amplifier from Lyngdorf, but it’s only rated around 80 watts. I’m not sure it’s powerful enough to drive the big Soundlab, not to mention whether it can handle the swings in impedance.
Listening to another lovely old jazz recording of Ben Webster originally made for Dutch radio broadcast and only recently rediscovered. There’s a tendency among audiophiles to test loudspeakers by trotting out audiophile classics. But the true test of a loudspeaker is how it handles a wide variety of music recorded perhaps with less than ideal equipment in strange places. If it can allow you to enjoy old vintage recordings like this one, it’s going to keep you happy for a long while. That’s what the big SLs can do. You don’t need to play the few audiophile classics. Enjoy the great old recordings. As Gordon Holt, the founder of Stereophile famously said, there’s an inverse correlation between recording quality and musical quality!
I like to end a lot of late evening listening sessions with one of my all-time immortal tunes, the sort of heartfelt mournful tune that makes you wonder how anyone can compose such music. This is the Etude for Franca, played first magnificently on the baritone sax by jazz legend Gerry Mulligan and then to Portuguese lyrics by Brazilian sensation Jane Duboc. Forget the tuneless singing of audiophile label Anna Caram. Jane Duboc’s singing on this album will set your hearts racing. One of the greatest duets ever recorded in modern jazz. Beautifully recorded by Telarc. On the big SLs, it feels like a chocolate dessert that’s over too soon!
The “king of tube amplifiers” is waiting to challenge the “king of electrostatic loudspeakers”. An audiophile “duel” is waiting for cooler weather. Can you believe that in the Bay Area, next week we are predicted to have temperatures in the 100-degree range? This duel has to await cooler weather.
I installed the optional tube grill covers on my ARC 750SE amplifiers today. Makes them look more menacing, even though the massive KT150 bank of tubes is now hidden.
I installed the optional tube grill covers on my ARC 750SE amplifiers today. Makes them look more menacing, even though the massive KT150 bank of tubes is now hidden.
Here’s a lovely chamber music recording that very helpfully gives a picture of the ensemble and how they were recorded on the front cover. A tightly clustered ensemble should be reproduced similarly. A surprising finding is that these giant speakers can sound like much smaller monitors as the recording dictates. The soundstage is not artificially blown up.
Here the clarinet is recorded on the right positioned a bit forward of the other strings. That’s exactly how it sounds. The recording was made in a church and sounds appropriately resonant. Strings are astringent when played that way and warm and full as the score dictates. The clarinetist seems like he’s hiding behind the right speaker. Quads tend to megaphone a bit, perhaps a result of the delay line circuitry. Here the soundstage remains stable even as the volume varies from pianissimo to fortissimo.
Here the clarinet is recorded on the right positioned a bit forward of the other strings. That’s exactly how it sounds. The recording was made in a church and sounds appropriately resonant. Strings are astringent when played that way and warm and full as the score dictates. The clarinetist seems like he’s hiding behind the right speaker. Quads tend to megaphone a bit, perhaps a result of the delay line circuitry. Here the soundstage remains stable even as the volume varies from pianissimo to fortissimo.
One of my favorite older Mulligan albums, Jeru. The contrast between the classical chamber music recording in a church with a single Blumlein mike setup and this multimiked studio jazz album could not be more pronounced. Here one drumkit is panned to the hard left and the other to the right, and the piano is always panned hard right. Mulligan’s baritone is mixed to the center and sounds appropriately bloated given how close it must have been miked.
One does not expect a soundstage in older jazz recordings. The instruments are miked closely. The drum kit jumps out of the left speaker. The piano is scrunched into the right speaker. Yet this recording sounds surprisingly good, the large SLs imbuing a welcome warmth to a vintage jazz recording.
One does not expect a soundstage in older jazz recordings. The instruments are miked closely. The drum kit jumps out of the left speaker. The piano is scrunched into the right speaker. Yet this recording sounds surprisingly good, the large SLs imbuing a welcome warmth to a vintage jazz recording.
And now for something completely different. Over the past several decades I have lectured on AI in several dozen countries. In the mid 1990s, I gave a series of three invited lectures on AI in Caracas, the capital of Venezuela, at a very different and happier time for that country. I always request my hosts to take me to a local record store. I picked up some lovely ethnic music and came to know of the music of Seranata Guyanese, folk music of Venezuela. This is a lovely warm recording with the voices naturally captured and the instruments bathed in a nice acoustic. The tunes are catchy. Brings back memories of a time when AI was an academic project pursued by a few of us before it became the province of trillion dollar companies.
This recording sounds lovely on the big SLs, where the natural dynamics is nicely captured. Instruments are rendered with a nice roundness to them. The four singers are nicely separated. Makes you feel you are in their “living presence”.
My favorite track is “Easter Morning”, which I play each year on Easter morning! Their English diction will either make you cringe or smile.
My original CD is not available for streaming. This is a later recording when these singers have aged. But this streaming version is a better recording.
This recording sounds lovely on the big SLs, where the natural dynamics is nicely captured. Instruments are rendered with a nice roundness to them. The four singers are nicely separated. Makes you feel you are in their “living presence”.
My favorite track is “Easter Morning”, which I play each year on Easter morning! Their English diction will either make you cringe or smile.
My original CD is not available for streaming. This is a later recording when these singers have aged. But this streaming version is a better recording.
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We now move from far away Venezuela to a lovely live jazz recording made just an hour from my house in a club called Tsubo in Berkeley in the 1960s. The club is long gone but what a concert this must have been. The music is bouncy with plenty of rhythm. If the first track doesn’t have you jumping around your listening room to Wes Montgomery’s groove, I suggest an immediate check with your cardiologist.
This is a live recording but recorded very close, so the instruments leap out at you in your face literally. In the much quieter second track, you hear the tape hiss ( or is that the hiss from possibly tube microphones). In any event, this is a landmark jazz recording, which received many critical raves.
On the big Soundlab’s, you are in the club. The audience clapping feels like a surround sound recording. This is one of those recordings when you are tempted to crank it up, so infectious is the beat. Live jazz at its best. Add this to your playlist for days when you feel the blues.
This is a live recording but recorded very close, so the instruments leap out at you in your face literally. In the much quieter second track, you hear the tape hiss ( or is that the hiss from possibly tube microphones). In any event, this is a landmark jazz recording, which received many critical raves.
On the big Soundlab’s, you are in the club. The audience clapping feels like a surround sound recording. This is one of those recordings when you are tempted to crank it up, so infectious is the beat. Live jazz at its best. Add this to your playlist for days when you feel the blues.
And we finish another listening session with a Harmonia Mundi DSD recording produced by Robina Young that could not be a bigger contrast with the raucous Wes Montgomery one just mentioned above. So much of California draws from Mexican culture. So many of our towns and cities have names like San Jose or Los Angeles. So it seems entirely apposite to end with a Mexican Mass. Recorded beautifully in a large church, the acoustic is suitably ecclesiastical. The recording is at first seemingly very emaciated: who
let the air out of the tires, you might ask. That’s because this recording sounds much more like live music than the very closely multimiked Wes Montgomery Tsubo. Here the voices are very distant. The second track has a conch shell playing far away that echoes through the church. The voices are not up close in your face.
The SLs reproduce this ecclesiastical recording so differently from the rowdy Wes Montgomery Tsubo that your first instinct is something is wrong. No, it’s just showing the huge difference a recording makes. The DSD recording sounds very analog. No digital brightness here. Very tube like. DSD recordings generally get scaled down in volume. But raising the volume won’t turn it into a rowdy jazz club. No, you have to reset your ears.
let the air out of the tires, you might ask. That’s because this recording sounds much more like live music than the very closely multimiked Wes Montgomery Tsubo. Here the voices are very distant. The second track has a conch shell playing far away that echoes through the church. The voices are not up close in your face.
The SLs reproduce this ecclesiastical recording so differently from the rowdy Wes Montgomery Tsubo that your first instinct is something is wrong. No, it’s just showing the huge difference a recording makes. The DSD recording sounds very analog. No digital brightness here. Very tube like. DSD recordings generally get scaled down in volume. But raising the volume won’t turn it into a rowdy jazz club. No, you have to reset your ears.
How are these different than the SL A-945s? Do yours include Bass Focus (pat pend?)?
Those are the older models. For the latest models, click on the link I gave on the first post in this thread. My model has the latest panel technology. The 7c indicates the extra width. Previously they typically came in the 5c width.
Note the partitions. This is why Sound Labs do not exhibit drum head resonance. Notice the lateral bisecting. The top and bottom are mirror images. Low frequencies are at the bottom and top.
Godofwealth has some great amplifiers but I want to make it clear that much power is not absolutely required. I ran my 545PX with 85 wpc from a VAC integrated. I now use 85 wpc VAC Essence 80 iQ monoblocs.
Godofwealth has some great amplifiers but I want to make it clear that much power is not absolutely required. I ran my 545PX with 85 wpc from a VAC integrated. I now use 85 wpc VAC Essence 80 iQ monoblocs.
Great picture! I like the wood on the back wall.
The manual says my G9-7c’s are rated 88 dB in efficiency. If this spec is accurate, unboxed is correct. You can drive SLs with less power than I’m using. A lot depends on the size of the room, how absorbent it is, the bias setting, and the volume levels you like to listen at. My room is fairly large and has two large overstuffed sofas, carpet etc., so it is quite absorbent. One important point about SLs and electrostatics in general is that they sound very good even at low volumes. There’s no tonal drop out at lower volumes. I’m planning to try an 80 watt Lyngdorf integrated digital amplifier at some point.
The manual says my G9-7c’s are rated 88 dB in efficiency. If this spec is accurate, unboxed is correct. You can drive SLs with less power than I’m using. A lot depends on the size of the room, how absorbent it is, the bias setting, and the volume levels you like to listen at. My room is fairly large and has two large overstuffed sofas, carpet etc., so it is quite absorbent. One important point about SLs and electrostatics in general is that they sound very good even at low volumes. There’s no tonal drop out at lower volumes. I’m planning to try an 80 watt Lyngdorf integrated digital amplifier at some point.
I heartily agree with this; I've tried 'em.. Again, the first 'best-sounding' amp for my M745s were the Pass X260.8s, and the PS Audio BHK600s proved to sound better--and simply sublime--than the Passes.. A pair of XA60.8s are on the way to evaluate; we'll see.
Have you tried the VAC Essence 80 iQ monoblocs on the different output taps? Which one do you favour?
Electrostatic Amp Odyssey:
When I had the U-1PXs in a room possibly larger than @godofwealth I found the best amps at the time were single stage Aleph monos at 100 wpc(?) - if memory serves. (A dealer lent me a Levinson stereo amp at 200 wpc that kept going into thermal overload.)
This was quite a place as I ran Balanced cables everywhere with short speaker cables. Analog sources were in another room, the TT was suspended from studs in the ceiling with XLR cables from the Aleph Ono phono preamp to the control preamp near the couch in the music room. There were open doorways into other rooms behind the rear of each speakers so I did not need to use high frequency absorption panels.
We used to have dance recitals in this room... sound never got louder only bigger just as the OP said.
Before that I had an Aleph 5 when I had Quad 63 Pros. Previously I had stacked Quads paired with two Bedini-25s replaced by two Aleph 3s. I used 18" subwoofers in all these systems but I drove the SL directly; put a low pass at 20-40 Hz on the subs. I really like the Aleph amps.
I sold the QUADs and bought my first pair of SL which I think were A-3s. Never wrote the models down...
I tried various valve amps but never had good luck with them or them with me.
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