Bernard
Well-known member
Amp Manufacturer: Audio Research Corporation
Model: VTM 120 Monoblocks
Manufacturer's Suggested Retail Price: Unknown
Used market average price: $2,000/pair
Basic Specs: 110 watts/channel
I first fell in love with electrostats when I heard and bought the Quad 57’s. After a few amplifier upgrades I ended up with the 50watt/channel Copland CTA504 power amplifier; it had gobs of power for the Quads. When I then heard the SL3’s, I decided I had to have them. The Copland made the SL3’s sound really good in the mids and the highs, but I was never satisfied with the bass. I assumed I had insufficient power, so I borrowed a 100watt/channel SS amp from my friendly ML/Copland dealer. It did bass much better, but I was missing the tube magic. So the logical thing to do seemed to be to buy a higher-powered tube amp. I could not afford to buy anything new, so I kept my eyes peeled on Audiogon for good deals. Having heard ARC’s VT100 series, and having liked it, I thought ARC may be a good idea, but I could not even afford a used VT100.
After months of patiently scanning Audiogon, I finally came across a pair of ARC VTM120 Monoblocks (110 watts), and they were going for a reasonable price too. The seller was getting rid of them as they were not compatible with his CLS. He was in Toronto, so my wife and I drove there, arriving late and starving, so I did the unthinkable – I did not ask to listen to them, but instead bought them unheard, then rushed off for a great meal. They were reasonably priced, so I figured I could always sell them if I didn’t like them.
I took them home and hooked them up to my SL3’s. First task was checking the bias. The guy who designed the layout of the board should be shot; when trying to reach an awkward place partly under the top plate to attach the test clips, I got zapped. It happened with both units, so I took to powering down to attach the test clips. You set one bias pot for all 4 tubes.
After some warm-up time and bias adjustments, I set back to listen. There was the bass that was previously missing. And the treble and mids seemed to open up more than they did with the previous unit. Now I could hear what the SL3s were really capable of. Having a Koetsu in the front end did not hurt at all.
The music seemed to develop freely, without any sense of strain or hardness. Now I could hear music that was free of the boundaries of the speakers. I heard instruments being projected from a few feet behind and to the left of the left speaker. The depth of the soundstage also seemed to increase. Everything seemed much better, top to bottom.
On Track 3 of the Virginia Rodrigues “Nos” CD I could hear her moving her tongue in her mouth; really interesting when you realize what you just heard. Towards the end of Seiji Ozawa’s performance of Carmina Burana (just before the Finale), when the orchestra and chorus are building into a climax, there is a single orchestral bell that floats freely above the thick orchestral texture; the monoblocks handled that bell superbly.
Female vocals were handled as they should be: Soledad Bravo from Venezuela has a voice that gets husky and rough, and it is presented in just that way; no sugar coating here. On the other hand, Dame Emma Kirby, of whom a reviewer said, “methinks she has a brace of pigeons in her breast”, comes across with sweet, dulcet tones on the “Feather on the Breath of God” recording. But, the former was a CD while the latter was an LP. Perhaps when I do some tube rolling in my PrimaLuna CDP CDs will sound better.
I did say that the bass was better, but it was not perfect. The system just could not handle the lowest lows of “Also Sprach Zarathustra”, but then I do not often listen to power music like that. For my application (classical, Latin, Latin Jazz, Female Vocal) the system satisfies my requirements as I do not listen at the ear-bleeding levels so beloved by some audiophiles. It always amazes me when audiophiles treat tinnitus so casually.
A recent retube, with ElectroHarmonix driver tubes and SED “Winged C” output tubes (6550’s), took the system to a new level. Everything seems even more open and clean. Tube aging happens so insidiously that we never realize it until we change tubes.
The amplifier is transparent enough that it makes changes in the upstream components easily noticeable. Recently, while awaiting longer Cardas Neutral Reference interconnects (as I had moved the equipment stand to the side), I used some “commercial grade” (aka el cheapo) interconnects. On substituting the Cardas the improvement was immediately obvious.
I am happy with the amplifiers, but I should really listen to more. If I had the financial means to upgrade now, I would keep the amps and upgrade the speakers instead, or maybe I would look higher up in the ARC line than my SP9 (a PH7/Ref 3 combo perhaps). That, of course, would come after some much-needed room treatment.
Model: VTM 120 Monoblocks
Manufacturer's Suggested Retail Price: Unknown
Used market average price: $2,000/pair
Basic Specs: 110 watts/channel
I first fell in love with electrostats when I heard and bought the Quad 57’s. After a few amplifier upgrades I ended up with the 50watt/channel Copland CTA504 power amplifier; it had gobs of power for the Quads. When I then heard the SL3’s, I decided I had to have them. The Copland made the SL3’s sound really good in the mids and the highs, but I was never satisfied with the bass. I assumed I had insufficient power, so I borrowed a 100watt/channel SS amp from my friendly ML/Copland dealer. It did bass much better, but I was missing the tube magic. So the logical thing to do seemed to be to buy a higher-powered tube amp. I could not afford to buy anything new, so I kept my eyes peeled on Audiogon for good deals. Having heard ARC’s VT100 series, and having liked it, I thought ARC may be a good idea, but I could not even afford a used VT100.
After months of patiently scanning Audiogon, I finally came across a pair of ARC VTM120 Monoblocks (110 watts), and they were going for a reasonable price too. The seller was getting rid of them as they were not compatible with his CLS. He was in Toronto, so my wife and I drove there, arriving late and starving, so I did the unthinkable – I did not ask to listen to them, but instead bought them unheard, then rushed off for a great meal. They were reasonably priced, so I figured I could always sell them if I didn’t like them.
I took them home and hooked them up to my SL3’s. First task was checking the bias. The guy who designed the layout of the board should be shot; when trying to reach an awkward place partly under the top plate to attach the test clips, I got zapped. It happened with both units, so I took to powering down to attach the test clips. You set one bias pot for all 4 tubes.
After some warm-up time and bias adjustments, I set back to listen. There was the bass that was previously missing. And the treble and mids seemed to open up more than they did with the previous unit. Now I could hear what the SL3s were really capable of. Having a Koetsu in the front end did not hurt at all.
The music seemed to develop freely, without any sense of strain or hardness. Now I could hear music that was free of the boundaries of the speakers. I heard instruments being projected from a few feet behind and to the left of the left speaker. The depth of the soundstage also seemed to increase. Everything seemed much better, top to bottom.
On Track 3 of the Virginia Rodrigues “Nos” CD I could hear her moving her tongue in her mouth; really interesting when you realize what you just heard. Towards the end of Seiji Ozawa’s performance of Carmina Burana (just before the Finale), when the orchestra and chorus are building into a climax, there is a single orchestral bell that floats freely above the thick orchestral texture; the monoblocks handled that bell superbly.
Female vocals were handled as they should be: Soledad Bravo from Venezuela has a voice that gets husky and rough, and it is presented in just that way; no sugar coating here. On the other hand, Dame Emma Kirby, of whom a reviewer said, “methinks she has a brace of pigeons in her breast”, comes across with sweet, dulcet tones on the “Feather on the Breath of God” recording. But, the former was a CD while the latter was an LP. Perhaps when I do some tube rolling in my PrimaLuna CDP CDs will sound better.
I did say that the bass was better, but it was not perfect. The system just could not handle the lowest lows of “Also Sprach Zarathustra”, but then I do not often listen to power music like that. For my application (classical, Latin, Latin Jazz, Female Vocal) the system satisfies my requirements as I do not listen at the ear-bleeding levels so beloved by some audiophiles. It always amazes me when audiophiles treat tinnitus so casually.
A recent retube, with ElectroHarmonix driver tubes and SED “Winged C” output tubes (6550’s), took the system to a new level. Everything seems even more open and clean. Tube aging happens so insidiously that we never realize it until we change tubes.
The amplifier is transparent enough that it makes changes in the upstream components easily noticeable. Recently, while awaiting longer Cardas Neutral Reference interconnects (as I had moved the equipment stand to the side), I used some “commercial grade” (aka el cheapo) interconnects. On substituting the Cardas the improvement was immediately obvious.
I am happy with the amplifiers, but I should really listen to more. If I had the financial means to upgrade now, I would keep the amps and upgrade the speakers instead, or maybe I would look higher up in the ARC line than my SP9 (a PH7/Ref 3 combo perhaps). That, of course, would come after some much-needed room treatment.
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