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Tubes Asylum Questions about tubes and gear that glows. FAQ |
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Tubes Asylum Questions about tubes and gear that glows. FAQ |
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In Reply to: RE: Thoughts on the Audio Research 210 and current ARC sound ? posted by FredericB on May 23, 2009 at 05:26:01:
PHOTO: Audio Research 210 monoblock Top Right. It appears the 6-6550's- missing in this photo- are in a row on the far side of the transformers and the fan is on the inside of the back panel in line with the tubes. This owner may be using a KT88 for the regulator.
FredericB,
I appreciate your comments on the 6550's, 210, 6H30, and the new directions ARC might go with the new owners.
6550's: Yes, I think if Jim McShane can come up with 6 matched pair of the GE's and thinks the 210 won't push them too hard, they would result in sounds as pleasant as a 6550 can make. That's according though to using four sets of the GE and one of Philips ECG in a D115 and hearing the SED's in various ARC V's VT's and VS's. I knew I'd like to stick to the GE- ARC knew what they were doing when supplying those as original. Someone sat in a room with an SP10 and D115 and Wilson Speakers.
I've never bought from Jim McShane, but he's helpful here and with Citation owners and I especially trust his opinion on current production tubes. He's obviously listened and analysed these in detail and is very critical of quality control problems.
Cooling fan for an Audio Research 210: And, like audible cooling fans, this tiny detail when wrong is really annoying. And, when you know it's there, it's a sure path to audio insanity: you find yourself starting to listen for it sometimes-, thoughts of No, that was the refrigerator." will intrude on your Chopin.
As a remedial measure for your Belgian friend's 210 and it's screaming fan, I had a simple thought: use Amplifier Remote Ducted Ventilation by Extraction and Independent 12V Power Supply or, "RIAA SAE ARDVEI12VPS ART241.0AV", for short. Replace the fan with a 6" duct flange over the back panel vent, then run 3 Meters of smooth wall, flexible A/C duct- the plastic accordion type. Terminate the other duct with a round to rectangular duct. Attach to the rectangular duct box two side by side silent computer fans and power them with a 12V power supplies not plugged into the same wall outlet as the 210. A screen over the fans will keep out the cat. Place the fan ends on bracket/stands so they may be set near vertically, and run faced opposite from the listener.
Tweaker's delights: Set the ducts on risers made of ridiculously expensive materials or mount them on the wall behind so induction from the air friction can't build up a static charge next to any cables. And the rushing air might radiate mechanical vibrations,.. And, a coat of blue paint might make jazz sound smoother.
A mad idea yes, but think of the bragging rights with two large diameter ducts coming out of the back of a macho monoblock- like chrome exhaust stacks on an eighteen wheeler. And -A touch of "Brazil".
-It might even work. Watch for my new company: AirAudio featuring "Bambi B's Belgian Baffles ™©®™", 2009. Perhaps George Louis can be the fan polarity consultant and Geoff Kaitt the transverse molecular and atomic de-accelerator induction timing duct engineer.
6H30: Yes, it seems to everything well- the ARC REF 3 is very, very good and I've read positive comments on Victor's use of them in the BAT gear. It's interesting that you mention a slightly glassy top- I'd add that they seem almost overly unforgiving of the sources- I've heard the 6H30 in four or five components but in each case the least defect in the system is made obvious.
I hope I have this right that Victor said that there are in effect only two choices for the 6H30- the current production Sovtek and the NOS Sovtek "DR" made in the same factory 15 years ago. The DR must have a valuable sound quality as these are offered for $100 a piece now. The monopoly though has made the current production ones are relatively costly too-a 12AX7EH costs $11 while the same supplier gets $30 for a 6H30. They get $19 more when they call it a "Supertube". Still, I think ARC will ask your bank to send them about $75 for one of these.
I was interested to see that ARC chose to make the SP16 12AX7 retro, and all the PH phono preamps were 6922 but gave in to modernity for the SP17 and the $11K REF Phono2 with 5- 6H30's and a 6550.
ARC tube rejection rate and testing: By the way, I intend to check the dealer's comment that ARC rejects 87% of the tubes they test. He may have said this while we were talking about the selection of low noise EH6922 that are good enough for the various "ln" -low noise" phono preamp spots- and not 6550's. By reputation, my impression is that SED quality is quite good, but ARC does pride themselves on their care in tube selection:
From the ARC website:
> "Once purchased and received by Audio Research, vacuum tubes undergo exacting quality control measures to further assure reliable, sonically acceptable performance. Power output tubes -- currently 6550C and 6550EH power beam tetrodes manufactured in Russia - are first mounted in test fixtures and burned in for 48 hours. This burn-in helps stabilize the internal operating parameters of the tubes before measurements for pair-matching begin. Each power tube is then tested and graded for technical characteristics specified by Audio Research engineers. Only after a tube successfully passes these exacting challenges is it labeled and put into stock to be used in a new product or sold to the aftermarket. Tubes not meeting these criteria are rejected to the supplier or disposed of. Small-signal tubes such as the 6922 or 6H30 used in current designs are also individually tested for internal noise, microphonics, grid current and are measured for gain. Again, inferior tubes are disposed of.
# Tested, selected Audio Research tubes will often cost slightly more than generic types offered by aftermarket vacuum-tube sellers, who may not have the technical or financial ability to conduct exacting quality-control measures. These vendors also are not likely to eliminate and dispose of inferior, poor-quality tubes. For best performance and reliability in Audio Research products, Audio Research quality-tested tubes are strongly recommended.
# Audio Research tubes are selected, matched and prebiased for best performance when installed in a new or updated product at the factory. No further biasing or other measures are necessary when first installing a new-from-the-factory preamp or power amp in your audio system. "
I hadn't read this patter for a long while and am interested to see the phrase: "Power output tubes -- currently 6550C and 6550EH power beam tetrodes manufactured in Russia"- so they're supplying both the SED and EH. I think the Svetlana/SED predates the EH so perhaps they're voicing the new amplifiers for the EH.
Sorry for the very long post.
Let us know how your friend's 210 works out.
Cheers,
Bambi B
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Follow Ups
- RE: Thoughts on the Audio Research 210 and current ARC sound ? - Bambi B 05/24/0911:49:59 05/24/09 (0)
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