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Good morning, I have the opportunity to purchase either the Siemens 2 mica or 3 mica version's of 12at7's (matched pair's, one to use, one as a spare). My quandry is this, the seller say's the 3 mica sounded as if he were listening to a good hi-fi and the 2 mica sounded as if the musicians were in the room with him. Since I can't A/B them in the SP-8 MkII, I have the quandry. The piece of equipment he based his listening opinion on was/is a Jolida 502, if memory serves me correctly. I'm looking for a little guidance here, I guess.
Thanks,
Chris
Follow Ups:
PHOTO: Three kinds of Siemens E81CC: L> R : Two mica, Two mica/double getter support, and triple mica
dmzwizard,
I have tried the Siemens two mica ECC81, two mica 12AT7WA, Siemens E81CC/6201 2 mica and the Siemens triple mica E81CC- which may also be labeled 12AT7WA (6201) and of all, the triple mica E81CC is among my three favourite 12AT7's of the many kinds I have:
12AT7 [8] 2, 2, 1, 1, 1, 1 > TOTAL: 89
Siemens & Halske E81CC- 3 mica- DE- NOS
Siemens & H- ECC81- NOS
Valvo 6201–White label- Hamburg- gold pin -NOS
Mullard M8162- UK- NOS
Sylvania GB 6201-steel pins- NOS 124/120,120/118
Sylvania GB 6201 gold pins- US- NOS
Amperex Bugle Boy-France- NOS
GE 6201 5 star- 3-mica- NOS
RCA -HP- NOS
RCA 6201 2-mica black plate- NOS
Sylvania JAN 12AT7WA 3-mica 1958 -NOS
Sylvania 12AT7WA-Gold Print- 3 mica -USED
GE -NOS
Westinghouse- black plate-NOS
Telefunken ECC81- USED
Philips JAN- NEW
ARC -RFT- USED
GE 6201- 3 mica, sq gtr- NOS
Telefunken ECC81- NOS
Siemens&H-12AT7WA-3 mica-1-dbl gtr sup-DE- USED
Siemens-12AT7WA- 3 mica- single gtr sup- DE- USED
Sylvania JHS 12AT7WA 3-mica, bl pl, sq gtr -NOS
Raytheon JHC 12AT7WA- blk plt 3-mica- NOS [*5
Raytheon JRO 12AT7WA halo gr plt 2 mc-NOS [*5
Siemens ECC81 by RFT- military label- USED
Telefunken ECC81 by Siemens & H- Munich- USED
Valvo ECC81- Mullard Blackburn UK- USED
TungSol 6201 2-mica, grey plate-halo- NOS
Valvo 6201 Hamburg gold pin- dimp- DE- NOS [20
Siemens E81CC/6201 2 mica- stl pn- DE- NOS [13
Valvo 6201, Blue- 2 mica g pin- halo-DE ‘64- NOS [27
Siemens & Halske E81CC- 2 mica- DE- NOS [15
Telefunken ECC801S- NOS
Telefunken ECC81- NOS
It's the energy and effortless, detailed, punchy, transparency of the Siemens triple mica E81CC that I like so much. Excellent in modern gear, and can help wake up sleepy, dark, or warm vintage too. The Siemens is one of the two 12AT7's that I bought enough NOS to use in all 8 positions where I use 12AT7 (the other is the romantically wonderful Sylvania triple mica, square getter 12AT7WA). My other top 12AT7 choice is the Valvo, Hamburg 6201, which is wonderful in every way- not as "enthusiastic" as the Siemens.
Actually, the ordinary Siemens ECC81 and the two mica E81CC/12AT7WA/6201 are very good, but, for me, the triple mica E81CC is among the very best of the type I've heard.
So, how's the SP8 going for you so far?
Cheers,
Bambi B
Bambi B,
Its doing well. I've placed an order or two for some of the tubes on the list you forwarded to me and they should arrive sometime next week.
It sounds wonderful now, but I think rolling some better tubes into it will help get me closer to where I want to be with the sound of the system. I've got to get some better IC's from pre to amps than the old ones I have. It is a far distance to the amps, around 22 feet, by the time one takes into account routing/slop space. Not sure what to do yet, probably make them myself out of Belden and Eichmann.
I feel like a babe in the tube forest, when it comes to all the ones you have tried. I have yet to meet or speak to anyone who can come close to your knowledge. You are amazing and I appreciate your help and advice greatly. I'll keep you posted on the results and once again, thanks so very much.
dmzwizard,
I have spent a lot of time with 12AT7's, only keep in mind I have not tried various 12AT7s in the SP8- it has it's original Siemens ECC81 in good working order. So I'm clear on this aspect of tube choice, my choice of the Siemens triple mica E81CC is based on it's sound and performance in other gear- mainly the microphone preamp where I done the most tube fussing.
In my view, the 12AT7 may or may not make a substantial difference in the sound of your SP8 system. For example, if budget is a concern, you might try a GE five star 6201- a $15 tube NOS for the SP8's 12AT7.
However, I use the Siemens E81CC and a Siemens triple mica E82CC (12AU7) in other non-sonically critical uses such as the MPX section of a McIntosh MR67 tuner. There's a Siemens triple mica E81CC in the power supply of the ARC SP10, because it is quiet, typically has well-matched sections, and is a 10,000 hour rated tube.
My view is to use premium rated tubes where ever I can:
E83CC, ECC803S for 12AX7
E81CC, 12AT7WA, and 6201 for 12AT7
7316, E82CC, 6189, and 5814A for 12AU7
7643 and E80CF for 6BL8
7543 and 6136 for 6AU6A
Economically, the difference in cost over the years they last- especially in preamps and tuners is not worth fussing over. Of course, some tubes became ridiculously expensive, like ECC803S, E88CC/6922 and E188CC/7308, but, with careful shopping and consideration of their use, it seems possible to have a very standard of tube for the job at reasonable cost.
You mention needing interconnects and though I don't know what components your system has in it, I've had wonderful luck with Audioquest King Cobra and AQ Diamondback IC's the last 4 years in my office system:
Cambridge Audio 640C CDP, McIntosh MR67 tuner > ARC LS3 > D130 > Infinity 360's.
They take some 40-50 hours to break in and an hour to warm up, but especially the King Cobra is terrific and I have 5 1M pairs. I would think that appropriate quality 22' interconnects will tend to "add up". The longest interconnects I use are from my computer sound card to the office system and these are 4.5M (14'?) Audioquest G-Snakes which I bought off Ebay new for I think $25 with shipping. However, the quality in AQ wires I'd suggest would be Diamondback or above.
I'm a big fan of Kimber 4TC and 8TC speaker cables and in the future would like to save up and try a good Kimber IC between the Oracle III/SME 5 turntable to the ARC SP10. I've heard Kimber IC's in audio boutiqueries and show systems and if I'm discerning the cable sound correctly there's an attractive refinement in Kimber wires of all kinds.
You mention Belden DIY ICis, look for Jon Risch "recipes" using Belden LAN wires. And, I think Blue Jeans Cable amy still sell the stuff to make IC's:
http://www.bluejeanscable.com
It's always been counter-intuitive to me- as the signal from preamp to power has so much lower current than between power amp and speakers, but I've heard many times that long interconnects are preferred to long speakers cables.
Very glad to hear your SP8 is attracting you enough to want to pursue it's improvement. It is one of the really good ones in my view.
Cheers,
Bambi B
if money is tight, but get both if you can :)
I personally prefer the triple mica Siemens; it's got more detail and frequency extension, which works great in my SET. If the gear is already on the hard/bright side, double mica may work better..
I have taken your and Bambi B's original advice and have placed an order for the Siemens 3-mica 12at7's.
Looking at the schematic for the SP8 (link below), I don't see any ECC81/12AT7 used anywhere.
In what position are you using it?
Regards, Allen (Vacuum State)
PHOTO: The "Red Board" Audio Research SP8. The Revision 4 through 7 uses a 12AT7 which is the tube in the centre row at the back "V8"Allen Wright,
The Audio Research SP8 had several versions or "Revisions"
Revisions 1 through 3 were later often called "MKI" and included:
SP-8 Rev 1> 3 or "MKI": (2) 12AX7 LN, (3) 12AX7, (2) 6922, (1) 12BH7
("LN" means "Low Noise")
-and Revisions 4 through 7 were later often called "MKII" and the tubes within are:
SP-8 Rev 4> 7 or "MKII": (2) 12AX7 LN, (2) 12AX7, (2) 6922, (1) 12AT7, (1) 12BH7
V1 12AX7 phono
V2 12AX7 phono
V3 6DJ8
V4 12AX7 line
V5 12AX7 line
V6 6DJ8
V7 12BH7
V8 12AT7V1, V2, and V3 are parallel and on the right side V1 at the back
V4, V5, V6 are parallel and along the front, V4 is the left
V8 is in the centre towards the back, V7 is towards the front
My 1983 SP8 was upgraded in 1985 from Revision 2 to Revision 4 using the "Red Board" upgrade of which I was told 50 were made. For unknown reasons, the red board version has a certain following- in Asia I think. So, originally my SP8 did not use a 12AT7- then after the upgrade, it did. I seem to remember our friend dmzwizard saying he'd bought an original Rev 7, the last version.
The last two versions- (dark green boards)- Rev 6 and 7 can be spotted by the white Wondercaps in place of the orange Spragues. That was done at the dawning of the proliferation of all the boutique capacitors.
The 12AX7s are of course the Phono and Line Stage gain tubes and I think the 6922s are cathode followers. I would be be interested to learn what the 12AT7 and 12BH7 are doing for a living- I've assumed something in the power supply. The SP10, made at the same time, uses it's 12AT7 on the power supply chassis.
Confusing with all the Revisions !
Cheers,
Bambi B
Edits: 05/02/09
Bambi B and others,
This SP8 MkII has the pale green circuit boards and its serial # is 46121016. Where this falls into the run of revisions is unproven to me. I was told that it was a revision 5 by the seller and I had no reason to doubt him. I suppose I should contact Leonard at ARC tomorrow and get the revision 5 authenticated, as it were. As to the caps, this one has Nichicon's in it. The presence of these may help establish its chronology.
Bambi, I notice no presence of tube damping devices in your SP8, do you like them, not like them or just removed for the photo? and do you use anything special under, meaning feet, spiles, etc., the SP-8? I just added silicon o-rings, two per tube, to this one but have not made a deternination yet. Oh, by the way, I have an Oracle Delphi turntable, its a MkII not a III as yours is, at least in the system you refered to in a previous post.
PHOTO: This is an embarassing photo I took when I was packing to move- about 2001. On the upper left is a dusty Oracle III/SME V, below is the McIntosh MX110 I used as a tuner from 1990 to 2004, below that, the ARC D115 amplifier, a Nitty Gritty record cleaner, and on the right, the ARC SP10 with the power supply chassis under. On the right top is a failed experiment, a Pioneer 434 DVD player as transport with an ART DI/O as DAC. This failed to make digital lock 1 in 3 times, the 10V output of the ART was ridiculously high and was so annoying I used this probably only 20 hours. I've never had a CD player in my main system again, only the office.
dmzwizard,
SP8 Revision Numbers: Yes, if you give ARC the serial number, they'll give the SP8's revision number. When you check this, you might also want to verify that you have the correct manual.
Actually, the photo I posted is a "Red Board" SP8 like mine, but is from the ARC Database Site. I should have made the photo attribution clear.
Tube Dampers : As for dampers, I use two ARC rings on all the gain tubes (E188CC and 6H23p-EB) in the SP10, but in the SP8, I use one ARC ring on each of the two Phono stage 12AX7s only. When I revive the SP10- it needs a new gain pot, cap check, and some tubes before I can use it- I'm thinking to try Herbie's dampers- and for that I'll need 6.
Vibration Damping : I have usually used the SP8- and SP10 set on industrial metal shelves- that are stupidly resonant. Tap on these and they ring, ring, ring. To compensate, I place a plain rubber welcome mat from the hardware store on the shelf and then take granite cutouts for sinks- the stone contractors give these to me- and set the granite slab on the welcome mat on the metal shelf. You can see these slabs and mats just barely- in the photo above. The damping is very good- rap the shelf and it makes a very dull thump. The granite slabs- all different colours with the rubber mats peeking out under the various equipment make for an interesting appearance.
Oracle Turntables : My first serious turntable- 1985, replacing an early 70's Technics SL-D2 with a Shure V15, was an Oracle Delphi MKII with an Alphason arm. The Oracle was so good that after I moved to the SP10, I replaced the MKII, with the Delphi III with an SME V arm and Audioquest 200 cartridge. After I move early next month - the 5th time in 7 years, I intend to revive the Oracle with a new cartridge- possibly a medium output Dynavector MC, a new mat, belt, and possibly new arm wiring. The Oracle/SME is simply amazing, and the most exotic looking audio I have.
Cheers,
Bambi B
Bambi B
Judging by the photo, we have the same record cleaning machine (Nitty Gritty 1.0 or 1.5?). My current issue, actually long-standing, with the Oracle Delphi Mk II(currently not in operation due to the situation below) is that my Technics EPA-100 (not Mk II, unfortunately) tonearm is of sufficient weight that neither spring in the tower is correct to allow the proper amount of adjustment. One spring is too stiff, the other almost too weak, which can cause the tower to collapse, if not adjusted "just so". I'm told that modding it up to the Mk III, new towers etc., would eleviate the problem but I have no real proof of that, and considering the $450.00 cost, well... I'd like to rewire the arm with Cardas or Nordost but I need to deal with the tower situation first. So much to do, never enough time or money, but that's what keeps it interesting, is it not?
PHOTO: The dusty Oracle Delphi III/ SME5/ Audioquest 200 sitting on marble and a welcome mat!
dmzwizard,
Yes, I find the "little worlds" of high performance anything always interesting, whether cars, musical instruments, or audio.
With the Oracle III, I too have had set up problems. The SME V arm is tapered in such a way- it gets fat quickly- that the tube may be hit- bounced up by the record when the playback is near the end and the tonearm is swung across the LP to the centre. Adjusting the height so the SME is high enough to miss warped records puts the angle of the stylus out! And, as you mention with your Technics arm, getting the suspension adjusted right is also difficult- well, let's say it takes care and experiment.
I expect that putting my Oracle in order- new cartridge, wiring, belt and mat will be on the order of $600. Still, that's the world of high performance stuff- one can't take the Ferrari F40 to the local Brake Masters to rebuild the carbon-fibre rotors!
Cheers,
Bambi B
Bambt B,
The local brake shop would be the last place I'd take an F40 or any other prancing horse or raging bull for that matter. I'd either fix it myself or take it to the Ferrari/Lamborghini dealer. You have to pay to play as the saying goes. Hi-end audio is no different. TAG/McLaren, the cars and the audio equipment, interesting how intertwined they are sometimes. I've read, on more than one occassion, of the song a twelve cylinder Italian engine sings. I have heard them on rare occassion and they do indeed sing a most wonderous tune. Perhaps one day we can be the people pushing the pedal that makes the redhead sing her sirens song, with the open road stretched out before us and a full tank of gas. Ah, to sleep, per chance to dream...
With warmest regards,
Chris
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