Clipped and Shorn Posted October 17, 2002 Share Posted October 17, 2002 I have a preamp that uses eight 12AX7s. I wanted to replace all the tubes. I happen to have a set of NOS CV4004 military spec tubes. Did I remember someone on this forum saying these could be substituted? The data from the following website seems to indicate that the tubes are not 100% interchangeable. I am not sure just when you can safely substitute tubes. http://www.duncanamps.co.uk/cgi-bin/tdsl3.exe/show?SID=0002DBFEF801AC0C&DES=CV4004 -c7s Link to comment Share on other sites More sharing options...
arco Posted October 17, 2002 Share Posted October 17, 2002 CV4004 is the British military designation for the 12AX7 tube. You can go on and substitute your tubes without worry... Link to comment Share on other sites More sharing options...
Khorn Posted October 17, 2002 Share Posted October 17, 2002 Check out this useful site: http://hereford.ampr.org/cgi-bin/tube Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 17, 2002 Author Share Posted October 17, 2002 cool, I'll plug them in and let you know how it sounds. -c7s Link to comment Share on other sites More sharing options...
mobile homeless Posted October 17, 2002 Share Posted October 17, 2002 What preamp are you now using that employs EIGHT 12AX7? Lordy, I barely like TWO in my preamp! What did you get? Link to comment Share on other sites More sharing options...
Tom Mobley Posted October 17, 2002 Share Posted October 17, 2002 Maybe he's using an old Hammond organ for a preamp? Link to comment Share on other sites More sharing options...
mike stehr Posted October 17, 2002 Share Posted October 17, 2002 The Eico HF-85 uses five with a 6X4 rectifier. Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 18, 2002 Author Share Posted October 18, 2002 "Lordy, I barely like TWO in my preamp! " Huh? -c7s I thought the Cary used a couple of 6SL7 or 6SM7 Link to comment Share on other sites More sharing options...
mobile homeless Posted October 18, 2002 Share Posted October 18, 2002 CS I am carrying this over from another thread...., btw, it sounds like you have moving magnet phono stages in your preamp options. Also, I think a really good preamp is important, as important as the amp. I remember you talking of Audio Research vintage units. I have never liked Audio Research preamps that much but the early units like the SP-3, SP-6b, and SP-8 are the least objectionable and the nicest of the lot, in my opinion. If you are going to go Audio Research, youre in the right camp. Judging by the 8 12AX7, it sounds like you might have the SP-3 which many like. The SP-3 does have a MM phono stage. Regarding your other cartridge questions, to run a low output MC, you would need a stepup transformer or different phono stage. Also, to be frank, you would probably need a new table as the Technics 1200 mkII just doesnt have the tonearm and setup for a something like an MC. I read your comments about the 1200 Mk II and know your feelings on the table. I have more experience with THAT table then just about any table besides the Linn LP-12. It is a more or less bulletproof table that DOES have some good features. But it does have some drawbacks when moving into the next level. I used them, set them up, mounted dozens of catridges, and played or listened to them over 8 hours a day for about 8 years. I have had this table at home and at work and in my office. I have used it with DJ strength cartridges up to the HO MC basic Blue Point, Signet TK-7, and more many of the Grado line during the 80s and early 90s. You are moving to ALL tube components. Solid state was just not getting if for you. I understand this completely. Now here is the clincher. Moving from the 1200 MkII to a good turntable with belt drive, excellent motor, platter, and quality tonearm with cartridge is almost EXACTLY the same comparison to moving from good solid state to tubes. Many of the same rewards are gained, and this has NOTHING to do with "audiophile" this or "snob appeal" that. It is a distinctive difference in the presentataion and quality of the playback and you dont need to spend big money to get there. The 1200 MkII offers really buttoned up, fine sound and has a lot going for it. But compared to other tables, some even costing LESS, you will gain more richness, more of an expansive soundstage, and a more liquid quality to the playback. In short, it will sound more lush and real with more dimension. And I DO respect the 1200 mkII for what it can do (the arm DOES have a neat VTA adjustment ability on the fly). I carried a pair with me in my car for every remote station broadcast and loved them for their great attributes. But compared to others, the sound is more flat and not as expansive. The tonearm is not really setup to use MC cartriges. It did do pretty well with the high output Blue Point MC (regular). This rather tube-like, more lush cartridge was a better match than the standard fair. Jazman gave a good rec with the Dynavector 10X4. I also like the original Blue Point but the lowest I have found it is on sale at UltraSystems for $178. The Denon DL-110 is also a nice cartridge but hard to locate. You have to buy from overseas more than likely and it will run about $100-130. A pure MC cartridge really does deliver some of the most musical sound with a richness, warmth, and quality that escapes most MM. But as stated, you will need a stepup transformer and better tonearm to deal with some of the better MC. And also, the damn things are expensive. Cheaper good sounding ones include the Denon DL-103. The 103 does great with Jazz. And there are others as well. The SP-3 is supposed to have a very sweet (for AR) sounding phono stage. kh Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 18, 2002 Author Share Posted October 18, 2002 kh, Thanks for all the good information. I will be interested to research moving up regarding the turntable. Be thinking of suggestions which could come in for under 1k. The turntable improvement would probably benefit regardless of the Cartridge I decide upon. There is the matter of my playing a certain number of LPs with much surface noise, and there is the possibility of having more than one turntable set up in my system to accomodate this. Then again, one might be of the opinion that one should extract the best sound possible from ANY source LP regardless of the fact that a MC will further add extra amplification to surface noise {LPs=G to VG}. What do you think of the idea of having maybe one TT/Cart set up for noisy LPs and a higher end TT and Cart set up for all the great NM to VG+ vinyl in my collection. Yes, I have an old Audio Research SP-3 on hand. {I knew you would deduce that so I let you get those points and the trip to Bermuda and the Car). Actually this unit might possibly be used as a back up or in second system in another studio, if I decide to keep it -- they are easy enough to sell on eBay, who knows it might even need to go back to AR for an upgrade being as old as it is. The preamp I have currently have set up is an improvement on the SP-3, yet another 8x12AX7 rig, a vintage Paragon, which sounds really wonderful with a set of fresh Telefunkens. This one is a keeper, for the moment, and I will use it for the upcoming Tri-Amp monster I am planning -- just as soon as I can clean up my shop {get all the crap off the table saw} and start building those speaker cabinets which I fear might be a tad on the heavy side what with each containing two 15 inch Altecs and a 511 horn and driver in addition to all the plywood and bracing ---scarry, to think of moving these things into the house! {at least they will be desiged to fit through the door} ...man, I better think about this....maybe I should build them in the shop sans speakers, then move the cabs into the house and install the components there, hmmmmm? So why do I have this growing collection of vintage gear? Seems like I am more willing to purchase in drips and drabs what seems like bargains along the way than to spring for the slightly larger ticket items in one gulp, even though the serial nature of these purchases results in the same expenditure. I guess I want to go through the learning process and have some soldering fun and make mistakes. Maybe I am addicted to nervous breakdowns and frustrating crises? On the other hand, your thorough testing and experience with the Technics might just provide me a short cut to your conclusions. My main point about it was that the speed was dead on, but you are correct the isolation and arm and other "high-end" considerations are apparently compromised compared to others. So, if you were in the market today for a turtable, what would you be considering? Remember, I like to think I am getting the best bang for the buck. -C&S also, thanks for your appreciation of the ongoing avatar art show.....as a graphics man, I know you have the eye..... Link to comment Share on other sites More sharing options...
mobile homeless Posted October 19, 2002 Share Posted October 19, 2002 Good tables and cartridges actually can reduce the background noise ie tics and pops. This is a common misconception that better cartridges and tables increase noise in poor records; this is not always the case and I have actually found the opposite to be true. The better the table and setup, including VTA and Azimuth adjustment, and the better the stylus/cartridge, the better that noise floor and in many instances, the better the play of less quality vinyl. Admittedly, the phono stage also plays a role here, especially when you move to the MC cartrigdge, where the phono stage starts to become extremely critical (there is MUCH more amplification going on with a .2mv output). As for new tables, one of the best deals going on right now is the Music Hall MMF-7 from Underwoodwally in Atlanta. This gives you a separate motor housing not even connected to the platter/chassis/subchassis, hence the motor noise not being transferred to the cartridge/arm and into the chain. The ONLY downside for this table is the dedicated arm per say. The good thing? The Project 9 arm is a VERY good arm! IT has VTA adjustment on the fly and decoupled counterweight etc. Very rigid ONE piece headshell and tube (much better sonicially than a sep headshell). It has a good platter, and is a split plinth design with cone feet on the bottom plinth and sorbathane coupled between top and bottom plinth. The next GREAT thing about this table is that it comes with the Goldring EROICA HO MC cartridge PRE-MOUNTED. This is a $400 cartridge on its own and it comes with the table for truly an excellent buy. The Goldrings have really warm, musical sound. This table has received NOTHING but positive comments and is supposedly MUCH better than the MMF-5 and the super budget MMF-2.1. Chris Robinson just bought this table. At $750-80 with FREE Shipping, it is a GREAT deal. Subtract that cartridge amount and you see how GREAT a deal it is. I'll do a used table roundup in my next post. Right now, at that price above, I dont see anything in the range new that competes. I dont think there are any other tables with stand alone motors anywhere near this range. A lot to spend? Given your collection , I think it's not much at all. And the sonic jump from the used Thorens, Duals, etc is GREAT. Quite a few on the Vinyl Asylum have upgraded from Thorens to this deck. Much quieter background.... kh Link to comment Share on other sites More sharing options...
NOSValves Posted October 19, 2002 Share Posted October 19, 2002 Mobile, Now that looks like a incredible deal and something I may consider as a Xmas gift to myself if finances improve from the winter Home Improvement rush !! I'm so into Vinyl I think I will take others advise here and sooner or later buy a High Quality table and quit messing with the used abused crowd LOL ! I have a few questions. This MC cartridge issue ? My Scott has High and Low Inputs on pickup 2 for Phono cartridges would one of these be the proper setup for a MC cartridges ? I currently use Low input on Pickup 2 for my MM cartridges ? The Scott manual say's that Mag 2 high is for Ceramic or Crystal cartridges . Also this deal you speak of do they offer this table with some other cartridges possibly that are not MC if the Scott can't use a MC cartridge ? Craig Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 19, 2002 Author Share Posted October 19, 2002 Music Hall MMF-7! Wow, I am all a flutter. This sounds like it is exactly the turnable that someone I met while out record scrounging was fruitlessly trying to remember with his likewise geezer memory. All he could come up with was that there were a lot of "M's".... I tried to do a google search knowing only that there were a lot of "M's" but could not find it that way. I was almost going to post something on this forum, something like, who knows a good Turtable with a lot of "M's" in the name. But low and behold, you, in all your beturbined Karnakian psychic splendor have divined the answer........ Now you say: "not quite, vintage capacitor breath"..... I think it is a go. -C&S Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 19, 2002 Author Share Posted October 19, 2002 Craig, I believe that the turntable comes already cartridge installed. The good news is that it is a High Output Moving Coil which means you can connect it to an MM input on your Scott. But that is a good question about whether one can choose another cartridge. Could be that the Goldring is every bit as good an answer as the Dynavector DV 10X4 MKII that Jazman had recommeded to me. I think I will google search this out. -C&S Link to comment Share on other sites More sharing options...
NOSValves Posted October 19, 2002 Share Posted October 19, 2002 clipped, Well that's great to know. Do you think you may get this table ? Is there a website for the company that is selling this ? What about this table any good ?? SUMIKO Project 6 Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 19, 2002 Author Share Posted October 19, 2002 Craig, Here are some links, mmmm...... http://www.responseaudio.com/hall_n_creek1.htm http://www.needledoctor.com/showcat.cfm?catnum=1&parentcatnum=1 http://www.needledoctor.com/showitem.cfm?catnum=1&parentcatnum=1&itemnum=1641 http://shop.store.yahoo.com/decibelchicago/mushalmmf7tu.html It looks good to me, and there are so many out there with positive recommendations. -C&S Link to comment Share on other sites More sharing options...
Clipped and Shorn Posted October 19, 2002 Author Share Posted October 19, 2002 Here is a Sumiko TT in a comparable price range, probably sans cartridge tho. http://www.needledoctor.com/showitem.cfm?catnum=1&parentcatnum=1&itemnum=52 You can read about all of these at one of those links I posted. Maybe someone on the Forum can comment on the Sumiko. I didn't see the "6" on the list. Maybe it is a discontinued model or something. -C&S Link to comment Share on other sites More sharing options...
jazman Posted October 19, 2002 Share Posted October 19, 2002 Clipped and Craig, Shapeshifter(Wes), has had this table/arm/cartridge combination for some time and I believe he is very pleased with it. Send him an email to get all the details. The installed cartridge is a good one, certainly worth keeping and better than the Shure M91 series. I have not read a negative review of the MMF-7. Klipsch out. Link to comment Share on other sites More sharing options...
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