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Wondering what people are happy with for this use...
Additionally, what about 5751 for preamps?
Thanks!
Follow Ups:
I think the best is the Telefunken <> base ECC801S there are still plenty around, but pricey, also I recommend the CV4024 Brimar made, or the 6201 triple spacer D or O getter. There are many variants of the 6201/12AT7WA variety available on the market. There is also a wierd version that we have that has a small triangle on the base between the pins, I have only ever seen this on the RCA Command type.Nicolas
I agree the Tele ECC801s is probobally the best of the best but if you can find one,try a united electron 12AT7.They are great for certain applications.I've only seen 2 of these and they have beautiful smooth plate construction.Sound great in guitar amps,very smooth.Bobby C..
Sarge,It's a little difficult to narrow it down without an idea of the equipment or sound you're after but my preference for my microphone preamp, McIntosh MX110, and ARC SP8 preamp has been the ordinary Siemens ECC81- clean, smooth, natural, neutral. For a very punchy, clean sound there is the Siemens E81CC triple mica- sharp! For a very lush sound, I like the triple mica military Sylvania 12AT7WA from the 50's. For a full midrange: Mullard M8162. For a nice bass and 'fast' sound, the GE Five Star 6201. The GE 6201 is a good value- great sounding for $12-15.
The 5751 is a favourite substitution for the 12AX7 and I got a nice pile of the old Sylvania black plate, square getter model. These are very, very nice is every way. I don't have experience with the other variants since this one was so, so good. I never had a problem over the slightly lower gain, but that might be a factor in a phono stage. If you want to experiment with 5751s there are the common GE and Sylvania JANs (Joint Army/Navy) at a low price and these are both good, especially if not in critical places.
Cheers,
Bambi B
Hi Bambi - long time no see! Welcome back. Can you hear a difference when changing the AT7 or BH7 in your SP-8? I finally got mine sounding as good as the 'ol SP-3A-1 I used for so many years!! I didn't think the V7 and V8 in the SP-8 would affect what we hear since they're in the power supply and not the signal path. But remember I'm the one here who can't quite follow those schematics. Nice to 'see' you again. scruff
Scruff,Hello! Great to see a familiar name- not so many since I was around last time.
With the 8, I did hear something when dealing with the 12AT7- not so much sonically, but it was a little more dynamic with the Siemens than with the black plate Westinghouse and black plate GE I tried. I knew these two were not great sonically from my trials in the Peavey VMP2 mic pre and was curious if this would affect the SP8. There was just a little more effortless quality with the Siemens- more steam. I tried one of the Siemens E81CCs and there was no difference, whereas that tube in the mic pre was a noticeable step from the the ECC81. I have to admit that my tube trials are easily affected by my hopes for a tube that I paid a lot for- not exactly scientific.
The SP8 was supplied from ARC with Siemens for both the AX and ATs and I found these to still be my first choice (along with Bugle Boys for the phono and the old triple mica black plate Sylvania 5751s in the line positions). Over time, I just keep returning to Siemens tubes for the small ones (except 6DJ8)- the Philips SQ branded Siemens-made triple mica 5814A became my favourite 12AU7 also.
As for the 12BH7, I bought a selection to try in the SP8 and the McIntosh MC240 which uses two:
GE- Brimar made black plate- NOS
RCA grey pl, D-getter, NOS
RCA grey pl, round gtr- NOS
RCA- blk pl, U-gtr - NOS 1949
Sylvania- grey pl, rnd gtr- NOS
GE- grey pl, rnd gtr- NOSI only compared the original ARC supplied GE with the GE branded Brimar black plate (this one is also seen rebranded as Mullard) and I couldn't hear any difference in the SP8. Someone had told me that the regular grey plate Sylvanias are a great and inexpensive "sleeper" -I'm looking forward to trying those out in the MC240 where the RCA black plate/U getters are my favourites. The MC240 when I bought it still had it's Macintosh branded 12BH7s and these were grey plate/round getter RCAs.
The manufacturers did often work out very good choices for their OEM tubes- while the great established makers wre still in business..
But- I still need to study!
Scruff, what did you end up running in your 8? What did you try out?
Cheers,
Bambi B
Hi Bambi - Thanks for the reply, I appreciate your opinions and hard work at this!Most all of my listening is CDs, I haven't rolled and don't plan to roll any in the phono section. Also for the sake of not putting everyone to sleep like I sometimes do - the tubes I refer to are all NOS or used and test almost new. The 8 that I settled on happen to be NOS and I made sure I have 3 more full sets stashed away!
In the phono section there are 2 ARC labeled 12AX7 that I think are Ei. Also 1 RCA 6922 - that I'm not sure of it's exact origin.
The most important to me is the line. There are 2 Siemens E83CC and 1 E188CC.
The power supply is 1 GE 6679 and 1 Sylvania 12BH7A.
In the line section for the 12AX7 positions, I tried the following: RCA 12AX7A and 7025. Some gray, some black.
Telefunken smooth plate labeled Fisher - 12AX7. Diamond on bottom.
Philips Holland - labeled Rogers - 7025. "delta" symbol visible.
Philips Holland, E83CC, "delta" symbol visible.
Philips JAN - 12AX7WA
Sino - 7025 - early version checked out and matched. These are the ones used by various companies and relabeled.
Siemens E83CCThe Siemens that sound best to me - the biggest complaint I had about all the others is they were a little harsh or sizzly near the high end. Particularly cymbals and piano notes. I didn't hear much I didn't like in the low end of any except they all seemed very little blurred. The Siemens didn't have the harsh high end, it did not blur the low end and it made a beautiful midrange. The midrange seemed a little more forward to me than all the others. If anyone told me that - I'd tell them it's baloney. I can't for the life of me figure how a tube can change image projection.
In the line 6DJ8 position, I tried Philips Miniwatt gold pin SQ 7308 and Siemens gold pin E188CC. I couldn't hear any difference, but stuck with the Siemens because I had spares for the future.
I should note here that I didn't try every combination possible. When I got the 12AX7 sounding good - I left the Siemens in and it might just be that the Philips SQ 7308 sounds better with a different 12AX7.
For the power supply I didn't hear any differences in the couple of tubes I tried, but ended up using a GE 6679 for the AT7 and Sylvania 12BH7A. I tried RCA 12AT7 and 6679 for the V7 and RCA black and gray for the V8. I couldn't hear any difference so again - I stuck with the ones I had spares for.
I don't see much if any talk here about the 6679 - from what I can find out it was designed for ham radio / military / broadcasting applications. The design characteristics are identical to the AT7 with one difference. It will operate like it's normal even with + or - 20% voltage variations. Although I don't have those conditions, thought it would be a good characteristic.
The final layout is V1, V2 = Ei 12AX7, V3 = RCA 6922, V4, V5 = Siemens E83CC, V6 = Siemens E188CC, V7 = GE 6679, V8 Sylvania 12BH7A.
Once I got the SP-8 to sound as good as my old SP-3 it was a huge burden lifted since during the process I was wondering if I did the right thing by getting the 8. I did make one mod to the 8 that was recommended and that was to replace the diodes in the two bridge sections. I'm not into mods, but can solder and read so thought I'd give it a try. Everything has settled in and I am happy as a clam in mud.
So there you have it. Yet another short story made long by the scruffy one! "Listen to the music!!"
Scruff,Thanks for your long and considered reply.
It is interesting to read of your choices for the 6DJ8 positions. My SP8 came from ARC with Philips JANs- never pleasing tubes for me. I tried Amperex Globe 'A-frame' 6DJ8s in the 8, but did not hear a difference and have left the Philips. What are those 6DJ8s doing?
The Siemens E83CC is indeed nice and that became my first choice for the phono 12AX7, although Amperex Bugle Boys will also do. I am sorry that I have so few of the ordinary ECC83 or E83CC around.
BTW, has anyone ever directly compared the Sovtek 12AX7LPS to its supposed Siemens original? I have even seen the Sovtek advertised as being based on the Siemens E83CC though certainly the LPS construction is without the E83CC's third mica. Would be nice if the Sovtek had some of the Siemens sound.
You're right that the 6679 is not often mentioned. Variants are strange things: I don't know how many people ever mention, for example any 6189 among their favourites either, but the 5814, 5963, and 6201 get noticed often.
As I mentioned, my belief in a difference for the 12AT7 may be out of hope rather than hearing. Perhaps it remains then only to have, like you did, a rugged, quiet tube there.I'm glad the SP8 is at least gradually coming up to your expectations. If ARC ever makes a commemorative reissue a la MacIntosh, the preamp choice should be the SP8. Mike Harvey, who later worked at ARC, said that ARC made a batch of 50 post-production SP8's for Asia, so perhaps it was already the only ARC 'reissue.'
Cheers,
Bambi B
Me again. In the owner's manual it says that the 6DJ8 are not normally critical although can introduce hum. I take that to mean they aren't used in a way that affects the sonic qualities we hear - unless they start to fail and we get hum. Based on that I wasn't overly concerned as to what kind I use, but since I ended up with 10K hours in V4 & 5, figured V6 should also be 10K design. I'm not hung up on anything right?I've not tried the Sovtek and for the time being don't plan to do any more rolling. Getting the SP-8 to sound good to me has not been the most fun.
Bambi if there's anything here you want to try, let me know and we'll figure out how to get pairs of them to you. No time frame. I know things take time and I eventually plan to sell or trade them. These do not test like new, but none below 1050 out of 1250 nominal on the Hikock 600A. All sections are close as they are tube to tube.
Telefunken smooth plate labeled Fisher - 12AX7. Diamond on bottom.
Philips Holland - labeled Rogers - 7025. "delta" symbol visible.
Philips Holland, E83CC, "delta" symbol visible.
Philips JAN - 12AX7WA
Sino - 7025 - early version checked out and matched. These are the ones used by various companies and relabeled.Thanks again for you input. Fran (aka - scruff)
Sarge,I forgot to mention the Philips 12AT7WA tubes. Will do good for a driver and they are cheap to boot.
CM
Hi Sarge,Here's my list:
Sylvania 6201 Gold Brand Gold Pins - Great tube
Mullard 6201 Gold Pins - tough
RCA 12AT7WA Command and RCA 12AT7 Black Plates - Durible
Telefunken 12AT7 - What can you say but great
Amperex BB 12AT7 - Very good but can get a little noisy but sound great.
I have not tried the GE Five Star but have some coming. Also have not tried the Ei 12AT7's but I will be getting some of these. I have tried their 12AX7 Elites and they are truly wonderful.
For the 5751 tubes, I have the late 1950's RCA with the white logo and black plates. Great tubes.
Hope this helps.
CM
Sarge, I've tried RCA's, Mullards, GE's, Telefunkens, Phillips, Raytheons and Sylvanias. As far as I'm concerned the Sylvania 6201 is the Rolls Royce of the 12AT7s. The Mullards were very good. Not much difference in the others strangely enough.
Ron
The 5751 is a 12AX7 not a 12AT7. They are different tubes and cannot be used interchangably.The 5751 is a lower gain 12AX7 and can be used most of the time in 12AX7 circuits.
Cut-Throat
I appreciate your taking the time to reply and guide me in the right direction.
-SK
I am not familiar with any current production types.I have a pair of what I believe to be late 50's TS with small black wing plates and large D type halo's that are fantastic in my Jolida 302. There is a review of this tube in the reviews area which echoes my perceptions. I don't know what it is about these tubes. I have tried several later versions of TS with grey plates and various halos but none of them are nearly as pleasing to me in this amp.
I also use Mullard ECC81 which has that sweet Mullard midrange but can be too sweet and muddy. I am intersted in hearing others thoughts on this. I have heard great things about the Sylvania gold brand 6201. I am planning on trying these soon.
For the more economical tube I have tried the Ei and EH. I liked the Ei a little better in the preamp. But the EH's are not bad but again I did like the Ei better. I haven't tried a Mullard but do have one on order. If you can use it in your set up I've heard good things about the Sylvania 6902 gold pins.
charles
"If you can use it in your set up I've heard good things about the Sylvania 6902 gold pins."
_________________________________________________________________
I think you mean the Slyvania 6201 gold pins.
Cut-Throat
Telefunken diamond is good: Mullard I do not know. Ei is also suprisingly good, although I have to replace every six months. I haven't tried the new extra special fine tested gold pin plated woopdedo 'EI Elites', but I would like too. perhaps they will last I don't know ; I do know the price is right.I have used the 12AT7 in the driver and input configuration, and like it. It must be run at about 8mA minimum in my humble opinion however.
Sincerely,
-3db
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