For ECC83, I like Phillips Delta codes from Harleen.
For ECC82 and 91, I like Pope Holland, Amperex/BugleBoy, Valco and certain Tungsram and vintage TESLA. NEC is undisputed king of the small signal dual triodes!
Down the line are certain Lorenz, Marconi, Ei, Mazda and Siemens. Cant recall the French brand and then Brimar and after Mullard and Telefunken. For E84L, the German brands Siemens and RKD are nice.
Have you ever wondered if we could somehow remove the crud on the tube connector pins if there would be a major increase in SQ? Phil, I say this, as looking at your photo really shows the typical pin condition of so many of these NOS tubes.
I have never cleaned or removed the varnish on these pins, but I reckon that might be beneficial....what do you think?
Have you ever wondered if we could somehow remove the crud on the tube connector pins if there would be a major increase in SQ? Phil, I say this, as looking at your photo really shows the typical pin condition of so many of these NOS tubes.
I have never cleaned or removed the varnish on these pins, but I reckon that might be beneficial....what do you think?
The only thing I ever dared to do was to use alcohol on cotton swabs to clean the pins. Even then I hear little Improvements after the cleaning. Some go as far as using a needle file to remove the crud. That might clean the pins but could make the pins thinner eventually. I wouldn't do it.
The only thing I ever dared to do was to use alcohol on cotton swabs to clean the pins. Even then I hear little Improvements after the cleaning. Some go as far as using a needle file to remove the crud. That might clean the pins but could make the pins thinner eventually. I wouldn't do it.
I agree with you, which is why I have left well enough alone. However, I suspect that if there was a safe and easy option to remove the crud, then it may be an ear opener, SQ wise...that would be my suspicion given the improvement to be had with clean contacts elsewhere.
Sorry for being OT here but could you elaborate on those mods? Just replace the old parts for newer and nicer ones of the same values?
I have a pair of Acoustats Spectra 22 that I already love as they are...
Wow, when I clicked on your location, I realized that you are only 30 minutes away from me
What a coincidence
Hi Christoph
Nice to hear from a fellow Spectra22 owner!
I had my interfaces rebuilt by Dan Santoni (Blackdog) in Hamilton. He basically replaced all the parts and wiring with modern parts. He also increased the bias current to the panels (almost all 35 year old Acoustats now have low bias which really hurts the sound quality) and equalized the bias for each speaker (which eliminated an annoying channel imbalance I had). Higher bias makes the speakers more efficient and easier to drive (with tubes). Also new three prong power cords.
I had mine done several years ago so I don’t want to quote you a price, but it was well under a thousand Canadian. Some of the best money I ever spent in this hobby! DO IT! You will be amazed by the improvement!
Next up for me is new wood frames alla Magnastand. I just have to find someone who can do it I am useless with tools.
First time to see a 45? D-getter Telefunken tube which was actually made by Siemens Halske based on the =2 k6R date code at the bottom. Very lush and warm sounding 64-year-old tube.
As to 6SN7s, I tested about 15 tubes from 7 manufacturers. Those I despised were Soviet Russia tubes, also relabeled UK and Counterpoint-thin and flat sounding. GEs from most eras sounded grainy and just okay. Best were Raytheon, Ken-Rad and RCA (all eras for RCA were at least very good) and Sylvanias. Note that the first three sounded full, rich, warm and dynamic (especially the 40s and 50s tubes) while the Sylvania chrome dome (50s) was excellent but diametrically different in tonal balance (very open and forward). I recommend mostly earlier varieties and any RCA. I may try Sophia Electric versions in the future.
As to 12AU7s, I found the RCA clear-top fit best with several pre-amps. I tried at least a dozen 12AX7s and preferred either very early D getter or large O getter Sylvanias or the really neutral and extended frequency range of the Mullard CV 4004 which is tonally totally different from the very warm typical Mullard.
I've been using tube gear for over 50 years. My current preamp and phono preamp use 6 and 8 subminiature tubes, respectively, which have a reported lifespan of 100,000 hours, no vibration problem and high gain. In use over 10,000 hours and sound just like new.
Much of the current equipment made today is tuned using common modern/available tubes by the manufacturer. Changing the tubes don't always result in better sound. Then there are the manufacturers who choose to use obscure NOS tubes such as Allnic Audio.
Have set of these ECC82CV4003 Mullard Box Anodes and matching same vintage Brimars --Drivers in my Amp
Superb tubes all round
BruceD View attachment 72107
I love the 1950's Brimar boxplates. I have the CV4003 & CV4004.
Also the Mullard CV4004, but now using a early Mullard ECC83 long plate square getter in one of my amps.
Some of my favourite non-Sylvania 6SN7s.
National Union black glass, Raytheon 6SN7WGT, RCA 5692 red base, Russian 1578 hole plates, Tung Sol “mouse ears”, RCA VT-231 grey glass
I agree with you, which is why I have left well enough alone. However, I suspect that if there was a safe and easy option to remove the crud, then it may be an ear opener, SQ wise...that would be my suspicion given the improvement to be had with clean contacts elsewhere.
I use a small, fine wire brush gently on the pins , then scrub with Q-tip dipped in 99% iso alcohol. Keep cleaning until the Q-tip no longer turns black. It will probably take at least both sides of the Q-tip. You would be amazed how much crud comes off!
Now you have a clean tube, and they do sound better than they did dirty.
I have experimented in the past with contact enhancer on tube pins, namely Walker Extreme SST, and the results are a clearly audible improvement. However, I have never been entirely comfortable doing this, and it is difficult to clean out of small tube sockets, and a good cleaning of the pins gets you most of the improvement anyways.
Some of my favourite non-Sylvania 6SN7s.
National Union black glass, Raytheon 6SN7WGT, RCA 5692 red base, Russian 1578 hole plates, Tung Sol “mouse ears”, RCA VT-231 grey glass
The Melz 1578 OTK hole plates have out of this world sonics; wide and deep soundstage, excellent low-end extension, smooth highs, and a holographic yet realistic presentation. Mine are from 1980 and have some noise, specifically they don't provide a black background.
I've had several failures with these tubes after burn-in. I purchased 3 pair from a Russian dealer who was recommended to me and 3 tubes started crackling. I found out that by 1980, quality control was poor and the pins had loose connections with the internals.
@Mendel
Have you had any issues with your 1578's and do you know what year they are?
(We may have discussed this before, but memory fades)
Have set of these ECC82CV4003 Mullard Box Anodes and matching same vintage Brimars --Drivers in my Amp
Superb tubes all round
BruceD View attachment 72107
