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For your next tube roll, try using a pair of RCA Cleartops in the gain stage. These tubes have incredible air and openness, but are completely neutral, so use a warm tube as a follower. They are also very affordable.
The Brimar longplate will have similar sonics to your Mullard; warm, laid-back, with a liquid midrange.
Lowrider! Great minds think alike! I just bought 4 RCA Cleartops in NOS testing condition. They arrive Monday and I had a very similar thought. I'm glad you said this because it adds confidence that I'm on the right track in my experimenting. Read: I trust your opinion. I don't think you've ever led me astray.
I use 12au7 in my Primaluna Integrated Amp. I have tried several combos with the Mullard Reissue El34’s and GL KT77 Russian. I much prefer the KT77 sonic balance over the Mullard.
What I have found is that the Mullards have too much midrange forwardness and the KT77’s are much better balanced from top to bottom. More extension top to bottom,.the midrange is clearer and not forward.
For the Preamp section I like the combo of either the (2) Cifte or Tungsram in the Gain stage and the (2) NEC/Mullard in the first Driver Stage. The second driver stage I use the stock (2)12au7 Chinese tube.
Aniwolfe I have the NEC/Mullard in the 1st driver stage along with the stock PL tubes in the gain stages along with the KT77 at the moment. I am finding its too energetic in the upper mids so I am going to roll in something else in the very back or rearmost 2 slots. I agree with your assessment on the KT77s.
I installed 2 NOS Cleartops followed by 4 NOS Mullard CV4003s. I'm using my reissue Mullard EL34s in the power stage.
This is a pretty nice mix. The RCA Cleartops sound pretty rich and bombastic in the bass. I'd swear they have a ton of punch--similar to solid state in the low end.
I think the Mullard CV4003s are too dark to run them across the entire preamp board with 6 tubes.
The Cleartops have a good bit of energy for sure. With this mix, I really like them. Maybe I'll swap in 4 just to get a good look at making an assessment of the tube. My experience with 50s RCA tubes has been positive. They all seem to have a tight, strong sound that is forward.
The mixing of preamp tubes seems to get me closer to where I want to be.
In my Primaluna Dialogue Premium the EL34 Mullard reissue are brighter and more forward than the stock PL power tubes but lacking in bass. The Mullard CV 4003 brought back some bass but finding the CV 4003 definitely darken up the sound. Maybe I should try some RCA Cleartops. Has anyone compared them to the Amperex (Holland) 7316? The 7316 has some energy but very detailed and expensive :(
JB this is becoming an interesting experiment ($$$) and I am enjoying reading about your findings.
It is an expensive experiment. So far on preamp tubes, I've collected RCA D getter black plates, RCA Cleartops, Mullard CV4003, 70s Amperex/Mullards, GE 5 stars, Baldwin, Ciftes, and a couple others. Fortunately, this has not been wasteful because all the tubes are very good and listenable. They will eventually get use. And, I do think there's something to be said for buying a $5k amp and not being pennywise pound foolish.
Lowrider57, I have not tried those Bugle Boys. They are a bit pricey, but I'll get them on my short list. Maybe a birthday or father's day gift.
Can I ask what Pre-Amp/Power Amp you are using? I just had an interesting experience tube rolling. Rolled in 3 Psvane 12AX7-11 into my Vincent SA-T8. Wow! What an improvement. Sounded great with both my Vincent s/s SP-998 Mono Blocks & upgraded s/s Benchmark Plexus Power Amp. Immediately ordered a quad of Psvane 12AU7-11 to replace the "no-name" Chinese 12AU7's in the SA-T8. I switched on the Benchmark Power Amp. Yuk, way, way too bright sounding. I switched back in the Vincent Mono Blacks. Voila! Absolute magic! Dynamics, depth, soundstage etc. just exploded.
So, initially putting the 3 Psvane 12AX7's in the SA-T8 and both Power Amp & Mono Blocks sound really good. Then roll in 4 Psvane 12AU7's as well, (so all 7 tubes in Pre. are now Psvane) and when connect up Power Amp sound not so good but sound when Mono Blocks connected, awesome. Difference is staggering. Must be incredible synergy and non-synergy going on. I suppose some more experienced tube rollers would be able to relate some similar expriences.
Thanks jb. Always interesting to know what equipment people are using, as different tubes wiil give different results in certain equipment.
As for Vincent products I have half a dozen. All are good to great bang for buck. Their top line SA-T8 Pre. and SP-998 Mono Blocks blow many mega buck products to the shizenhausen, they are that good.
ECC82 /12AU7 Mullard longplates, square getter, 1950s vintage, Great Britain.
Found on Brent Jessee site...
These are all the older long narrow plate version, with the rare early SQUARE top getter, with the 1950s date code. These are incredible tubes with a fine soundstage, clean top end with a touch of midrange warmth. Rare.
The different types of Mullards and year produced results in different sonic signatures. CV491 military and CV4003 are warm, textured, and laid-back. The ECC82 square getter is a more open tube, so is the ECC82/12AU7 Mullard longplates, halo getter.
Mullard reissues have nothing in common sonically with NOS Mullards. The Mullard name and trademark have been acquired by the New Sensor Corporation (Russian factory); same comany that makes new Tung-Sol, Sovtek, Electro-Harmonix.
(I have never tried Cifties).
JB I agree they would be too much of a good thing. Right now I am sticking with the stock Primaluna in the rear 4 slots and playing around with the front 2. Last night I put the Gold Lion KT88 back in and while they aren't quite broken in, they have some nice qualities. However, they don't draw me "into" the music like the KT77 or EL34 power tubes or at least not so far. Mood and awareness also can affect our ears so I am being patient and having fun playing around with tubes.