Correct, no adapter needed.Hi,
I understand that the 6j5 is a direct drop-in for the TRP but is it the same for the 6c5 i.e. no adapter needed?
Thanks.
I have been using the Gold Lion KT66 for most of the time as I just love the presentation. Have you tried the KT66 before the KT88's by any chance?My A3 TRP is SE with upgraded PS caps. The 6J5 family is very interesting so far - I picked up pairs of metal KenRad and GE that both proved to be 188-5, GE Kentucky, NOS tubes from late '40's and '51. Also pairs of early '50's metal based straight glass TS and Syl -gt's. the -gt's have a deeper stage, more detail and sound rounder/smoother to me. They are sweeter and also sound nice with the Majestic 80 rectifier. I did pick up a Cunningham (RCA) 380 that was defiitely darker, slower and almost syrupy with nuance lost to my ear. The Marconi U50/80 had more clarity than the Majestic, but leaned to the dry side and away from my warm fall pallet magic carpet wheelhouse.
The ST shaped euro versions look to be interesting, too - especially L63 variants, but I've not picked any up and put that family aside recently for the new issue Gold Lion KT88/nos Valvo AZ1 combos that are really floating my boat. I have a TFKN AZ1 mesh plate on the way to fine tune a bit, but overall am really loving the sound that's so big, natural and inviting with my VAC Phi Alpha integrated. And, it's nice to take a break from rolling and just listen when I have time while I'm diving into other commitments....probably through late Spring anyway.
I have the Westinghouse (Black) 6J5's, are these a drop in for the TRP? Forgive me if this has been answered.@christoph
Are you buying a Horizon? If so- Nice! I am not going to pretend to be the last word on how the Horizon functions but as far as a pentode goes the 6J5 is electrically the same so I would imagine it would work in that case.
Have you tried the 6J5 in your TRP yet? If not please do so- you’ll be surprised.
Yes sir, 6J5 tubes work in the TRP a treat, no adaptors required.I have the Westinghouse (Black) 6J5's, are these a drop in for the TRP? Forgive me if this has been answered.
Cheers RobertYes sir, 6J5 tubes work in the TRP a treat, no adaptors required.
Cheers,
Robert
Hello! I did try the KT66 - both GL and GEC - but some time ago. As I remember, they were midrange centric and sounded great with jazz, but less dynamic than the KT88. The 6J5 family has had my attention for months now and I'm particularly fond of KenRad 2c22/7193 and most recently STC Footscray 2c26a's - they are my favorite of the many I've listened to and I imagine I'll stick with them for a long while. A Valvo Vienna made AZ4 rectifier from the late '50's or early '60's is the perfect complement for me adding even for tonal density and more 3D character to the images. This combo has the depth, nuance, drive and involvement that sings in the way that leaves my brain behind while my heart rises. I can listen critically if I care to, but mostly I don't with these as I love being transported and transfixed like that.I have been using the Gold Lion KT66 for most of the time as I just love the presentation. Have you tried the KT66 before the KT88's by any chance?
Gret info thank youHello! I did try the KT66 - both GL and GEC - but some time ago. As I remember, they were midrange centric and sounded great with jazz, but less dynamic than the KT88. The 6J5 family has had my attention for months now and I'm particularly fond of KenRad 2c22/7193 and most recently STC Footscray 2c26a's - they are my favorite of the many I've listened to and I imagine I'll stick with them for a long while. A Valvo Vienna made AZ4 rectifier from the late '50's or early '60's is the perfect complement for me adding even for tonal density and more 3D character to the images. This combo has the depth, nuance, drive and involvement that sings in the way that leaves my brain behind while my heart rises. I can listen critically if I care to, but mostly I don't with these as I love being transported and transfixed like that.
Our 130 year old home is having an interior facelift with it's cracked plaster and sagging ceilings repaired and then my son and I will repaint them all...I imagine at least a month's worth of work. My withdrawal symptoms are starting to lessen a bit, but I'm really looking forward to getting the system set back up! I picked up a Mojo llluminati 3 LPS for my Pink Faun Bridge/Ultra clock and Modem/Router that will be great fun to check out, too.
Happy listening and enjoy the tunes!
While I haven’t run out and gotten any (at least yet) I’m rolling with you guys in spirit- I’ve been playing a quad of 7193’s all week!I seem to vaguely recall @budburma saying something about 6C26a tubes... I just wish he could be more clear if they are worth getting or not. Huh.
Took a swing at a quad. Just waiting for adaptors to be delivered - Canada Post is still sucking the life out of Canadians.
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Cheers,
Robert
Hey Groovy-Robert, That's wild and I love it!
On different note, I've racked up 480 hours on a pair of Natural Sound 6CA7-T. I'm really enjoying them. My previous favorite tube was the GL KT77. The 6CA7-Ts have a little more density and seem to be a little smoother from top to bottom while still maintaining some bite when need be.
Awesome, Robert. And the Arcturus are beautiful tubes, too. I'm curious how that ST shaped 80 compares to the Globes.Pushing the Triode Envelope
Ok, maybe not pushing any envelopes - more like scraping the bottom of the cheap triode barrel to see what might suffice. I blame @Designsfx for putting the idea in my head. He's probably having an evil laugh right about now.
The thought was to find old production single or dual indirectly triodes which:
1) Hadn't been tried in the TRP
2) Were "undiscovered" in terms of popular use in modern tube audio designs
3) Are readily available, or at least not rare
The truth is the above points came out of an overall desire to find tubes which have not been exploited and are therefore affordable to try. If successful there is a risk of initiating yet another "fashionable tube of the month" flavour and a purchase/sell frenzy. But I think the risk is relatively low since the tubes I settled on require more than just "adaptor of the month" to make work. In addition the closest directly usable tubes related to my choice here haven't exactly set the tube TRP community on fire...
Without further ado, enter the type 27 and type 56 indirectly heated single triode vacuum tubes:
Type 27
Type 56
I'll leave the historians to fill us in on the genealogy and the boffins to weigh in on the technical aspects. But briefly they are the ancestors of the 6J5G branch of the 6SN7 family tree and their filaments (heaters) require 2.5v, not the 6.2v that the TRP supplies. The pin-outs for these tubes are different than the 6J5, which plugs right into the TRP, but using adaptors also provides the opportunity to power the filaments externally by connecting them to an alternate power supply via a "break out" umbilical cord - one from each adaptor.
So, we need a 2.5v stable power supply that can provide 1.75a of current to each tube (type 27; the type 56 requires 1a per tube). In my case with a single-ended TRP that's two tubes, so 3.5a minimum, ideally 5a. And it would be nice if it didn't look like a dog's breakfast. I decided I would utilize a 12v 8a linear power supply I had on hand and build an intermediate "filament power supply" box containing off-the-shelf buck converters. The buck converters can accept 4-38vdc input and provide 1.25-36vdc output at 5a. They were cheap as chips and came two per package so I decided I would use them both and dedicate one per tube - that provides more than enough current capability.
I built a box from black acrylic and zebra wood. For the input cable I used an XLR connector and for the outputs I chose to install 5a rated barrel connectors. Then later I decided I wanted to use aviation connectors instead so wired them in parallel with the barrel connects, so I can use either. You'll note the switches on the front, one for each connector pair. I actually installed 4 buck transformers so that I can have a secondary alternate voltage at each output. The switches toggle between the 2.5v buck and the other buck I set at 3v. So, one switch for each side (channel, tube, whatever).
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The adaptors themselves were made for me by a user from another forum whose adaptors I have been happy with in the past. Beside adapting the grid, cathode, and anode pins to the type 27/56 tube sockets, they also have the two filament pins from the Lampi connected to nothing (the pins could also just be removed) and the two sockets feeding the tube filaments are connected to the cable that exits the side of the adaptor. I installed aviation connectors on these.
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I initially plugged everything in with the cover off the box and powered the box from my adjustable bench supply to monitor current draw and fine tune the voltage on the converters. That done I put the cover on and left things to cook for a while just to monitor heat. Two hours later and let's just say heat is a non-issue. I'm not given towards weird impulses, but if I were I could happily put my tongue on either the tube or the buck converter and barely register warmth.
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Time to see if this folly will burn down the Lampizator...
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Well, no sparks, no noise, no drama. Now to spend some quality time with tubes that were powering a radio when my grandfather was born...
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Cheers,
Robert
Thanks for reminding me to look up the dates on the STC tubes. That's one nice thing about true NOS - they generally have all lettering intact and you're at least able to read the markings when you begin the byzantine process of deciphering dates. Fortunately the UK system is well documented.Awesome, Robert. And the Arcturus are beautiful tubes, too. I'm curious how that ST shaped 80 compares to the Globes.
As an aside, all of my STC 2c26a's are dated MA (1/56) except one is LL (11/55). It looks they may have had a short run in Footscray. Or just a couple crates got left behind....
@WildPhydeaux. This seems a reliable source for British CV and Military date codes:Thanks for reminding me to look up the dates on the STC tubes. That's one nice thing about true NOS - they generally have all lettering intact and you're at least able to read the markings when you begin the byzantine process of deciphering dates. Fortunately the UK system is well documented.
I have an RCA globe 280 tube and really enjoy it. While looking for additional ones I found that Philco (Sylvania) 80 fairly cheap, so I took a punt. It's a really nice tube and I've been running it steadily now for about 6 months. I did swap back and forth a bit initially and the tubes are essentially equal in tone and neither bettered the other in soundstage or imaging. The only difference to my ear is that the Philco has a slightly more dynamic nature. It's very marginal but the leading edges of a dynamic swing seem a little sharper and more defined. To be honest I'm partly telling myself that the Philco is easier (less expensive) to replace than the globe, should it fail. Not sure why I'm "saving" the RCA. Silly really.
Cheers,
Robert
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