Refreshing my RTA 15TLs

bcwsrt

So, I can't say that I've experienced the changes over time that I've read about here. Not that that's a bad thing, though. This capacitor/resistor/binding post upgrade started out surpassing my expectations and has stayed remarkably the same way over the past 125+ hours of burn-in. I did roll the stock JJ 12AU7 back into the center position of my CM3 today after @charley96 was over yesterday and questioned the bass response from the last time he'd been here. To my surprise, that did fill the bass out more, without sacrificing the midrange presence that the RCA 5814s (Ivan's recommendation) in the outboard 12AU7 positions provide. Does this combo jive better with the new crossovers or was the bass lacking all this time and I just never noticed it, who knows? Never hurts to get others' opinions and challenge your status quo.

Since the day-to-day has been so consistent, I've disconnected the Denon from 24/7 white noise duty and will just continue to enjoy as per normal from now on. Without a doubt, there is more punch and clarity, the soundstage is larger, the imaging is more accurate and stable and vocals are more lifelike and truer than before the cap and resistor upgrade.

Shoutout one more time to Ivan for breathing new life back into these 30 year-old antiques. Thanks, man!

EndersShadow

Oh man… you met @pitdogg2 …… I’m shocked you are not scarred for life.

I know I am

pitdogg2

EndersShadow wrote: »

Oh man… you met @pitdogg2 …… I’m shocked you are not scarred for life.

I know I am

😂😂😂

pitdogg2

There is a ton of decently priced 12au7's out there. How many does that piece of gear take? Are there other tubes there as well?

msg

I've only seen photos, but pretty sure I'd be beaten up for lunch money if ever we met in real life.
My shoes, prob'ly, as well.

Ivan was one of those kids who hung out in the woods just off school grounds until the bell rang.
So was @txcoastal1

pitdogg2

I hang your shoes from the overhead wires Scott!

bcwsrt

pitdogg2 wrote: »

There is a ton of decently priced 12au7's out there. How many does that piece of gear take? Are there other tubes there as well?

There are three 12AU7s and two 12AX7s.

They guys on Steve Hoffman say Amperex and Telefunken are the way to go for the CM3, so I have eBay searches setup for those. The ones that are popping up are fooking pricey, though.

I'm liking those 5814 triple mica black plates in two of the three 12AU7 slots. Maybe I just need to find another single one to complete the trio.

Obviously open to any 12AX7 recommendations!

pitdogg2

Amperex and Telefunken

Some of the most expensive tubes on the market. Some can go for hundreds.
12bz7 could be an option for the 12ax7. GE made all of them no matter the name on the tube. I prefer early 40's to 50's black plates.

Here's some
https://www.ebay.com/itm/266105556624
Keep your eyes on them (12bz7) they come and go. My last pair 1944 I paid less than $30 shipped to me. Cheap enough to try, they are a good substitute for the 12ax.

Keep an eye on this guys stuff bought good things from him multiple times.
https://www.ebay.com/itm/285125938680

audioluvr

These are also really good, inexpensive 12AU7's and the seller is legit.

https://www.ebay.com/itm/394464956189?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=QPafZ8pRSAG&sssrc=2349624&ssuid=HCBfXk2rTBy&var=&widget_ver=artemis&media=SMS

bcwsrt

A lot of the RCA stuff has gone nuts, too.

12AX7 choices in general, let alone economical ones, are a little slim on eBay (and the other typical sources like Brent Jesse, Upscale Audio, etc.) at the moment, unless sourced from Chyna. I'd have to check with Rogue about using the 12BZ7 as a substitute.

The "platinum plus" version of those Raytheon AUs are on their way. USA tubes for my USA amp and speakers, love it. 🇺🇸

Thanks for the feedback, gents!

bcwsrt

I just wanted to follow-up on the 12BZ7 convo above before I forgot, just to close the loop on it. Nick at Rogue responded to me promptly yesterday AM. For me, it’s a no-go since I’m still under warranty. Not saying it wouldn’t still be fine, but his response didn’t give me the warm fuzzies. I didn’t see any available on the common sites at the moment, so it’s not like I could’ve jumped on anything anyway. Was a good thought, though! Gotta think outside the box in these crazy times.

bcwsrt

audioluvr wrote: »

These are also really good, inexpensive 12AU7's and the seller is legit.

https://www.ebay.com/itm/394464956189?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=QPafZ8pRSAG&sssrc=2349624&ssuid=HCBfXk2rTBy&var=&widget_ver=artemis&media=SMS

Well, you gents do not mess around when you recommend tubes on here. Very smooth and natural-sounding tube! Well-suited for contemporary jazz ... horns sound super-airy and full of lifelike timbre. Lots of mid-low midrange punch, too. Some earlier Doobie Bros. on vinyl sounds crazy-revealing and better than I think I've ever heard it. Those acoustic guitars on "Black Water" and the beat on "It Keeps You Runnin'" ... so nice!

I need to experiment some more with various combinations of the stock JJs, the RCA 5814s that Ivan recommended and these, but with one of these matched pair in the center and those 5814s in the outside spots, I'm finding little to complain about at the moment.

This forum is great!

pitdogg2

The Raytheon black plates are sublime. If you can get ahold of any of the Raytheon windmill getters those take it up a step. The black plate are the better of the two but the gray plated mid sixties are no slouch either. They are not cheap!
Look into some Tung-Sol's the mid fifties to early sixties 12au, 12ax and 5814, 5751's are worth having in your stable. Stay away from all the Russian made Tung-Sol made signal tubes.
Honestly it's hard to go wrong with any of the big three that were used by the Organ makers. They seemed to have been screened much better. Raytheon, Westinghouse and RCA, The Sylvania's can go either way.

dromunds

Stay away from JJ’s.

bcwsrt

The Tung-Sol recommendation opened up some 12AX7 options I hadn’t seen earlier. 👍

audioluvr

bcwsrt wrote: »

The Tung-Sol recommendation opened up some 12AX7 options I hadn’t seen earlier. 👍

How many do you need? I think I have a pair I can donate to your journey. PM me

audioluvr

Here's what I have in the not needed pile. Maybe someone here can shed light on their provenance. Can't guarantee the boxes match the contents.

pitdogg2

More pictures of the labeling and plate construction. The group of numbers in the one picture make no sense to .e ATM. I'm fairly certain that it wasn't made in 1992 (92 12) 🤓

bcwsrt

92nd day of 2012? 🤷‍♂️😁

pitdogg2

bcwsrt wrote: »

92nd day of 2012? 🤷‍♂️😁

Mmmm no😬

audioluvr

Looks like made in England. I can also see in crazy faint letters:
2A1
10C

pitdogg2

Chances are they were made in Japan by Matsushita who made tubes on Mullard equipment.
On the other hand George Westinghouse also had made deals with N. Tesla and they could be Tungsram, made in Hungary or even original Yugo Ei tubes.
Once again better pictures of the tubes(not super close ups) simple close shots of all sides to actually see color of plates and better shots of the plates construction.
FACT:
Lots of tubes had "made in England" stenciled on them, those that were made behind the Iron curtain to bypass trade restrictions.

RCA and also GE made tubes branded Westinghouse

bcwsrt

Did Westinghouse actually manufacture any of their own tubes? I did some research on what these could be yesterday morning and it sounds like a lot of Westinghouse is rebranded and may not always be reputable RCA, GE, Raytheon, etc.

Making Rob work hard here! 😝 Hopefully, he doesn’t mind. It’s all interesting!

pitdogg2

bcwsrt wrote: »

Did Westinghouse actually manufacture any of their own tubes?

Yes I have many Westinghouse made tubes. Here is a pair of 12au7. The dots around the tube number(which may or may not have a circle around it) is one dead give away.
Most will have a horseshoe getter with either two bars or a foil strip across the open end of the horseshoe. The plates will be carbon colored, not black yet not gray either. Hopefully you can see.

audioluvr

Ivan, they're a flat dark grey, short smooth plate halo getter. It's dark and dingy today otherwise I'd get better pics.

pitdogg2

Short smooth plate no ladder bars, pretty sure those are not true Westinghouse. Two manufacturers come to mind quickly. One would be Brimar. They other could be Telefunken or a company that used Telefunken tooling. Yugo Ei would be one of those.

msg

Which one of these bulbs would fit my lava lamp?

pitdogg2

msg wrote: »

Which one of these bulbs would fit my lava lamp?

You'll need an erectifier.....

bcwsrt

Getting ready to do @xschop ’s tweeter plates and BH5 to complete these.

Ivan sent our plates off for black anodizing, but they came back a little iffy-looking. There were what looked like some fisheyes or water spots in the finish and some scratches from some evidently careless post-process handling.

It is what it is and we both agreed it wasn’t bad enough to send back since we keep our grills on practically all the time, but I still thought I’d see what I could do to improve them. I wanted to keep the bare anodized look, so didn’t want to cover them up with paint. These Adam’s automotive products accomplished what I was after. Didn’t do much for the scratches, but the funky-looking spots are gone.

I used one coat of the trim restorer and two coats of the graphene coating. Should last a good, long while since they won’t be seeing too many car washes. 😝

Before:


Trim restorer after application and after curing:



Coating:

pitdogg2

Damn, I'm impressed !