It is currently Mon Mar 16, 2020 7:46 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 143 posts ]  Go to page Previous  1 ... 6, 7, 8, 9, 10  Next
Go to page Previous  1 ... 6, 7, 8, 9, 10  Next
Author Message
Post subject: Re: 12AX7/7025 Tubes
Posted: Thu Jul 17, 2014 6:57 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Thu Feb 19, 2009 8:33 pm
Posts: 457
Location: Bushnell, FL
yomammaaho wrote:
That 58 short plate/square getter has really pleased me in my V1 slot. Very strong.
But I could shoot myself for selling 20 plus long shiny black plate Raytheon's recently. Only kept 1 for myself....like a dumb $@!&.
I agree! On all points, should have kept them. :lol:

_________________
Charlie P 5E3 Build 6-14
2x12 cab Build 16, 5e3 Built 3-4-16
6G3 Head Build 3,3,18
Fend HSS Am DLX Strat 08
Fend MIM Telebot Dlx 11 Tronical Tuner
Fend SupSonic 60 2010
Gibson Robot 08, Gib. Faded Ch LP 07
Gret. G5420 16, Peavey VK112 08,


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: 12AX7/7025 Tubes
Posted: Sat Jul 19, 2014 6:58 am
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
Keep eye out. Baldwin pulls (9-pin minis) are often Raytheon made tubes.


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sat Jul 19, 2014 9:09 am
Offline
Amateur
Amateur

Joined: Thu Apr 11, 2013 2:55 pm
Posts: 183
Yep. That's exactly where they're from.
Ya know....for long plate tubes, I couldn't find a one that was microphonic in V1. Makes me wonder why it seems to be rocket science to produce a new production long plate ax7 that's quiet.
Would think simply a tighter fitting mica would resolve.


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sun Jul 20, 2014 7:18 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Sat May 22, 2010 10:53 pm
Posts: 1467
Location: deep down in Florida...
yomammaaho wrote:
Makes me wonder why it seems to be rocket science to produce a new production long plate ax7 that's quiet.


If you haven't read my reviews of the Gold Lion B759/12AX7, that tube is new production long plate and the ones I tested were quiet and not microphonic, compared to something like the Mullard RI 12AX7 LP.


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sun Jul 20, 2014 11:13 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
cedarblues wrote:
If you haven't read my reviews of the Gold Lion B759/12AX7, that tube is new production long plate and the ones I tested were quiet and not microphonic, compared to something like the Mullard RI 12AX7 LP.


+1

I like what I'm hearing thus far from the GL as first/second gain stage pre-amp tube.

Is it blackplate RCA?

No.

But it isn't sixty bucks either.

:mrgreen:

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Tue Aug 28, 2018 9:28 pm
Offline
Professional Musician
Professional Musician

Joined: Tue Nov 27, 2012 6:56 am
Posts: 1677
Location: Coastal Bend, Tx.
So I dug this old post up in a search for a question I have about TFK tubes. I thought it was a good read all the way through and w/ not much going on in the forum lately, why not.

But I didn't find an answer so if anyone knows lemme know. My guess would be a production run number.

What are the two pairs/sets of identical 3 digit numbers found on the tops of some TFK tubes?


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Wed Aug 29, 2018 7:17 am
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
They are date and manufacturer site codes. Here's the link:

http://www.audiotubes.com/teledate.htm


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Wed Aug 29, 2018 7:25 am
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
BTW... I scrounged-up an NOS pair of mil spec, black plate Raytheon 12AX7 for my new phono pre-amp. This era Raytheon (late 1950s - early 1960s), are just as good tone-wise and length of consistent life, as any TFK, Philips (Mullard), or Valvo ECC83 of that era. IMHO. Your mileage will not vary.

They really made good tubes, in those days.

:mrgreen:

Image


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Wed Aug 29, 2018 12:35 pm
Offline
Professional Musician
Professional Musician

Joined: Tue Nov 27, 2012 6:56 am
Posts: 1677
Location: Coastal Bend, Tx.
Very nice Beemer!
Only reason I ask is there are a bunch in a recent grab bag purchase from the evil bay and still haven't ever seen an explanation anywhere. I'm good on the date codes but appreciate the time to post the link. I bid only seeing a couple labels exposed 5ar4 and 4-12ax7a. The 5ar4 turned out poorly(no vacuum Mullard) but the 12ax7's turned out to be TFK smooth plates and there were a half dozen 7189's along w/ several other non guitar tubes that may come in handy one day.
Here are some pics:
Image
Image
These are the numbers I was asking about, sorry not the best focus.
Image
And these are the other TFK, mullard, etc that weren't US made.
Image
There was about 100 or so tubes in the lot mostly in Motorola, GE, RCA or Realistic boxes. Surprisingly, tubes mostly matched what was on the boxes.
Not bad for the cost of a case of beer :D


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Fri Aug 31, 2018 3:53 am
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
Eric, nice haul of TFK ECC83s. Too bad that GZ34 is bad. :(


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Fri Aug 31, 2018 5:32 am
Offline
Professional Musician
Professional Musician

Joined: Tue Nov 27, 2012 6:56 am
Posts: 1677
Location: Coastal Bend, Tx.
That was the 1st box I opened, since basically my bid was a best offer I had low expectations. The tube was a double O getter F31 from Blackburn. This stash was from a radio guy in Washigton, the rest of the tubes look pretty much like any old tube caddy you might find emptied into a box. Of the tubes I can use in my amps I did really well this time.
The 6-7189/el84's (I don't have an amp for these) 2 RCA, 2GE and 2 RFT.
All my hi-fi gear is SS and I dont have any older radios or a transmitters so the rest of the tubes will just sit unless I go to a swap meet or buy something that needs them.


Also looking through my stash I found a couple ax7's that have the "medical symbol" on them and say electronics for medical use. One from Holland and one from England, gotta check them out on tubemonger to figure what type they are but just a quick scan and none had the symbols. Neither has a colored tip or brand label, so it will be a construction comparison. They both look like Mullard construction and one has a B0K3 code. Here they are.
Image


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sat Sep 01, 2018 9:25 pm
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
Any Philips brand (aka Mullard or Miniwatt) of this era is excellent. As long as they test well. So, you got good buy.

Medical grade is equivalent to mil spec or commercial grade. Usually, for high test and not necessarily good tone or quietness.


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sun Sep 02, 2018 8:12 am
Offline
Professional Musician
Professional Musician

Joined: Tue Nov 27, 2012 6:56 am
Posts: 1677
Location: Coastal Bend, Tx.
I ran all the TFK's and the two Medical tubes through the Bronco in V1. One of the Medicals was microphonic but all the rest were very quiet.
Tonally all the TFK were equal, well balanced with a slight favor towards the high and low frequencies. A tad brighter than my liking when played clean. The breakup range was relatively higher than many tubes I've tried and the tone wasn't as well balanced but that may have been the speaker not being as capable. The medical tube was as clear as the TFK but had better midrange thickness and sounded slightly better when pushed hard, but that may have been due to the speakers performance range also.
I still prefer an RCA in V1, at least in the Bronco.
I'll give them another sound test in the V1 & V4 slots of the DRRI and SR, just to find a better slot for them. I may try them in PI also.
I didn't try them w/ a bucker fitted guitar, so I will with the next test. I think they'll be better in V1 with a bucker, since they don't tend to breakup to early.
BrentJesse was the only place I found that had a reference to the medical symbol and use label; he calls them Amperex. I think all the major European makers of the 60's are all pretty close to the same design/construction specs and couldn't find any literature to nail down confirmation of the markings. The 63 Amperex tube catalog didn't mention them.

No doubt the best 27.50 I've spent in my short tube life.
Appreciate your input


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Sun Sep 02, 2018 9:45 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26415
Location: Tombstone Territory
sfceric64 wrote:
The 63 Amperex tube catalog didn't mention them.


Unless you have a copy of Amperex's industrial/commercial product catalog, you'll likely not find much on their medically-certified vacuum tubes.

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: 12AX7/7025 Tubes
Posted: Tue Sep 04, 2018 5:52 am
Offline
Professional Musician
Professional Musician

Joined: Tue Nov 27, 2012 6:56 am
Posts: 1677
Location: Coastal Bend, Tx.
Couldn't find that rare gem on the net.
If I were to believe the internet, there are many that say "electronics for medicine" is a NY company that sourced tubes for medical equipment (EKG/ECG) from Phillips/Amperex, who had there Holland plant fill the orders using Mullard components. All good, I know what they sound like.
Thanks Roger.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 143 posts ]  Go to page Previous  1 ... 6, 7, 8, 9, 10  Next
Go to page Previous  1 ... 6, 7, 8, 9, 10  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: