|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
216.222.111.167
I've got a fairly well matched/high testing pair of Hytron 12DW7's, but there's no indication of who the manufacturer may be. There's no etched code at the tube base, no numbers or anything between the pins, and none of the print seems to be rubbed off. It does have a sutured top with dark colored flashing from the getter. I'm suspecting they may be Russian, but with the information I just gave, does anyone have an idea who or where they originated from and are they a good sounding tube? (I have no application for them yet...it's on it's way).
Follow Ups:
Is that having seams at the top of glass? If so, two or four seams? Seamed top glass were manufactured in England & etched codes went away (I believe) sometime in the 1970s.Two very small (raised very little from glass) could be from Japan.
Seams on top are found on tons of tubes made by various Philips plants worldwide. Also on Tungsram, Ei and even some Telefunkens.Etched date codes did not go away in 1970s. Ones without date codes could be Matsushitas or BEL (often Bel India tubes had very faint date codes) or from some other plant.
I have IEC Mullard label tubes that have two seams on the glass and no etched codes. I assume English manufacture or English based tooling somewhere else. Like other tubes such as Amperex, the Amperex plants existed in Australia, Germany, US, Holland and perhaps a few other places.
NT
These have four seams on the top of the glass. Two are light and the other two are even lighter. I will try to post pictures.
lektrik,I'm not an expert in corporate juggling, but if your 12DW7s were made before 1952- or 1951 according to some, the tubes would have been made by Hytron- which was based in Salem, Mass. - and apparently a substantial tube manufacturer, until,..
In 1951 -or '52, Hytron was purchased by CBS and you'll see a lot of "CBS/Hytron" tubes from the mid-50's. I just bought 4- 5814As (fantastic 12AU7s) and these are labelled "CBS/Hytron". These 5814As were made in 1955 and 56, obviously after the merger. I think there are later tubes where the "Hytron" was dropped and they are labelled only "CBS", but I don't know how long CBS continued tube making- perhaps early 60's.
A 6CS6 I have is a plain "Hytron" and I assume made before 1952. The box reads "Hytron Radio and Electronics Corp., Salem, Mass" and "Manufacturers of Radio Tubes since 1921".
Cheers,
What makes me suspect that these tubes are not an actual Hytrons are: 1)sutured tops, 2)no date codes, 3)the Hytron name went out in mid 50's and I don't think 12dw7's were in production until late 50's at the earliest, 4)the boxes seem fairly new and have no extra print on the flaps, 5)halo getter...the tubes I have with the Hytron brand have bent rectangilar getters. I won't have the amp to try these out in for a week yet (Eico ST-70), but I'm still curious of who made them and do they sound good.
I just checked my tube case and looked at one of my Hytron JHY-5814 tubes from 1953 to see how they were built in comparison. You're right, those 5814's are one of the best sounding 12AU7 type tubes I've heard. I got them in a lot of military tubes and was blown away when I plugged them into my preamp. They sounded great right out of the box (which hadn't been touched since 1953).
Anyway, I bought these 12DW7's because I found the Mullards and Telefunkens to be a bit spendy. Hope they sound good...that's what counts.
lektrik,I apologize- I really avoided answering your actual question!
I only have two actual Hytron tubes- the rest are CBS/Hytron and none of these have the contstruction features you mention of the sutured top- which I associate with European tubes and given the type- not produced until after Hytron was gone- plus the halo getter that I don't see much before 1960.
Now, I'm curious too!
I don't know if the mid-50's CBS/Hytron 5814A is the same or based on the earlier Hytrons, but I've watched for four years until I had enough of those to use them everywhere- and I just received 4 a couple of days ago. I've only sepnt some time with them in McIntosh and my SCott 330D tuner, but as yuo say, the second you hear them you know there's something speacial. I'm debating whether to use one in the MPX unit of the McIntosh MR67 tuner where it may not have mimimal sonic value. I shouldn't go on about these though- the price will go up!
With your mystery tube, is it possible to post a picture? I'm sure someone here could recognize the maker by construction features.
Cheers,
I've tried all that I know how to post a picture, but can't get one to stick. Anyone know what to do?
When posting, notice the optional image & optional url spaces provided between message box & submit box; simply insert your pic or gallery www addy into that appropriate space & it will automaticaly accompany your message. Host your pic at a 24/7 web addy; your ISP may provide such gallery space or Google for such services (some at no cost). Email & pc files will not do as a 24/7 www addy. Also, read the asylum FAQ; see asylum supported html section & scroll to bottom for MUG FAQ if you desire to include multiple photos.
Hope this one works.....
That is what a 24/7 www addy means. Here is a link for one such picture web hosting service (see how easy; I merely inserted the site www addy into the optional url space & provided a title):
http://www.geocities.com/rxtxtubes/pa01007.htm
Sorry couldn't make it a direct link.
I may be mistaken but I believe that Sylvania may have taken over the Hytron facilities.Up untill the 70's at least Sylvania had plants in Danvers,Mass.I can't remeber ever seeing a Hytron plant but then I was in grade school in those days.For the record, the infamous Salem Witch Trials were actually held in Danvers.The site is pretty obscure and if you don't know where it is difficult to find it but it does have a marker, dating from the 1800's, letting you know you're in the right place.
Simply entering addy into the optional url space provided between message box & submit box provides a direct link.
This post is made possible by the generous support of people like you and our sponsors: