I lost a faithful tube tonight, a Westinghouse 12BH7. Served me faithfully in my ST-70 and the past 15 months in my M-125. She had a sweet tone about her, I shall miss her. 
TM
TM
+4
thompson12
corndog71
Bob Latino
10-E-C
8 posters
A Sad Ending
10-E-C- Posts : 267
Join date : 2014-02-12
Age : 70
Location : upper east tn
Bob Latino- Admin
- Posts : 3262
Join date : 2008-11-26
Location : Massachusetts
10-E-C wrote:I lost a faithful tube tonight, a Westinghouse 12BH7. Served me faithfully in my ST-70 and the past 15 months in my M-125. She had a sweet tone about her, I shall miss her.
TM
Sorry to hear that your Westinghouse 12BH7 bit the dust .. On a positive note > The nicest thing about the VTA amp kits is that there are MANY different 12AU7 type tubes that you can use as driver tubes. Any 12BH7 or 12BH7A or any 12AU7 type tube will work fine in these amps. This includes all the military/industrial versions of the 12AU7 > 5963, 5814, 6189 and the British Mullard CV4003. Up until the 1970's RCA, GE and Sylvania made millions of these (5963, 5814 and 6189) tubes for the USA military. They were also for industrial test gear and early computers that used tubes. If you look on Ebay or other places, and because the supply is still high, you will still see many of these advertised for sale at reasonable prices. Some are NOS and some are OS (old stock) that test as new.
I get asked a lot which is the "best" tube to use ? There is no best tube because ALL of them work well. There are, as you would expect, subtle differences in the sound of each tube. Depending on your associated music system gear some tubes may sound better than others. If you have a VTA ST-70 or ST-120 try changing out just the center (voltage amplifier) driver tube. If you have a pair of M-125's the front driver tube is the one to change out.
Bob
corndog71- Posts : 840
Join date : 2013-03-19
Location : It can get windy here
I just picked up a handful of OS 5963 tubes for a project. I tried a couple in my ST120 for fun. I was happily surprised by a GE labeled tube which had the tightest bass of the bunch. I paid less than $7 each!
10-E-C- Posts : 267
Join date : 2014-02-12
Age : 70
Location : upper east tn
Bob Latino wrote:10-E-C wrote:I lost a faithful tube tonight, a Westinghouse 12BH7. Served me faithfully in my ST-70 and the past 15 months in my M-125. She had a sweet tone about her, I shall miss her.
TM
Sorry to hear that your Westinghouse 12BH7 bit the dust .. On a positive note > The nicest thing about the VTA amp kits is that there are MANY different 12AU7 type tubes that you can use as driver tubes. Any 12BH7 or 12BH7A or any 12AU7 type tube will work fine in these amps. This includes all the military/industrial versions of the 12AU7 > 5963, 5814, 6189 and the British Mullard CV4003. Up until the 1970's RCA, GE and Sylvania made millions of these (5963, 5814 and 6189) tubes for the USA military. They were also for industrial test gear and early computers that used tubes. If you look on Ebay or other places, and because the supply is still high, you will still see many of these advertised for sale at reasonable prices. Some are NOS and some are OS (old stock) that test as new.
I get asked a lot which is the "best" tube to use ? There is no best tube because ALL of them work well. There are, as you would expect, subtle differences in the sound of each tube. Depending on your associated music system gear some tubes may sound better than others. If you have a VTA ST-70 or ST-120 try changing out just the center (voltage amplifier) driver tube. If you have a pair of M-125's the front driver tube is the one to change out.
Bob
Thanks for the info BOB, I have a stash of those tube types you have mention hoarded up.
I retired the other Westinghouse 12BH7 and put a pair of RCA 12BH7A Black Ladder Plates in my M125s I had picked up some time ago.
Another favorite tube I use is a JAN 5963 in the center position in my ST-70 with RCA clear tops in the outer position, to drive my old Klipschs.
The Westinghouse tubes were over 55 years old and I used them daily for over 3 years.
TM
Bob Latino- Admin
- Posts : 3262
Join date : 2008-11-26
Location : Massachusetts
Most of those "JAN" (Joint Army Navy) tubes were made by Sylvania but some were made by GE, Philips and possibly a few other manufacturers. ALL were well made and had to pass rigorous military tests. I find them to be better made, more reliable and even more important > usually better sounding than modern driver tubes from Russia, China or the Slovak Republic. If you get a tube set from me with your VTA amp kit, you will get USA made driver tubes ..
Bob
Bob
thompson12- Posts : 18
Join date : 2015-11-23
Age : 63
Location : Lehigh valley pa
Hi Bob, so your saying on the m125's you only have to change out the front driver tubes? What is the function of the rear tube? It will not affect the sound by changing only the front tube?
Mitch
Mitch
Bob Latino- Admin
- Posts : 3262
Join date : 2008-11-26
Location : Massachusetts
thompson12 wrote:Hi Bob, so your saying on the m125's you only have to change out the front driver tubes? What is the function of the rear tube? It will not affect the sound by changing only the front tube?
Mitch
Hi Mitch,
The front driver tube on the M-125 is the voltage amplifier tube and has a lot of influence on the sound of the amp. The rear tube is the phase splitter/inverter tube and has much less influence on the sound of the amp. Believe me I have tried to hear some differences by changing out the rear driver tube on my own M-125's. I found that as long as the rear tube is functionally good, the amp sounds pretty much the same with almost any (again - functionally good) 12AU7 type tube in there.
Bob
thompson12- Posts : 18
Join date : 2015-11-23
Age : 63
Location : Lehigh valley pa
Ok Thanks Bob, wow I can save some money on my tube rolling fun, I was buying matched quad sets, I bought 36 tubes from January till now. I wish I knew this before I could bought half the tubes.
I'm now looking for a set of 7316 amperex, nice to know I only need to get two of them there a little pricey
Mitch
I'm now looking for a set of 7316 amperex, nice to know I only need to get two of them there a little pricey
Mitch
Roy Mottram- Admin
- Posts : 1839
Join date : 2008-11-30
alot of people (myself included) also like the old RCA cleartops, alittle pricey for NOS, but cheap slightly used
thompson12- Posts : 18
Join date : 2015-11-23
Age : 63
Location : Lehigh valley pa
tubes4hifi wrote:alot of people (myself included) also like the old RCA cleartops, alittle pricey for NOS, but cheap slightly used
Clear tops where my main tubes till I got the amperex bugle boys, the clear tops sound really good but the bugle boys really made my tekton pendragons sing
Mitch
Kentley- Posts : 496
Join date : 2015-03-06
Age : 71
Location : Worcester, MA
For what it's worth, I've rolled over a dozen 12BH7As in my ST-120 center driver - RCA, Sylvania, GE, and others. Every single one is subtly different. My absolute fave, though, is an NIB/NOS TungSol. Rock-solid bass and shimmery top. Mids are round and present, as it seems all 12BH7s are. Quite a few currently on EekBay for around $40.
Next up for me is an Amperex Bugle Boy 12AU7.
BTW, I concur with Dr. Latino in his assessment of the two outer (splitter) drivers. Any functioning 12AU7 equivalent sounds identical there to me.
Next up for me is an Amperex Bugle Boy 12AU7.
BTW, I concur with Dr. Latino in his assessment of the two outer (splitter) drivers. Any functioning 12AU7 equivalent sounds identical there to me.
audiobill- Posts : 425
Join date : 2014-03-13
Location : Albany, NY
"Rock-solid bass and shimmery top. Mids are round and present."
Sounds like a fine vintage wine!!!!!
Sounds like a fine vintage wine!!!!!
Kentley- Posts : 496
Join date : 2015-03-06
Age : 71
Location : Worcester, MA
BUT - no chance of a hangover no matter how much you indulge in it!audiobill wrote:"Rock-solid bass and shimmery top. Mids are round and present."
Sounds like a fine vintage wine!!!!!
kaner- Posts : 93
Join date : 2011-09-20
I have the high gain / older version of the VTA st70 that uses 12AT7 tubes. Is there a list of compatible tubes that will work in my version?
Roy Mottram- Admin
- Posts : 1839
Join date : 2008-11-30
12AT7 replacements - almost any related type, ECC81, CV4024, 6201, 6060
Guest- Guest
Great info - I've been running the NOS GE/RCA BH7As - which are hard to come by - for the last 4+ years. Really happy with them as the new EH were really microphonic - and the one that was quiet - eventually bit the dust. The NOS tubes have lasted quite long.
|
|
|