[rydenfan]

Well, last night I swapped out my current fave Tung Sol 5U4G for my newest addition, a Valvo/Mullard early 50's vintage 5AR4/GZ34 metal base

and my tube board fuse blew.  Hmmm....luckily it was the stock fuse, not the $39 HiFi Tuning one I was about to install later this week.  I've got to go to Rat Shack and get more to try again and determine if this fairly $$ used Ebay tube is bad....guess I could go to a local tv repair-type shop and use their tube tester huh?  Dunno about any of these things, really.

Well, I put the Tung Sol back in and replaced the fuse with the only one I had, the HiFi Tuning one, temporarily.  While I was in there I noticed the main ac fuse, on the board nearest the IEC, is marked on the pc board as 500mA slo blo...but the recommendations here were 1A fast blo, so I removed the fuse and sure enough it is indeed a 500mA slo.  Are these interchangeable, one being rated 2x over the other and fast not slo?  Thx

Ted, I have tried out a few different 5AR4's and had no issues so I wonder if it is that tube? I am glad to hear with was not your HiFi fuse. I can safely say that this porder I placed will be the last time the Cable Company ever sees business from me. They are not very good at telling the truth. Anyway, that is very surprising at the main ac fuse. I hope Dan will respond to us as i already have a HiFi fuse for it (1A fast blow) but have not installed it yet as I am waiting till I get my 3a ones (if I ever do  )

[rpf]

David, I'm sorry to hear you've had problems with the Cable Company. I've dealt with Paul there for several years and it's been nothing but a pleasure. They can be a little slow at times (and even forgetful over minor things when they're really busy) but they've always been generous with loans, excellent with information and good with pricing. Maybe it was your sales person? 

Let me know when you're ready to try the High Wycombe GZ37.

[rydenfan]

David, I'm sorry to hear you've had problems with the Cable Company. I've dealt with Paul there for several years and it's been nothing but a pleasure. They can be a little slow at times (and even forgetful over minor things when they're really busy) but they've always been generous with loans, excellent with information and good with pricing. Maybe it was your sales person? 

I know others seem to have luck but i guess just not me. Each time i order something i always say it is the last time 

Let me know when you're ready to try the High Wycombe GZ37.

I was born ready! 

[ted_b]

Joe @ The Cable Company is a gentleman and a scholar..and great to do business with.  If I have a borrow issue my next one is free, my orders arrive in like 2 days (hifi fuses came in 2 days; special orders like AR-77 and some Wattgates took a little longer) and he's knowledgeable and has pointed me in less expensive or less traveled paths, almost always with a success.  It helps that they are one state over.

[rydenfan]

I had a guy named John who did not tell me 2 of the 3 three fuses I ordered were on back-order. He then told the lady Chris that he had spoken to me about this and that I told him to charge me for everything anyway, which was a total lie  I have then left three messages this week to try and find out the status of the fuses I ordered a few weeks ago and I have yet to get a call back. Very, very shady and unethical. Sorry for going OT and letting me vent...

[cAsE sEnSiTiVe]

Ted,

My guess is that you have a bad tube on your hands. Only way for sure to tell, as you said, is to find a tester and run it. Sorry to hear your first foray with that tube didn't go well. Assuming this was an Ebay purchase, might be time to contact the seller. Glad to hear it didn't take out your good fuse.

Bob

[ted_b]

Found a tube tester.  Wow, what a find.  Ended up getting in contact with an elderly man who had sold his repair shop years ago, and then got the itch, so he runs it out of his garage/work area....he has a nice 5 acres at the dead end of a modest street of 1/5 acre lots.  he was the first one there 50 yrs ago and bought the land at the end, and has since built it up into a nice little parklike area.  Come to find out he is the father of one of my high school buddies.  His work area has 17,000 tubes all cataloged in boxes and boxes and boxes.

He tested the tube and it's good....comes up slowly to full power (which he says is the sign of a very long lasting tube), but good nonetheless.  I'll try again tonight (with a cheap fuse) and report back.

Edit:  Fired it up...we have liftoff...we have music (so far so good).   

[rpf]

17,000 tubes????  Wow.   

[rydenfan]

Found a tube tester.  Wow, what a find.  Ended up getting in contact with an elderly man who had sold his repair shop years ago, and then got the itch, so he runs it out of his garage/work area....he has a nice 5 acres at the dead end of a modest street of 1/5 acre lots.  he was the first one there 50 yrs ago and bought the land at the end, and has since built it up into a nice little parklike area.  Come to find out he is the father of one of my high school buddies.  His work area has 17,000 tubes all cataloged in boxes and boxes and boxes.

He tested the tube and it's good....comes up slowly to full power (which he says is the sign of a very long lasting tube), but good nonetheless.  I'll try again tonight (with a cheap fuse) and report back.

Edit:  Fired it up...we have liftoff...we have music (so far so good).   

What a cool story. It is amazing where a day can take us sometimes.

[Bigfish]

I dont believe the GZ33 was originally named as a suitable replacement. I am going to check with Dan and find out.

Now I just need to convince rpf to send me his High Wycombe fat glass GZ37 to try out 

No problem David. I have an extra one and I'd like to hear someone else's thoughts on it. Send me a PM with your address and I'll get it out to you.

Rob

Rob,
Very kewl.  Thanks. 

David,
No pressure...just a $275 per tube investment, riding on your thoughts alone, no one elses!! 

Great Rob, thanks!! 

Damn Ted, that is some serious pressure 

Hi Guys:

Did you ever try the GZ-37 and if so what are your comments?  I am still running a Mullard GZ-32 and the 6H30DR combination and waiting on a 5AR4 (Mullard GZ34) to arrive from Germany to try with the DRs. 

Ken

[rydenfan]

Ken, Rob will be sending me out his GZ-37 today 

[Bigfish]

Ken, Rob will be sending me out his GZ-37 today 

David:

I certainly look forward to reading your review.  You have rolled many tubes through the Transporter and I know you will be able to tell us how the GZ-37 stacks up to your favorites.

Thanks,

Ken

[ted_b]

So it's been 28 hours now and I really like the 5AR4/GZ34 metal base Mullard (Valvo) in combo with the DR's.  It has a very deep, warm sound, but not at all muddy or bloomy.  CD's like Daniel Lanois's Arcadie sound incredible; the classic Lanois-sound of textured acoustic guitar work and ethereal effects...although this is with my backup Bent TAP preamp, a passive TVC-based ss preamp (my Modwright 36.5 is in Amboy for some minor repair).  The TAP, though, is not at all cold or "ss" sounding; just not as musical and deep as my 36.5 DM.  So i'll post back once the 36.5 is back in the path.  I'm very impressed with the metal base, and it will supposedly last forever.

[zybar]

So it's been 28 hours now and I really like the 5AR4/GZ34 metal base Mullard (Valvo) in combo with the DR's.  It has a very deep, warm sound, but not at all muddy or bloomy.  CD's like Daniel Lanois's Arcadie sound incredible; the classic Lanois-sound of textured acoustic guitar work and ethereal effects...although this is with my backup Bent TAP preamp, a passive TVC-based ss preamp (my Modwright 36.5 is in Amboy for some minor repair).  The TAP, though, is not at all cold or "ss" sounding; just not as musical and deep as my 36.5 DM.  So i'll post back once the 36.5 is back in the path.  I'm very impressed with the metal base, and it will supposedly last forever.

I have the Kuhl tube Mullard 1958 Black Base GZ34/5AR4 from Tube World and while I like it, I think I like the Tung-Sol 5U4GB a little more, but I will need to switch back before I can definitely say.

I wonder how the Black Base differs from the metal base?

Here is what Brendan now says on his site for the Black Base:

Double D getter halos, smooth plates.
Same sound as the metal base 5AR4 from 1955-1957
Modwright LS 36.5 power supply

George

[NickS]

Ted,

Have you had to feed the MWTP any more fuses with the new metal base GZ34 rectifier?

Since my MWTP passed its 300th hour of break-in, I have been busy accumulating an impressive number of tubes and doing some serious comparative listening (with pen and paper in hand). 

While my results closely parallel those previously posted here, there have been one or two "surprises".

Will be posting with details shortly.

This is one AMAZING piece of kit, this...

[ted_b]

So it's been 28 hours now and I really like the 5AR4/GZ34 metal base Mullard (Valvo) in combo with the DR's.  It has a very deep, warm sound, but not at all muddy or bloomy.  CD's like Daniel Lanois's Arcadie sound incredible; the classic Lanois-sound of textured acoustic guitar work and ethereal effects...although this is with my backup Bent TAP preamp, a passive TVC-based ss preamp (my Modwright 36.5 is in Amboy for some minor repair).  The TAP, though, is not at all cold or "ss" sounding; just not as musical and deep as my 36.5 DM.  So i'll post back once the 36.5 is back in the path.  I'm very impressed with the metal base, and it will supposedly last forever.

I have the Kuhl tube Mullard 1958 Black Base GZ34/5AR4 from Tube World and while I like it, I think I like the Tung-Sol 5U4GB a little more, but I will need to switch back before I can definitely say.

I wonder how the Black Base differs from the metal base?

Here is what Brendan now says on his site for the Black Base:

Double D getter halos, smooth plates.
Same sound as the metal base 5AR4 from 1955-1957
Modwright LS 36.5 power supply

George

George,
I have both a black base and a fat base black, and also the TS GB.  I like the Tung Sol GB better, too...but the metal base even more so, at least so far with the Bent TAP (big caveat).  The net of this, though, is that I don't agree that the metal base has the same sound as a black base (unless cryo'ing the black base adds that much magic....dunno).

Have you had to feed the MWTP any more fuses with the new metal base GZ34 rectifier?

No, the metal base has behaved itself since last night's new stock 3.15A fuse.

[zybar]

Thanks Ted.

Maybe on my next trip out of town I will send you some tubes to try.

George

[IronLion]

Just thought I'd mention this as I noticed this a while back: on Brendan's Tubeworld page, if you search for the regular (non Kuhl tube) 5ar4 page, it says this about the non-metal base referred to in this thread:

($350 each Kuhl-Tube cryo-treated, sounds nearly the same as the metal base GZ34)

So here at least, he seems to be implying that there is some difference in sound to the two, and one would certainly hope so at almost double the price.  In the end only an email or phone call to him would probably flesh out the differences.  For my part, I'm considering the metal base, but man...$650...

[ted_b]

I got my metal base from Ebay for $150.

[rydenfan]

$650 seems very high. I was offered a 1950's Amperex Holland made Metal Base NOS 5AR4 yesterday for around $350. I understand that to be a pretty good price but I feel like that is a lot for a tube