ModWright Transporter Tube Rolling Thread.....!

zybar · « **Reply #980 on:** 10 Mar 2009, 01:22 pm »

Regardless of whether the rectifier or signal tubes has a larger impact on the sound, I find it interesting that people don't seem to have too much of a problem with shelling out $200+ for a single EML rectifier tube, but are hesitant to buy a pair of Tung Sol Round Plates for $320-450.

While I know that the Round Plates cost more in actual dollars, they have an established price in the market and are potentially going up in value. If you were to try the Round Plates and not feel that they are worth that level of investment, you should be able to pretty much get your money back, or if you hold on to them, maybe even make some money down the road. Also, I believe there is a much larger potential market for the Round Plates vs. the EML tube.

In no way am I trying to put down the EML tube, nor do I have any financial interests associated with the Round Plates. Just simply throwing out a few thoughts.

George

rpf · « **Reply #981 on:** 10 Mar 2009, 01:33 pm »

Quote from: zybar on 10 Mar 2009, 01:22 pm

Regardless of whether the rectifier or signal tubes has a larger impact on the sound, I find it interesting that people don't seem to have too much of a problem with shelling out $200+ for a single EML rectifier tube, but are hesitant to buy a pair of Tung Sol Round Plates for $320-450.

While I know that the Round Plates cost more in actual dollars, they have an established price in the market and are potentially going up in value. If you were to try the Round Plates and not feel that they are worth that level of investment, you should be able to pretty much get your money back, or if you hold on to them, maybe even make some money down the road. Also, I believe there is a much larger potential market for the Round Plates vs. the EML tube.

In no way am I trying to put down the EML tube, nor do I have any financial interests associated with the Round Plates. Just simply throwing out a few thoughts.

George

But don't rectifiers last significantly longer than signal tubes? At least that's what I thought.

Rob

Marco Prozzo · « **Reply #982 on:** 10 Mar 2009, 02:16 pm »

I was just composing a post that asked a similar question to George...

I've been going through the thread a bit, but checking all 49 pages is a daunting task. So forgive me if this has been covered: Has anyone tried the EML 274A/B tube? How about the Svet 5U3C? I've tried a few NOS Mullard 5AR4's and found it just softens everything out a bit too much for my taste (with RCA 6CG7 cleartops). TungSol 5u4g big bottle (mid 50's I think) is currently in, but I think I preferred the RCA 5u4G. I'm going to leave it in there for a while and go back. There are so many affordable (read: available) rectifiers out there - it's interesting that everyone is so drawn to the most expensive (read: exclusive, scarce) variants. Has anyone done any blind testing (with the help of a friend) to see if their preference held up? I do know how significant a difference an input tube or a driver tube can make, but my own experiences with rectifiers (mostly in amplifiers) does not seem to reflect the , "....my god, it's like having a brand new component..." epiphany that I'm reminded of when reading folks experiences with the EML tube. I'm open to the possibility of change, certainly, and I know they certainly can and do make a difference. But for the price of a single EML you can get perhaps 8 tungsol variants or other, more readily available NOS...is it really THAT much better than all of them?

tdangelo · « **Reply #983 on:** 10 Mar 2009, 02:38 pm »

anyone know if the 5r4gy rectifier can be used in the Transporter?

thanks
Tony

Philistine · « **Reply #984 on:** 10 Mar 2009, 02:47 pm »

Quote from: tdangelo on 10 Mar 2009, 02:38 pm

anyone know if the 5r4gy rectifier can be used in the Transporter?

thanks
Tony

Tony, based on the recent issues with the Shuguang 6SN7 tubes, and the EML 5U4G, I would play safe and get the green light from Dan before trying anything different.

tdangelo · « **Reply #985 on:** 10 Mar 2009, 02:49 pm »

Quote from: Philistine on 10 Mar 2009, 02:47 pm

Quote from: tdangelo on 10 Mar 2009, 02:38 pm
anyone know if the 5r4gy rectifier can be used in the Transporter?

thanks
Tony

Tony, based on the recent issues with the Shuguang 6SN7 tubes, and the EML 5U4G, I would play safe and get the green light from Dan before trying anything different.

good idea

zybar · « **Reply #986 on:** 10 Mar 2009, 02:53 pm »

Quote from: rpf on 10 Mar 2009, 01:33 pm

But don't rectifiers last significantly longer than signal tubes? At least that's what I thought.

Rob

I thought signal tubes can go for 10,000+ hours. How long is the rectifier supposed to last?

George

Philistine · « **Reply #987 on:** 10 Mar 2009, 03:26 pm »

Quote from: Marco Prozzo on 10 Mar 2009, 02:16 pm

I was just composing a post that asked a similar question to George...

I've been going through the thread a bit, but checking all 49 pages is a daunting task. So forgive me if this has been covered: Has anyone tried the EML 274A/B tube? How about the Svet 5U3C? I've tried a few NOS Mullard 5AR4's and found it just softens everything out a bit too much for my taste (with RCA 6CG7 cleartops). TungSol 5u4g big bottle (mid 50's I think) is currently in, but I think I preferred the RCA 5u4G. I'm going to leave it in there for a while and go back. There are so many affordable (read: available) rectifiers out there - it's interesting that everyone is so drawn to the most expensive (read: exclusive, scarce) variants. Has anyone done any blind testing (with the help of a friend) to see if their preference held up? I do know how significant a difference an input tube or a driver tube can make, but my own experiences with rectifiers (mostly in amplifiers) does not seem to reflect the , "....my god, it's like having a brand new component..." epiphany that I'm reminded of when reading folks experiences with the EML tube. I'm open to the possibility of change, certainly, and I know they certainly can and do make a difference. But for the price of a single EML you can get perhaps 8 tungsol variants or other, more readily available NOS...is it really THAT much better than all of them?

Marco, I see a number of variables in the tube selection process - personal taste, other equipment (synergy) and room etc. When we started the early tube rolling activities the preferences on rectifier tubes seemed to shift into two broad camps: 5U4G and GZ34, with the individual preferences being the Tung Sol 5U4G and the metal base GZ34. Prices for both then started to increase and most of the available tubes at a 'reasonable' price were used, for example a used metal base GZ34 was around $200 compared with a NOS at over $600. Along comes the EML 5U4G, which most of us find combines all the strengths of the 5U4G and GZ34, and also adds a dose of something else in addition. Furthermore a significant buying risk is eliminated as the performance is consistent, it's available from a reputable source, the price is fixed and it has a guarantee. In contrast I have a boxful of used vintage tubes, some that have failed and some that are going strong. Given the view that it's considered a strong performer and a 'safe' purchase it's very easy to see its attraction and why the majority of the owners do consider it THAT much better, you get the best rectifier tube with minimal risk. As most of us have started with the 5U4G/GZ34, and then moved on to the EML, it is difficult to take a backwards step. I consider these factors explain why the the EML tube is so popular.

As I currently cannot use the EML I've had to go back to using my other rectifier tubes, for the last few days I've been using an old Emerson 5U4G with the Tung Sol 6SN7 round plates - the combination works very well and makes great music. For those that cannot use the EML, or choose not to go down the EML path, I agree with George in that you can have a great sounding system based on these signal tubes. But again the downside with these tubes is that the buying risk is increased and you have to screw around with adapters, this increases the cost and each adapter currently available isn't perfect. This is one of the reasons I explored the Shuguang 6SN7 last week, if it worked out it would have given us the option of having a readily available, low risk, new tube without the risk and scarcity issues. Some of us are prepared to take greater risk and experiment, others just want to lower the risk and listen to music. I understand all this, unfortunately I fall in the high risk experimenters camp, with the wrong caps

NB
I believe the EML 274A/B is the same tube in terms of spec as the EML 5U4G, but has a different pin layout - not 100% sure on this.

owenmd · « **Reply #988 on:** 10 Mar 2009, 03:29 pm »

The EML 274B tube is a much worse choice for the Transporter than the 5U4 simply because of the capacitance issue.... check out the EML website and the tech notes.

Quote from: Marco Prozzo on 10 Mar 2009, 02:16 pm

I was just composing a post that asked a similar question to George...

I've been going through the thread a bit, but checking all 49 pages is a daunting task. So forgive me if this has been covered: Has anyone tried the EML 274A/B tube? How about the Svet 5U3C? I've tried a few NOS Mullard 5AR4's and found it just softens everything out a bit too much for my taste (with RCA 6CG7 cleartops). TungSol 5u4g big bottle (mid 50's I think) is currently in, but I think I preferred the RCA 5u4G. I'm going to leave it in there for a while and go back. There are so many affordable (read: available) rectifiers out there - it's interesting that everyone is so drawn to the most expensive (read: exclusive, scarce) variants. Has anyone done any blind testing (with the help of a friend) to see if their preference held up? I do know how significant a difference an input tube or a driver tube can make, but my own experiences with rectifiers (mostly in amplifiers) does not seem to reflect the , "....my god, it's like having a brand new component..." epiphany that I'm reminded of when reading folks experiences with the EML tube. I'm open to the possibility of change, certainly, and I know they certainly can and do make a difference. But for the price of a single EML you can get perhaps 8 tungsol variants or other, more readily available NOS...is it really THAT much better than all of them?

valvesaglowin · « **Reply #989 on:** 10 Mar 2009, 03:50 pm »

Phil:
Here are the specs on the tubes you had questions about....

5U4...5 volts/3 amps...octal base

5Z3...same as 5U4 with a 4 pin base

274a..5 volts/2 amps with 4 pint base

274B..same as 274A with an octal base

best,

George

ted_b · « **Reply #990 on:** 10 Mar 2009, 03:58 pm »

The 274B is NOT a tube for the Transporter. The Sophia requires a first cap less than 10uf, and the EML and Western Electric less than 4uf! I'm not sure if the "first capacitor (c1)" value is considered the TP's dual caps in series (i.e 2 100uf's equal 50uf, 2 22uf's equal 11uf) or truly the first cap only, but regardless the math doesn't work.

Berto · « **Reply #991 on:** 10 Mar 2009, 04:01 pm »

Quote from: zybar on 10 Mar 2009, 02:53 pm

Quote from: rpf on 10 Mar 2009, 01:33 pm
But don't rectifiers last significantly longer than signal tubes? At least that's what I thought.

Rob

I thought signal tubes can go for 10,000+ hours. How long is the rectifier supposed to last?

George

I just posed same ? to George, the EML distributor, no clue about NOS rectifiers as I don't even own one. Was told when I bought my RCA 6SN7 Vt-231s that they are generally good for 3000+, but did notice the 5692's are rated at 10,000. I'm curious now too, so will advise at least on the EML.
OK (quick response)was just informed the EML will operate for 1-2 years under conservative operating parameters, but he did say in this thread (more specifically) he has had his for 2yrs and about 2000hrs if I read correctly.

valvesaglowin · « **Reply #992 on:** 10 Mar 2009, 04:13 pm »

Rob:
It's better to have modest expectations here. Afterall, some people are using these tubes in their power amps. I'm in the third year of usage with my 5Z3 tube in my own built power amplifier. I run my tubes conservatively.

Best,

George

ted_b · « **Reply #993 on:** 10 Mar 2009, 04:21 pm »

Question/poll:
Who leaves their MW TP on 24/7 (not counting vacations,etc), and for those that don't, how long do you allow for warm-up before serious listening?

zybar · « **Reply #994 on:** 10 Mar 2009, 04:25 pm »

Quote from: ted_b on 10 Mar 2009, 04:21 pm

Question/poll:
Who leaves their MW TP on 24/7 (not counting vacations,etc), and for those that don't, how long do you allow for warm-up before serious listening?

My TP is on all the time, but the tubed section gets turned on/off depending on use.

My amps take a good 30-60 minutes to sound their best (19 tubes in pure Class A per mono block - OUCH!), so I am not too concerned about TP and its warm-up period.

George

valvesaglowin · « **Reply #995 on:** 10 Mar 2009, 04:55 pm »

Leaving a tube amplifier on 24/7 makes no sense at all

. I can say with certainty that you will be replacing tubes on a premature basis. These comments are primarilly related to output tubes and rectifier tubes.

George

ted_b · « **Reply #996 on:** 10 Mar 2009, 05:00 pm »

George H,
Thanks. An yes, I was speaking of the tube section. And l would not recommend externally powering down the TP regularly (front or remote power button is simple a sleep mode; doesn't count) as many have said a DAC chip takes a good 48-72 hrs to settle in.

George L,
I hope no one is saying they are leaving tube amps powered up? Yikes. Do you carry that opinion over to the TP as well? Tube preamps, like the 36.5?

valvesaglowin · « **Reply #997 on:** 10 Mar 2009, 05:08 pm »

Ted:
I'm less concerned with signal tubes. With rectifiers, you are sort of in a no win situation. Rectifier tubes take the most abuse when being turned on. Leaving them on indefinitely does not increase the life of the tube either. This is why many electronic designers use SS diodes instead of tube rectification. The problem with SS rectification is that most prefer tube to SS. Pick your poison here!

ted_b · « **Reply #998 on:** 10 Mar 2009, 05:22 pm »

Well, in the case of the TP and pre (36.5) they use tube rectification (duals in the 2 box 36.5) so i guess I'll turn mine off every night.

rpf · « **Reply #999 on:** 10 Mar 2009, 06:06 pm »

I've been told by more than one person very knowledgeable about tubes that NOS Mullard rectifiers will last at least 10,000 hours.

I don't have a lot of experience with signal tubes. The 5687s I've had in various Modwright products seem to undergo sonic degradation (loss of resolution and the frequency extremes) by 2000 hours; such that I feel the need to change them.

I don't leave my (all tube) gear on overnight but I do leave it on all day once it's been turned on (unless I know I won't be listening again, of course).
Given the prices for high quality (usually NOS) tubes, standby switches are, IMO, a must on all tube equipment. I have them on my amps (Dodds) and I've asked Dan to look into devising one for the 36.5 (the Home Theater bypass switch - which I don't need - would be a perfect location for me).