Marantz 7 and 8B / Homade variac

[uenjoymyself]

Thanks Crooner,

NO! The fuse did not blow nor did the light come on after replacing it with a new one. With power on no indicator light on yet power at the outlets on the back???? Like i said I just stand back in these situations and let him work. He has says "not to worry" and I know and trust him so, I wont.

I was just checking E pay for tubes and saw 4 factory platinum matched Svetlana EL34's by "new sensor"? Im clueless when it comes to tubes and these didnt say anything about "wings" or "c's" lol

I'll look for the ones you've recommended. THANKS!

Ill let you know what I find out about the seven when I hear something.

Meantime TUBES TUBES TUBES!!!!!!!!!!!!!

 

[crooner]

If the fuse did not blow, then most likely you'll be fine. The lamp may not glow because your low voltage selenium rectifier is too weak (or soft) to produce a reasonable output voltage.

Beware of the New Sensor Svetlana. Not the same as the original Svetlana now called SED or "Winged C". If you buy a current production quad of Winged C, make sure you buy from a reputable source. Any tube marked Svetlana with a date code later than 2000 or "00" is most likely a New Sensor tube.

The older 1990's versions appear from time to time. I scored a quad of 1999 NOS Svetlana's for $30 the other day, so keep an eye open for them. They are well worth it.

Thanks Crooner,

NO! The fuse did not blow nor did the light come on after replacing it with a new one. With power on no indicator light on yet power at the outlets on the back???? Like i said I just stand back in these situations and let him work. He has says "not to worry" and I know and trust him so, I wont.

I was just checking E pay for tubes and saw 4 factory platinum matched Svetlana EL34's by "new sensor"? Im clueless when it comes to tubes and these didnt say anything about "wings" or "c's" lol

I'll look for the ones you've recommended. THANKS!

Ill let you know what I find out about the seven when I hear something.

Meantime TUBES TUBES TUBES!!!!!!!!!!!!!

 

[mech986]

NEXT QUESTION: I want to replace at least the power tubes in the 8B. Im sure this question is right up there with which interconnect to use as these things are subjective to user preference BUT... Id like a nice matching set that closely match the original equipment or better without spending a gagillion dollars. Without too much effort I have located 2 PAIR of new matched mallard reissue EL34's for $48.00 a pair. so about $100. Or, a quad set of matched, new, jj tesla's for $69.00

Is this simply too little to spend on tubes? I've pretty much blown my hobby budget for the month.

Im a total tube NEWBIE so If I sound naive thats because I am!!

Recomendations on tubes. New vs used. expensive vs cheap. Upgrades and what NOT to use are greatly appreciated!

CHEERS

I think the Mullard reissue EL34's if matched properly would offer a good value at the price. I wouldn't get the Mallard versions, they tend to quack too much But seriously, if you have some decent vintage tubes already matched in there I'd prefer to use them. However, it appears 3 of them are the tall medium slim European types like Mullard (old) or Amperex/Siemens. The one on the right back channel looks a bit larger like an American (GE/Sylvania) 6CA7/EL34. If you can get some closeups of the tubes and their markings we could help you.

Might consider asking your tech to match up the best of the 3 tubes, and then search for one additional set to use in the other channel, and keep the other 2 for spares. One pair of good matched NOS or older used real Mullards might set you back $50 to $100 but you might get a good score somewhere. Barter Town (as a subscriber) could also yield some good tubes from a good WTB (want to buy) ad.

 

[uenjoymyself]

:stupid:

I think the Mullard reissue EL34's if matched properly would offer a good value at the price. I wouldn't get the Mallard versions, they tend to quack too much But seriously, if you have some decent vintage tubes already matched in there I'd prefer to use them. However, it appears 3 of them are the tall medium slim European types like Mullard (old) or Amperex/Siemens. The one on the right back channel looks a bit larger like an American (GE/Sylvania) 6CA7/EL34. If you can get some closeups of the tubes and their markings we could help you.

Might consider asking your tech to match up the best of the 3 tubes, and then search for one additional set to use in the other channel, and keep the other 2 for spares. One pair of good matched NOS or older used real Mullards might set you back $50 to $100 but you might get a good score somewhere. Barter Town (as a subscriber) could also yield some good tubes from a good WTB (want to buy) ad.

Great! now were getting somewhere!

Yes these are siemens/germany except for the "fat" Sylvania. The 6Bh6's and the 6CG7's are RCA

Lesson learned!! Marantz 8B is TOP HEAVY!!!!! As I discovered in transport to the Techs home. stopping at a light the 8B on the floor board of my vehicle began to tip and bumped the bottom of my dash resulting in a broken tube:dammit: no further damage was incurred and the amp tested near perfect with a "spare" EL34 borrowed from one of his 9's. needless to say Im in the market for a new set.

Found these. What is a reasonable price for them? Are these as you describe?

Matched Quad (4) of Mullard, branded GE Great Britain, EL34/6CA7 tubes. All have same Blackburn XF 2 B8A2 date codes. Clean Welded plates, Double Halo, OO getters, nice getters, holes in guide pins. Tested excellent, very strong, and close on Hickok 750 @ 5900, 5800, 5800 and 5800 mhos. Minimum good on this tester is 3800 mhos. New spec is 6000 mhos A very nice quad of desireable, vintage XF 2 Mullards.

I did say "Mallards" didnt I :stupid: lol

 

[mech986]

:stupid:

Great! now were getting somewhere!

Yes these are siemens/germany except for the "fat" Sylvania. The 6Bh6's and the 6CG7's are RCA

Lesson learned!! Marantz 8B is TOP HEAVY!!!!! As I discovered in transport to the Techs home. stopping at a light the 8B on the floor board of my vehicle began to tip and bumped the bottom of my dash resulting in a broken tube:dammit: no further damage was incurred and the amp tested near perfect with a "spare" EL34 borrowed from one of his 9's. needless to say Im in the market for a new set.

Found these. What is a reasonable price for them? Are these as you describe?

Matched Quad (4) of Mullard, branded GE Great Britain, EL34/6CA7 tubes. All have same Blackburn XF 2 B8A2 date codes. Clean Welded plates, Double Halo, OO getters, nice getters, holes in guide pins. Tested excellent, very strong, and close on Hickok 750 @ 5900, 5800, 5800 and 5800 mhos. Minimum good on this tester is 3800 mhos. New spec is 6000 mhos A very nice quad of desireable, vintage XF 2 Mullards.

I did say "Mallards" didnt I :stupid: lol

DAMN! That's a shame to lose one of those Siemens! But exactly what happened to me and my 8B after last year's SoCal AK event, mine tipped in the carry box I had it in when I lifted the box and pulled it to my body. Damaged a GE/Sylvania fat boy like you have.

From now on, my policy is transport the amp without tubes, and mark with a small color dot from a sharpie to match the tubes to channels.

Sounds like the Quad of vintage Mullards would be a pretty good choice with the other 2 siemens left as a backup pair, assuming they match reasonably well.

 

[uenjoymyself]

If the fuse did not blow, then most likely you'll be fine. The lamp may not glow because your low voltage selenium rectifier is too weak (or soft) to produce a reasonable output voltage.

Beware of the New Sensor Svetlana. Not the same as the original Svetlana now called SED or "Winged C". If you buy a current production quad of Winged C, make sure you buy from a reputable source. Any tube marked Svetlana with a date code later than 2000 or "00" is most likely a New Sensor tube.

The older 1990's versions appear from time to time. I scored a quad of 1999 NOS Svetlana's for $30 the other day, so keep an eye open for them. They are well worth it.

Thanks for your help!

I have found these SED winged C,s matched quads for $144. If they carry the SED and winged C logo are they the real deal? I doubt these are pre 1999 since there seems to be an abundance of them for sale by various different vendors.

Still have my eyes on the Mullards

Cheers

 

[crooner]

Thanks for your help!

I have found these SED winged C,s matched quads for $144. If they carry the SED and winged C logo are they the real deal? I doubt these are pre 1999 since there seems to be an abundance of them for sale by various different vendors.

Still have my eyes on the Mullards

Cheers

They are current production tubes. Not bad, but somehow I find the older ones to sound better.

 

[uenjoymyself]

They are current production tubes. Not bad, but somehow I find the older ones to sound better.

So, I should be looking for pre 99 Svetlana el34 made in St Petersburg russia?
Did you pay $30 for a quad or is that each?

How do you feel about the Mullard reissue made by new sensor.

Too many choices:headscrat

 

[crooner]

So, I should be looking for pre 99 Svetlana el34 made in St Petersburg russia?
Did you pay $30 for a quad or is that each?

How do you feel about the Mullard reissue made by new sensor.

Too many choices:headscrat

Hi:
Ideally yes, but it may be a while until you find a nice quad, and it may not be $30. I just lucked out on a quad that had horrible pics and description.

I just received a single EL34 today that is Svetlana Winged C with 2000 production codes. Looks identical to the 1990's types. Less than 10 bucks with shipping. I always like to have an extra single tube of the same type just in case one dies in a quad.

The current production Winged C, if properly screened, should be satisfactory. So, would the New Sensor Mullard. Though, I tend to prefer the reissue KT77 from them. Works nice in the 8B.

Like I said before, keep an eye out for a quad of Siemens/RFT EL34's. I got a barely used quad for $125 a couple of months back. They are reliable, look superb and sound fantastic on the Marantz.

 

[uenjoymyself]

Are these the original Svetlana's made in St Petersburg Germany as the seller claims. Are the #s shown the 1999 date codes?

Thanks, still shopping!

 

[crooner]

Are these the original Svetlana's made in St Petersburg Germany as the seller claims. Are the #s shown the 1999 date codes?

Thanks, still shopping!

Yes, but St Petersburg, Russia. They were made before New Sensor acquired the rights to the Svetlana name.

Should be very sweet sounding tubes, very much like Mullards but with a touch of high end "sparkle".

 

[uenjoymyself]

Yes, but St Petersburg, Russia. They were made before New Sensor acquired the rights to the Svetlana name.

Should be very sweet sounding tubes, very much like Mullards but with a touch of high end "sparkle".

OOP's my bad ! I did mean Russia.

Thank you, now I know exactly what to look for. I'll let you know what I find:thmbsp: These are $100 for the pair so I may wait and see if I can find a sweeter deal. Are the numbers on the tubes, 9904, the date codes? 99 year and o4 month?

Thanks again!!

 

[uenjoymyself]

P.S. Should there be a missing pin? looks like the #6 pin is missing on both tubes(not pictured) None of my Siemens tubes are missing pins. Perhaps this is normal construction for the svets?

Thanks for ALL the valuable info Crooner!

 

[crooner]

P.S. Should there be a missing pin? looks like the #6 pin is missing on both tubes(not pictured) None of my Siemens tubes are missing pins. Perhaps this is normal construction for the svets?

Thanks for ALL the valuable info Crooner!

Pin 6 is not used on the EL34. Some manufacturers still include the pin in the base, some don't. Electrically it does not matter.

 

[uenjoymyself]

Crooner, Just found and bought this quad with 00 date codes for $75. What do you think? I did some research and found that new sensor didn't acquire the rights to Svetlana until 01 so Im hoping these are the same as the 99s and are from the St Petersburg factory like the ones in my previous post. They look identical.

Whats your take on these? did I do ok? Fingers crossed.

Description and pics from seller:

Here is a matched quad of near new Svetlana SED vacuum tubes. Emission reads 100, 100, 105, 105 where 70 is the minimum good and 110 is the reading for a new tube. Transconductance reads 5900, 5800, 5800, 5800 where 3850 is the min. good and 6000 is the reading for a new tube. All 4 have identical construction with dual parasol disc getters in each. They tested good for shorts and gas. I ship only to the 48 United States. Check out my other items for more interesting electronic and hifi stuff. Thanks for looking.

 

[crooner]

They look like the real deal to me. Congrats!
Should sound sweet on your 8B.

 

[uenjoymyself]

They look like the real deal to me. Congrats!
Should sound sweet on your 8B.

Great! Thank you for all your advice!

Cheers!

 

[crooner]

You are in for a treat, as the 8B is a thing of beauty. I recommend you purchase a pair of E90F's to replace the 6BH6's. The improvement in sound quality is *not* subtle!

 

[uenjoymyself]

You are in for a treat, as the 8B is a thing of beauty. I recommend you purchase a pair of E90F's to replace the 6BH6's. The improvement in sound quality is *not* subtle!

Sweet! Are these a drop in replacement for the 6bh6's? Do I have to do anything to the amp to run these? The 8B is totally stock and I wouldn't want to do anything that might strain the 50 year old internals.

I have found these, will they do? Phillips or Mullard? They're both from the same factory. Being new to tubed gear its great to have your expertise! Thanks again!



NOS E90F tubes with mesh plates from a factory bulk pack. The codes on the tube indicate that these were made at the Philips plant in Heerlen, Holland...Some are labeled Philips and some Mullard...both have same factory codes

 

[crooner]

No modification required. Exact electrical equivalent. Those appear to be real.