[trianglezerius]

Like I said earlier I use all EH tubes in my Tempest III with great success that allows me to enjoy the music. 

[Bigfishhk]

Like I said earlier I use all EH tubes in my Tempest III with great success that allows me to enjoy the music. 

Standard EH or those special cyro treated ones?
Thanks

[trianglezerius]

Standard EH or those special cyro treated ones?
Thanks

The inputs are cryo'd the outputs are not.

[Ericus Rex]

Thanks but where to source them? Every place I look (ebay, tubedepot, other audio groups, etc.) they're  running at least $200 pair...

$200/pair for Sylvania 12AU7s!  Are you looking at Sylvania power tubes maybe?  Concerning power tubes, you'll have to stick with new production there.  But you can roll the 9-pins for very little dough to your heart's content.  If you need 12AX7s buy Freo's Raytheons!!!!

Are the tubes fully burnt in?  Don't change them out until you've got at least 100 hours on them.  They may mellow a bit more to your liking.  It is possible the first owner of your amp swapped the stock tubes immediately and put them back in when selling.  Your tubes may not have any hours on them.

[Ericus Rex]

Sylvania Amplitrex-matched 12AX7 pairs starting at $69/pair:

http://tctubes.com/12AX7-ECC33-5751-7025-tubes.aspx?page=2


Sylvania Amplitrex-matched 12AU7 pairs starting at $42/pair (Raytheons $39/pr):

http://tctubes.com/12AU7-ECC32-5814A-6189-7316-tubes.aspx


Telefunken 12AX7 $120/pair:

http://www.tubeaudiostore.com/tubes.html


I would buy primo tubes from these guys, due to their excellent quality testers used, instead of giving the other guys, who use some old tester they found on ebay, loads of my dough for questionably tested tubes at high prices.

Have fun!

[Alexdad54]

No, I was looking at $200 for Sylvania 3-mica black-plate, gold pin 12AX7's....the previous owner told me he never changed out any tubes on the Cronus after buying it so I assume that they're the stock tubes with probably well over 100 hours on them. I'm leaving the stock KT-120 power tubes in place. I am gonna try Freo's 's suggestion today, the prices look great....

A question, when I swap out the 12AX7's should I also be looking at changing  the 12AU7's?....

Update: thanks for the links, I'll take a look.

[roscoeiii]

The 12ax7s are the input tube right? Those will make the biggest difference. I'd just concentrate on them for now.

And yeah, I'd stick with the KT120s as output tubes. They are much loved.

[Alexdad54]

Sylvania Amplitrex-matched 12AX7 pairs starting at $69/pair:

http://tctubes.com/12AX7-ECC33-5751-7025-tubes.aspx?page=2


Sylvania Amplitrex-matched 12AU7 pairs starting at $42/pair (Raytheons $39/pr):

http://tctubes.com/12AU7-ECC32-5814A-6189-7316-tubes.aspx


Telefunken 12AX7 $120/pair:

http://www.tubeaudiostore.com/tubes.html


I would buy primo tubes from these guys, due to their excellent quality testers used, instead of giving the other guys, who use some old tester they found on ebay, loads of my dough for questionably tested tubes at high prices.

Have fun!

In reading around, I get the impression that all these Sylvanias have different sonic characteristics...lots of choices, appreciate any tips on which ones....

The center 12AU7 is the preamp tube, doesn't that also influence the sound of the Cronus?

[Ericus Rex]

The center 12AU7 is the preamp tube and will have a big influence on the sound.  The great thing there is that singles are cheaper than pairs (usually 30-40% of a pair), and 12AU7s are cheaper than 12AX7s so you may get a few different things to try out for little money.  The next biggest improvement should be the 12AX7s as I believe they are the voltage gain tubes.  The 12AU7 pair is probably power tube drivers.  Some say they also make a big difference but I personally haven't found driver rolling to lead to much change.  Perhaps it's circuit dependent.  I have not compared the different Sylvania types.  Give TC tubes a call or send an email letting them know what kind of sound you're looking for and Tyler can probably make some recommendations.

[HAITIMAN]

No, I was looking at $200 for Sylvania 3-mica black-plate, gold pin 12AX7's....the previous owner told me he never changed out any tubes on the Cronus after buying it so I assume that they're the stock tubes with probably well over 100 hours on them. I'm leaving the stock KT-120 power tubes in place. I am gonna try Freo's 's suggestion today, the prices look great....

A question, when I swap out the 12AX7's should I also be looking at changing  the 12AU7's?....

Update: thanks for the links, I'll take a look.
[/quote
Alex, I have a Cronus Magnum and have settled on the following arrangement after some experimentation:
12AX7 -2 Tungsram (1970's vintage)
12AU7 preamp position - Telefunken smoothplate (early '60s)
12AU7 2 RCA Cleartop (Conn Organ pulls)
I tried an RCA Cleartop in the preamp position but it couldn't match the Tele for depth of soundstage and overall balance....but it was close.
I have a set of Mullard CV4004 and CV4003 from the 1980's, however, for me, they were a bit blurry. I know they need more break-in time.
The Amp came with an old GE triple mica 5814A (installed from the factory) and it is very good, as well. A bit more forward than the Tele.
Just my 2 cents.

[HAITIMAN]

Alex, I have a Cronus Magnum and have settled on the following arrangement after some experimentation:
12AX7 -2 Tungsram (1970's vintage)
12AU7 preamp position - Telefunken smoothplate (early '60s)
12AU7 2 RCA Cleartop (Conn Organ pulls)
I tried an RCA Cleartop in the preamp position but it couldn't match the Tele for depth of soundstage and overall balance....but it was close.
I have a set of Mullard CV4004 and CV4003 from the 1980's, however, for me, they were a bit blurry. I know they need more break-in time.
The Amp came with an old GE triple mica 5814A (installed from the factory) and it is very good, as well. A bit more forward than the Tele.
Just my 2 cents.

[Captainhemo]

Another good spot to  look for NOS  tubes is Brent Jessee
http://www.audiotubes.com/12ax7.htm

Quite a bit of info and good selection

-jay

[roscoeiii]

Alex, I have a Cronus Magnum and have settled on the following arrangement after some experimentation:
12AX7 -2 Tungsram (1970's vintage)
12AU7 preamp position - Telefunken smoothplate (early '60s)
12AU7 2 RCA Cleartop (Conn Organ pulls)
I tried an RCA Cleartop in the preamp position but it couldn't match the Tele for depth of soundstage and overall balance....but it was close.
I have a set of Mullard CV4004 and CV4003 from the 1980's, however, for me, they were a bit blurry. I know they need more break-in time.
The Amp came with an old GE triple mica 5814A (installed from the factory) and it is very good, as well. A bit more forward than the Tele.
Just my 2 cents.

What did you like about the Tungsram 12AX7s compared to other 12AX7s you tried?

[Ericus Rex]

What did you like about the Tungsram 12AX7s compared to other 12AX7s you tried?

I've never been able to test any Tungsram tubes in my system but a reliable friend and dealer says they are highly underated/underappreciated tubes that sound fantastic.  The only caveat with them, according to him, is they can be quite noisy and must be tested for noise.

[Bigfishhk]

This is a question re the 6sn7 tubes in the rogue 99 pre amp. Apparently two of the tubes positions are the most important and should have the better tubes. The are some AG threads to this effect.

Just wondering if anyone can confirm that this is true, and also that it,s fine to have 2 different brand of tubes- ie 2 matched pairs one on each side?



Thanks
Tom

[Robert Martellaro]

This is a question re the 6sn7 tubes in the rogue 99 pre amp. Apparently two of the tubes positions are the most important and should have the better tubes. The are some AG threads to this effect.

Tom,

The tubes on the right, looking from the front of the unit, are the gain stages, and if I remember correctly, the tubes at the back are for the left channel. The tubes on the left are the cathode/mu followers. WRT tube position and sound, I hear a significant difference when I change the follower tubes. If I had to assign a number to that, considering what I hear and what others have reported, I'd guess 60/40 gain/follower. 

Just wondering if anyone can confirm that this is true, and also that it,s fine to have 2 different brand of tubes- ie 2 matched pairs one on each side?

Yes.

Robert

[Bigfishhk]

Tom,

The tubes on the right, looking from the front of the unit, are the gain stages, and if I remember correctly, the tubes at the back are for the left channel. The tubes on the left are the cathode/mu followers. WRT tube position and sound, I hear a significant difference when I change the follower tubes. If I had to assign a number to that, considering what I hear and what others have reported, I'd guess 60/40 gain/follower. 


Yes.

Robert

Thanks for the feedback. I rolled 2 x RCA 6sn7 into right side positions and left EH on left side. So far so very good. I am in honeymoon period with the Rogue 99!

Meanwhile my very limited comparisons in my rogue 99 / tempest (same as rogue90) set up for 12ax7

12ax7 vs 5751-

Psvane treasure 12ax7. Biggest bass, good dynamics
Telefunken 12ax7. Smoothest, sweetest presentation of my 12ax7's
EH 5751 (cyro gold)   Possibly my favorite. Just plain musical, involving, sweet and transparent.  Have no idea if the 5751 benefits from cyro treatment and not opening that can of worms.

I would be happy with any of the above but the Eh are by far the lowest price.

Tom

[Captainhemo]

Just curioous,  has anyone   compared the  EH 5751 Gp to the EH 12AX7 GP   ?    Been thinking of giving these 5751's a try but am wondering about the  12AX7's from the same  manufactuer.  When I asked Ron at cryoset about it, he said  that usually the 5751  is only used in "problem" designs  and that the  EH 12AX7 GP  would be more dynamic.
Currently I'm running  Baldwin (Raytheon)   12AX7 and am happy with them but  with the price of  NOS tubes  going up all the time,  I'd like to find a   current production tube that I'm happy with
Curious to know if  anyone  has listened to both of the EH  gold pin versions and what  the differences were

-jay

[Bigfishhk]

Just curioous,  has anyone   compared the  EH 5751 Gp to the EH 12AX7 GP   ?    Been thinking of giving these 5751's a try but am wondering about the  12AX7's from the same  manufactuer.  When I asked Ron at cryoset about it, he said  that usually the 5751  is only used in "problem" designs  and that the  EH 12AX7 GP  would be more dynamic.
Currently I'm running  Baldwin (sylvania I guess)   12AX7 and am happy with them but  with the price of  NOS tubes  going up all the time,  I'd like to find a   current production tube that I'm happy with
Curious to know if  anyone  has listened to both of the EH  gold pin versions and what  the differences were

-jay

I asked MArk O'Brien about using 5751 in the Tempest and he said they were good. I am not sure they are only for 'problem' designs but I am no expert.

[Captainhemo]

I asked MArk O'Brien about using 5751 in the Tempest and he said they were good. I am not sure they are only for 'problem' designs but I am no expert.

I think what he was saying  wasn't so much " they are ONLY  for a problem cirucit" but that if there wasn't a problem where the lower gain was needed,   he didn't see the benifit using them and that the higher gain 12aX7 would be more dynamic.
That is how  I interpeted it  anyway,  I wasn't very clear in the  wording

-jay