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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 169

post #2521 of 5900
Quote:
Originally Posted by siles1991 View Post

if you dont mind me asking what are the guidelines on whether the tubes can be used or not?

 

In short, you grab a datasheet for the tube (6AN5) and look at the pin diagram. And then you compare the pinout to the EF1, EF92 and EF95. If the pinout is the same, you can simply plug it in, as appropriate. In the case of the 6AN5, you can see that the Beam Plates/Grid 3 and the Cathode are strapped together inside the tube. And if you compare this to the EF95 pinout, you will see the identical pattern. Therefore, I can see no reason why this tube wouldn't work in the EF95 setting.

 

And this is the reason we strap pins in the socket: To make the tube pinout appear to be an  EF91, EF92 or EF95 so that we can then use them in the LD.

post #2522 of 5900
Quote:
Originally Posted by gibosi View Post

 

In short, you grab a datasheet for the tube (6AN5) and look at the pin diagram. And then you compare the pinout to the EF1, EF92 and EF95. If the pinout is the same, you can simply plug it in, as appropriate. In the case of the 6AN5, you can see that the Beam Plates/Grid 3 and the Cathode are strapped together inside the tube. And if you compare this to the EF95 pinout, you will see the identical pattern. Therefore, I can see no reason why this tube wouldn't work in the EF95 setting.

 

And this is the reason we strap pins in the socket: To make the tube pinout appear to be an  EF91, EF92 or EF95 so that we can then use them in the LD.

ahhhhhh i see thanks for enlightening me on this!!! So i assume even the 6GK5 could work since its connected 1/7?


Edited by siles1991 - 8/20/13 at 8:51pm
post #2523 of 5900
Quote:
Originally Posted by siles1991 View Post

ahhhhhh i see thanks for enlightening me on this!!! So i assume even the 6GK5 could work since its connected 1/7?

 

No....

 

LD amps expect that Grid 1 is always on Pin 1 and the Cathode is always on Pin 2. In the 6GK5, Grid 1 is on Pin 2 and the Cathode is on Pin 1.. So, you would somehow have to interchange pins 1 and 2 in order to get this tube to work... and the only way I can see to do this is with a custom-made socket converter..... 

post #2524 of 5900
Quote:
Originally Posted by mordy View Post

Hi Edgard V,

 

I did not mention that I use a small high intensity CREE LED flashlight when the need arises to see clearly where to put those little straps.

 

Let me now how it goes with the straps.

 

Good luck,

 

 

Mordy
 

Ah, very good point, thanks again Mordy.  I'm hoping to order some of those IBM 6BE6 tubes at the end of the month, if not the EK90 Telefunkens (nostubestore claims to have Telefunkens in stock but they are on vacation until the end of the month).  Maybe some EF94s as well...

post #2525 of 5900

My resolve to avoid experimentation didn't hold and I ordered a ten pack of Soviet Cold War era mil-spec 6BE6 heptodes. Once sorted into matched pairs I'll install a set and compare these to the 6J1P-EV tubes currently gracing my LD III.

post #2526 of 5900
Quote:
Originally Posted by gibosi View Post

 

Do they have square getters? Or halo getters? My best guess: 935 + 1959, week 35, especially if they have square getters. Either way, I agree that these are relatively old, the 1950s and 60s.

 

And since they are "mine", I sure hope they sound better tomorrow! lol :)

Yes they have a square getter will have a listen again today they should sound similar to the other 6AV6 i guess hope your not disapointed lol.Like the old boxes dought ,never saw that style before and thanks for the dating    .on the flap i saw this H-4-59 thats probably the date.code  .                                                                                                                                                                                                                                                                               

post #2527 of 5900

i know most of y'all are heptoding at the present, but after trying a lot more tracks, types of music, the erricsons 408a really does improve the

mid bass of the ps500 !
 

post #2528 of 5900

Looks like the 6AN5 is a high heater current version of the standard EF95. Updated the table on p. 77 accordingly.

post #2529 of 5900
Quote:
Originally Posted by Acapella11 View Post

Looks like the 6AN5 is a high heater current version of the standard EF95. Updated the table on p. 77 accordingly.

Found a few more like the 6HA5 = EC900. 


Edited by siles1991 - 8/21/13 at 9:49pm
post #2530 of 5900
Quote:
Originally Posted by siles1991 View Post

Found a few more like the 6HA5 = EC900. 

 

Yes indeed, these triodes should work fine in the EF95 setting. This tube has only .18 amp heater current, which is a bit low compared to the .3 / .45 amp pentodes and heptodes we have been using recently, and I suspect that it will not play as loud. But still, .18 amp is about the same as the standard 6AK5 . The 6HM5 and 6HQ5 appear to be about the same.....

post #2531 of 5900

Just got the RCA DETOX (6DT6 ) in and went straight to the 1/7 strap and wow! I really like these! Sound stage is very spacious, bass is good maybe a touch loose, mids are good similar to the EH90 Valvo I have, the treble is a little lacking in sparkle BUT I assume something will change with burn in... these would be perfect with some sparkle!

post #2532 of 5900

Well gibosi your Westinghouse 6av6 are coming along nicely (24 hours)similar to the other 6av6 nice treble clean sounding tight bass nice crisp sounding good soundstage using the Senns hd800 and Conductor's Dac .                                                                                                                                                                                     

post #2533 of 5900

Hi kvtaco 17,

 

Glad to see that you enjoy the DETOX tubes. In my system these tubes sounded good out of the box, but started to blossom around the 25 hour mark. You will see that the bass gets more tight; don't know about the treble changing so much.  Everything becomes more, if u know what I mean, The mid range is very sweet, and the sound stage enormous. I listen through speakers, and I also have tone controls to adjust for different recordings and I can turn up the treble if needed.

 

There is a 6DT6A version as well, but I have not heard it yet.
 

post #2534 of 5900

ok, i must be doing something wrong, the seller that i bought the cbs hytron 6cs6 , sent me a set of rca  6cs6

they made an even worse noise than cbs tubes, a loud steady hum

the tubes construction appears a little different

i tried ef95 and 91/92 ,

i put the rca 5915's in, they sounded fine, so the amp seems ok, headphones ok

i double checked the jumper placements, and the 5915 is playing now

am i missing something ?

 

 

post #2535 of 5900
Quote:
Originally Posted by mordy View Post

Hi kvtaco 17,

 

Glad to see that you enjoy the DETOX tubes. In my system these tubes sounded good out of the box, but started to blossom around the 25 hour mark. You will see that the bass gets more tight; don't know about the treble changing so much.  Everything becomes more, if u know what I mean, The mid range is very sweet, and the sound stage enormous. I listen through speakers, and I also have tone controls to adjust for different recordings and I can turn up the treble if needed.

 

There is a 6DT6A version as well, but I have not heard it yet.
 


I tried them unstrapped and was meh... SO I made my straps permanent!

 

It was a super easy solder job!

 

I have the 6DT6A and its just as you described (I like my sparkle and as the bass tightens the treble comes out more) so far so good!


Edited by kvtaco17 - 8/22/13 at 5:43pm
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