|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
76.90.36.216
In Reply to: RE: RCA 5691 Vacuum Tube posted by tlowe on July 22, 2021 at 10:33:35
I don't know the answer to your question. I got out my three RCA NOS 5691s in military boxes and none of them show the discoloration of the getter flashing.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Follow Ups:
Mine are as Tre described.
The 5691 and 5692 are RCA military tubes-- 5691 is a
6SL7 AND 5692 is a 6SN7.
While these are a solid lasting tube, they
don't perform in audio very well.
The later RCA and G.E. models that are all
glass, with only a thin wafer as the base,
greatly outperform the Mil-Spec variety.
-Dennis-
I find the "coin" base tubes to be some of the worse sounding tubes I own.
BTW Telling people that a 5691 is a 6sl7 without informing them that it draws twice the heater current is somewhat irresponsible. Maybe you didn't know that and maybe that's why they didn't perform well for you?
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Gosh! Heater is .3 amps in one, and
.6 amps in the other. Both need 6.3 volts.Now, if the filament supply is robust,
it will provide the 6.3 volts at either
load, so in a device that can (should)
provide 6.3 volts for either tube, then
no problem.When I compared the tubes to each other
(sonically), the 6SL7 filament voltage
was 6.4 V.A.C., the 5691 filament setup
was at 6.35 V.A.C., so I deduced that difference
not to be a problem. In any case, I was discussing the
sonic characteristics. If one is using an inferior filament
supply, it might not like a different load as you point out.Von Gaylord had also used those coin-base tubes in his amps.
The RCA 5691 was better than other brands of it.
This robust industrial tube had plenty of drive,
really good bass, and a clean mid-range, but it just
couldn't convey a musician's artistic intentions
like the designed-for-audio tube can.The large bases of the non-coin base tubes sonically
(mechanically) shunt-out the really good highs.The coin-based models do not have this DEFECTIVE BASE.
The coin-basers reproduce far more of the high
frequencies. Equipment that exhibits some distortion
in the highs will benefit from a tube-base that knocks-out
some of the H.F. musical information.-Dennis-
Edits: 08/12/21 08/12/21
Whoa!!! I didnt know that, really good to know. Thank you for the info, greatly appreciated.
You're welcome.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 07/27/21
Others might disagree but I agree that they are not really as magical as others have exaggerated on the sound. They somehow give me an impression of "short breath" on the vocals, especially with Jazz, Blues, Ballad, etc... Same as the Tung-Sol 6SU7GTY, which I dont realy like either, I think these tubes are more suitable for rock, metal, pop, etc...more aggressive music. I have tried these tubes on rock, metal, pop...and they do sounded more lively and fast compared to tubes like Mullard ECC35.
The 5691 draws twice the heater current as a 6sl7 and in some heater power supply designs this will cause major problems.
Were you taking that into account?
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Thank you for the advise, appreciated.
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: