[jjhatfield]

Newb question: Whats the difference between a 5687 and a 5687 with the "WA" designation? (5687WA)

 

[sacd lover]

Quote:

Originally Posted by jjhatfield /img/forum/go_quote.gif Newb question: Whats the difference between a 5687 and a 5687 with the "WA" designation? (5687WA)

WA denotes the military version. But I dont see or hear any difference in the tubes .... they seem identical to any other consumer 5687 manufactured in the same time frame.

 

[budx3385]

"Stock" on this pre-owned PPX3 SLAM apparently were Philips ECG JAN 5687WB. The TS's improved on that greatly. I'm very happy with the RCA bronzeplates

 

[Amarok]

I've been using a 6414 in front of GE 6BL7GTAS as my favorite combo so far.

Last night, however, I decide to continue rolling and I tried an 8SN7 as a
gain tube. The result was nearly inaudible. I tried another 8SN7 with the same
6BL7GTAS and then with another set of 6BL7GTAS with the same results. Can
the BL7s be driven by *SN7s? Or is there some minimal gain required? Or
recommended? Can anything be damaged by under driving a tube?
What parameters from a tube's spec sheet can be used to determine the gain
required?

(To bring up my wiki idea again... while discussably (as opposed to arguably
unsuitable for subjective information, facts like gain, voltage, over
driving, etc do seem appropriate. And can hopefully prevent damage.
But the whole thing can be mooted if head-fi isn't interested in hosting such
a beast. Maybe SP might be interested in providing the b/w. I'd imagine the
initial setup of the wiki is pretty easy, but I have no idea how much admin
time they tend to need. I do know that SP have someone working on a new
website (although I don't know how much time or resources are being dedicated
to it. Or an ETA.) That may be a more appropriate place for the wiki, but I
don't know when it could be on line.)

Thanks very much for answering all of my newbie questions!

-=A=-

 

[budx3385]

augustwest, I'm through testing the 2c51 adapter and the TS tube that Mikhail sent me, so if you'd like to try it, pm me.

My SLAM has 5687 sockets in the output positions, so I can't try 6SN7s there, but I assume that SP made this amp because several people liked the "slam" of theses tubes for output. RS also uses these tubes in his Raptor. I do like the ones I've found.

I've compared my TS 6SN7GT again with the Amperex 1960s D-getter 6922 on the ECC-1 adapter as driver, and I certainly choose the latter for input. The 6SN7 is surely sweet, but IMHO the 6922 has less distortion on the highs, more dimensionality and depth, and gives my HD600s (Equinox) more emotion.

But I'm still not satisfied

of course. I went zooey and bought several different 6922 / 7308 tubes on eBay over the weekend to compare. I'm sad to say that I don't have a Mullard yet, RobN - I couldn't quite go for a single 7308 Mullard from Metcham for $175 "Buy it now" from an unknown Swiss dealer, and I couldn't talk him down.

After they have all arrived (some from Europe), I'll have a "6922 shootout"

 

[tkam]

Quote:

Originally Posted by Amarok /img/forum/go_quote.gif Last night, however, I decide to continue rolling and I tried an 8SN7 as a gain tube. The result was nearly inaudible. I tried another 8SN7 with the same 6BL7GTAS and then with another set of 6BL7GTAS with the same results. Can the BL7s be driven by *SN7s?

Why did you try a 8SN7? The SP amps are designed to run tubes with a heater voltage of 6V not 8V. 6SN7's can drive 6bl7 and 6bx7's just fine.

 

[Amarok]

My SP has a special circuit that automagically sets the heater voltage to
whatever is needed {12,8,6}v. I can't remember if they said that any thing
between 12-6v would work, too. It can mix and match voltages as needed.
Makes tube rolling quite a bit easier.
Anyway, I got 2 8SN7s with my order, so I just grabbed on of those.

If a 6SN7 can drive a 6BL7, then my 8 & 12 SN7s should too. I'll try with my
12SN7s later. I'll have to contact SP if these can't drive it either.

After some more reading, I thought it might've been a problem due to the
(slightly) lower gain of the BL7 vs the SN7 making a higher gain gain tube
like the 6414 necessary. The 6414 looks to have > 2x the gain of a SN7.

thanks,

-=A=-

 

[tkam]

Trying out a new tube tonight the 2C50 it's a low gain tube with an amplification factor of about 10. As you can see from the pic below it has rather odd looking plates. It uses an octal base and in my amp at least works fine as a drop-in replacement.

 

[Amarok]

Tried an Amperex 7119 (in the 5687 family) in front of some 6BL7GTAs and was
very pleased with the results. It was close to the 6414 but a tad smoother
in the highs. It seemed there was a little loss of detail up there, but I
may have just manufactured that sensation due to the extra smoothness. More
listening is called for. But I just got my T-S D-getters and want to try
them NOW!

-=A=-

 

[Amarok]

Quote:

Originally Posted by purk /img/forum/go_quote.gif Nope!! The tube is GE 12AY7A. This small tube fits in the 6414 adapter and has more natural presentation with warmer and full bodied sound than my Raytheon 6414. It also has similar bass response incomparison to the 6414. This is the first time Mikhail tried this tube with his amp.

Have you had a chance to listen to your 12AY7s with any 5687s yet? What
kind do you have. I ordered one GE and one Tung-Sol. I used 'em to drive
my new 5687 Tung-Sol D-Getter Black Plates (that flows trippingly off the
tongue). Thanks to the recommenders.
The short:
GE 12AY7 + TS D-getter black plate 5687s: great.

TS 12AY7 + TSGDBP 5687s: Transcendent.

...

The TSDGBPs are so much better than the Sylvanias. In fact, the stock
SLAM type tubes made the sound border-line "return the amp." I do not
fault SP AT ALL for this, since SQ is soooo subjective. Fortunately, I'd
been emailing with J Petrie and he mentioned some of the combos that
they were listening to there and thought sounded great. I tried one of those
first and it was love at first listen. And it's gotten better. A few
disappointments, but mostly positive. Other tubes that came with my amp
gave me the best sound I'd heard up to that point in my music addiction.
Driving the TSDGBPs the GE 12AY7 was a new high.
But driving them with the Tung-Sol 12AY7s made that sound like a WalMart
"rack" system. When listening to one of my bench mark albums (Mike
Oldfield's Amarok) it was like someone had remixed it, bringing all kinds of
new and interesting instrumentation out of the "darkness." I noticed all
kinds of timbral differences, harmonic structures, especially in the
instrumental decays. I was amazed. It was almost like the sound was
being compressed, bringing all sorts of information into audibility. Amarok
is quite complex and well recorded and it really came though. This combo,
sadly, didn't do very well with the overly bright 70s prog albums I love.
Fortunately I've found other combos that do make those albums sound
wonderful. So, it looks like frequent tube swapping, for plain listening as
well as for rolling, is in my future. Tube rolling is the ultimate tone control.
I've looked all over for the socket savers sacd-lover mentioned, but the
only ones I've seen are for nonal sockets. A few places sold some pieces
that could be made into savers, but my soldering skills are a clear and
present danger to all around me. If anyone has any info about finding
some, I'd really appreciate it!

So I'm off to buy 100 TS 12AY7s and 200 TSDGBPs.

Maybe I'll try a few TS Bronze plates, too. The bronze'll go better with our
decor

 

[Amarok]

Quote:

Originally Posted by budx3385 /img/forum/go_quote.gif My SLAM has 5687 sockets in the output positions, so I can't try 6SN7s there, but I assume that SP made this amp because several people liked the "slam" of theses tubes for output. RS also uses these tubes in his Raptor. I do like the ones I've found.

My 5687 adapters are removable, and the underlying socket is the original
6SN7 socket. Have you tried removing them?

-=A=-

 

[sacd lover]

Quote:

Originally Posted by Amarok /img/forum/go_quote.gif My 5687 adapters are removable, and the underlying socket is the original 6SN7 socket. Have you tried removing them? -=A=-

He is saying his amp has 9 pin mini sockets wired for 5687's. Some amps only take the 5687 and the 5687's variants.

 

[Amarok]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif He is saying his amp has 9 pin mini sockets wired for 5687's. Some amps only take the 5687 and the 5687's variants.

Is this for reasons other than socketing?
Could adapters from nonal-5687 to octal-??? be made?
The new sonic signatures the adapters open up are so valuable.
I'll probably be buying adapters for years.

-=A=-

 

[Deuterium]

Rolled tubes for the first time last night. I am sure this has been discussed many times, but what is a reasonable amount of burn in on tubes to approximate equilibrium?

 

[Jahvetti]

Quote:

Originally Posted by Deuterium /img/forum/go_quote.gif Rolled tubes for the first time last night. I am sure this has been discussed many times, but what is a reasonable amount of burn in on tubes to approximate equilibrium?

For brand new tubes I would guess some 10 hours. They might evolve after that still, but if they are working properly, the change should not be too large. However, I have no experience in those extreme tubes.