[JamieMcC]

I found a magnifying glass very helpful for checking on my soldering of all the through hole components.

 

[MattTCG]

I spent the last week going through my library of test tracks and really putting the crack through it's paces on the hd650. Here are a few things to share:
 
1. The 5998 is going no where and is my favorite of all the tubes I've tried. 
 
2. There is a sense of naturalness in the tone of music that is simply sublime. The resounding pluck of an acoustic guitar string, the satisfying thump of a kickdrum, the emotional wail from a violin...just wonderfully realistic. And of course both male and female vocals are wonderfully reproduced. 
 
3. The only setup that has bested the crack/650 for me in terms of realism of tone is the Stax sr007 mki on the BHSE. And that's pretty good company to keep IMO. 
 
I'll dub the crack/650 the poor man's Stax rig. 

 

[NightFlight]

Hmm. Here I was thinking my rig was entry level. Hoping for lots of upward scale with electrostatics.... I'm determined to try the 009 on the BHSE and see if its worth the fuss. Well, hemorrhaging wallet.
 
I sometimes miss my Lyr with the Siemens CCa and HD800s driven by the Uber DAC. It's damn fine too. Wishing I kept it for reference. Need a WE 421A?

 

[NightFlight]

I recently bought Chatham/TS 5998 from a fellow Head-fier and ordered a Tesla ECC802S from Ebay. How long does it take to burn them in? I have a Crack Amp with no speedball upgrade yet. 

20-100 hrs

 

[bigfatpaulie]

I am so jealous of all you TS 5998 owners.  I've been through THREE of them and not has worked for me.

 

[ben_r_]

  I am so jealous of all you TS 5998 owners.  I've been through THREE of them and not has worked for me.

You have?! I have three that have worked fine through my testing. Though I only use one. The other two have just been sitting in my closet. What has been wrong with the ones youve had that didnt work?

 

[MattTCG]

I would guess that they are microphonic.

 

[bigfatpaulie]

Static or interference of some kind.  I can't recall what was wrong with the first one, but it was un-listenable. One just buzzed out of the right channel and the third one gets a rustling sound on one side.  Brush your finger on your ear hole (I know, ha ha....)  and that's the sound it makes.  The third one is the best one I've found so far.  At first it seemed to only do it with one tube and worked fine with everything else.  Now it does it with everything.  Because it worked (sorta) at the beginning, I ended up getting stuck with it.  So it sits on my desk and looks cool.

 

[ben_r_]

  Static or interference of some kind.  I can't recall what was wrong with the first one, but it was un-listenable. One just buzzed out of the right channel and the third one gets a rustling sound on one side.  Brush your finger on your ear hole (I know, ha ha....)  and that's the sound it makes.  The third one is the best one I've found so far.  At first it seemed to only do it with one tube and worked fine with everything else.  Now it does it with everything.  Because it worked (sorta) at the beginning, I ended up getting stuck with it.  So it sits on my desk and looks cool.

Dang, that sucks man, have you tried buying from these guys brand new: LINK Right on their front page they say they have Tung Sol / Chatham 5998's for $85. I got one of mine from them.

 

[bigfatpaulie]

Yeah, I'm pretty disappointed about it.  One was EBAY and two were from folks around here.  I could never find them NOS for sale.  It's a shame too.  I think my Crack is reaching retirement now, however.  Thanks for the link - I may take the plunge (yet again) and grab one while they are hot.

 

[ben_r_]

  Yeah, I'm pretty disappointed about it.  One was EBAY and two were from folks around here.  I could never find them NOS for sale.  It's a shame too.  I think my Crack is reaching retirement now, however.  Thanks for the link - I may take the plunge (yet again) and grab one while they are hot.

Yea VaccuumTubes.net usually has them in stock and they are brand new. Give them a try and sell your others for whatever you can get considering their condition.

 

[bigfatpaulie]

Thanks.  I'll give it a go.
 
...
 
...
 
Wanna buy a semi-working 5998?  I kid!

 

[FlySweep]

  Received some new candles today and I'm just blown away how good 6085 E80CC/Amperex (PQ) is ,I have vintage 6922 and Bugle Boy Treble Clef ecc88 but this was unexpected ,it brought a lot of clean/sparkly highs to my 650s and the bass is just hard to explain ...highly recommend this tubes 

P.S. thanks Jamie for  E80CC recommendation

 

 
Ahh.. the Amperex 6085 is a terrific tube.  I think it's a perfect complement to the Tungsram E80CC.  The 6085 develops a midrange that's to die for... to die for.  Smooth, rich, warm.. but airy and wonderfully detailed.  I wouldn't have thought this type of sound would work with the HD650's signature/tuning.. but it does!
 
I've always liked how E80CC/12BH7s have sounded in the Crack.. whether it's with the HD600 or 650.. but I far prefer rolling E80CC/12BH7s with the HD650.  The 600 impressed with them, but it was more of something I'd marvel at.. but not really enjoy, long term, when it came to music.  The 650 enables me to marvel at their performance and I find the 650 synergizes with them better (12BH7s tend to sound a bit forward).  The 650 also reveals the 12BH7's technical abilities better (bass performance, imaging, soundstage, and treble detail) than the 600 is capable of, IME.

 

[NightFlight]

Static or interference of some kind.  I can't recall what was wrong with the first one, but it was un-listenable. One just buzzed out of the right channel and the third one gets a rustling sound on one side.  Brush your finger on your ear hole (I know, ha ha....)  and that's the sound it makes.  The third one is the best one I've found so far.  At first it seemed to only do it with one tube and worked fine with everything else.  Now it does it with everything.  Because it worked (sorta) at the beginning, I ended up getting stuck with it.  So it sits on my desk and looks cool.

 
It is one of a few things:
 

1. oxidization on the tube pins
2. octal socket tolerance issue with 5998
3. oxidization on the 5998 pins
4. electrical issue - voltages

 
There are a number of troubleshooting avenues here. You could clean out the socket and clean tube pins. My money is there because of nature of the sound your describing. I get that with new tubes all the time. I used to use 1000 grit sandpaper and alcohol. But now I use deoxit cleaner with cotton pads.  Also after I had my pins all cleaned up I had to clean out the sockets with some deoxit, which wasn't as easy. A pipecleaner with deoxit or contact cleaner if you can't get your hands on deoxit might work.  I've never been able to not clear up that random rushing sound with cleaning... but it can be electrical as well - though more unlikely.
   
If you know someone with a crack, you could test the 5998 in their crack. Or ship it to a head-fier you know and trust.
Maybe there's nothing wrong with the tubes and your octal socket is super picky or needs cleaning or even replacing. 
 
Consider the above, the 5998 IMHO is worth it - Or I just lucked out with  my '57 Tung-Sol. It rocks.

 

[NightFlight]

   
Ahh.. the Amperex 6085 is a terrific tube.  I think it's a perfect complement to the Tungsram E80CC.  The 6085 develops a midrange that's to die for... to die for.  Smooth, rich, warm.. but airy and wonderfully detailed.  I wouldn't have thought this type of sound would work with the HD650's signature/tuning.. but it does!
 
I've always liked how E80CC/12BH7s have sounded in the Crack.. whether it's with the HD600 or 650.. but I far prefer rolling E80CC/12BH7s with the HD650.  The 600 impressed with them, but it was more of something I'd marvel at.. but not really enjoy, long term, when it came to music.  The 650 enables me to marvel at their performance and I find the 650 synergizes with them better (12BH7s tend to sound a bit forward).  The 650 also reveals the 12BH7's technical abilities better (bass performance, imaging, soundstage, and treble detail) than the 600 is capable of, IME.

 
The one 12BH7 that randomly came my way and I tried has a "Rogers" Canadian re-label I think. It sounds nice, but a bit muddied up I realized after the initial warm and fuzzies wore off. With the muddy presentation the magic headphones are capable of is missing.  Perhaps a bit too much gain I think. I seem to prefer a slightly warm of neutral, punchy, technical tube that can show off a soundstage where layering is realized. These days if a new tube hasn't got that sort of potential, I move on. 
 
I've been eyeballing the Tesla 802S and various E80CC on here. I've yet to settle on make and year for a purchase. Any suggestions?