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Crack;Bottlehead OTL - Page 338

post #5056 of 8350
Originally Posted by ModestMeowth View Post

Hopefully it isn't as microphonic as the last two I received from them :basshead:

I just got my 5998 from them this morning and it's fine -- very very slight microphony but perfectly acceptable in a headphone amp and only perceptible if I bash the desk... which I'm not in the habit of doing :)




PS My first post! Been reading for ages but never posted before.

post #5057 of 8350

^^ Congrats on the first post and welcome. I hope that I have as much luck as you with the TS5998. They have become a rare bird indeed. I believe that this is referred to as the head-fi effect. :wink:

post #5058 of 8350
Originally Posted by grrraymond View Post


Also, anyone got any thoughts on choking the PSU? :)



And I've just stumped up for that GEC Brown Base on eBay UK. Looking forward to comparing with the TS5998.


Graham l really hope you enjoy the GEC, I posted it first thing this morning 1st class. I originally purchased it as tested strong and have only used it sparingly rotating its usage with my other GEC's & 5998 tubes. I'm looking forward to hearing your impression of it with those Mundorfs.


I was pleased with the results from choking the psu and replacing the last electrolytic with a film cap. Dynamics, bass, and venue acoustics on live recording stood out as the most noticeable areas that benefitted from the mod along with a blacker background.


The guys on the bh forum walked me through the mod. 



Edited by JamieMcC - 5/20/14 at 9:21am
post #5059 of 8350

Thanks for that, Jamie. That's sooner than I'd expected. I'm really looking forward to it. Will post up impressions as they develop.


I'll have a more detailed read of the choke mod too, it seems more straightforward than I'd expected.


I must say, this is one of the best projects I've gotten into for a good few years. Really enjoying myself.

post #5060 of 8350

Here are some figures for the choke Mod.


I used to 2 Short U-Shaped Brackets mounted back to back to mount the choke on £4-5 delivered


Triad C7X 10H 90mA smoothing choke £16-£20 delivered


Film cap plenty to choose from suit all budgets cheap motor runs or premium audio caps


5x Small bolts, nuts washers to mount the choke and U brackets, a couple of pounds.


One of the things to bear in mind is ground clearance if you use a big film cap.

post #5061 of 8350

I have the ts5998 due in tomorrow from vacuumtubes.net  Hoping that I have a noise free tube!!

post #5062 of 8350
Crack + Submissive = Win!

Clarity and speed.

Cap upgrade (Obbligato Gold) also helping.

RCA clear top up front with TS 7236 in pride of place up the back.

post #5063 of 8350

how is the crack pair with schiit modi? 

and i understand that i need 3 cables right?

2 rca to rca 

and one usb to mini usb?


give some tips for good cables thnx exept blue jeans because the shipping expensive..

post #5064 of 8350

Thanks, so it seems like a perfectly affordable and quite fun mod. I think the biggest challenge will be space and fit.


I'm still burning in these Mundorfs so will give it a little while to see how these change before taking the next step.


Obviously, I'll be rolling in that GEC first thing!

post #5065 of 8350
Just bought 8 x Tung Sol 7236 tubes that had been relabelled (incorrectly) as 5998A's by Sylvania. All eight sound stunning and most test new. I think I'm set for life!
post #5066 of 8350
Originally Posted by MoatsArt View Post

Just bought 8 x Tung Sol 7236 tubes that had been relabelled (incorrectly) as 5998A's by Sylvania. All eight sound stunning and most test new. I think I'm set for life!


Dang, nice find!! Today I'll be setup again on my favorite chain. uberfrost>quickie>crack>650. :D

post #5067 of 8350

Latest caps rolled in the Crack.


A pair of pre-loved EPCOS (Siemens) 750v100uf polypropylene in oil films (non audio caps).


These are very nice sounding caps imho and seem to be the equal to any of the audio branded mkp films I have tried to date while also providing that liquid effortlessness in presentation that only the pio's can do yet combined with plenty of details and rich smooth vocals.


I later tried bypassing them with a pair of Hovland Supercaps 1uf/400vdc with good effect. Increased detail and clarity a sense of intimacy in vocal presentation with some familiar tracks. With the Hovland's added the presentation also felt slightly faster than that of Epcos PIO's on their own. 



Edited by JamieMcC - 5/21/14 at 5:30am
post #5068 of 8350

^^ You are truly a mad scientist sir. In the best way. :D

post #5069 of 8350
Originally Posted by JamieMcC View Post




This is truly beyond my level.

post #5070 of 8350

They turned out to be smaller than what I initially thought at about 120mm x 60mm not including the fixing stud which sticks out about 10-15mm from the base with a bit of shoe horning I think these will fit in the Cracks enclosure I just checked they are a tad smaller than the Obbligato Film Oils which are 65mm diameter x 135mm so should fit. 


I have just connected them externally with fly leads at the moment. 

Edited by JamieMcC - 5/21/14 at 5:31am
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