Rolling With the Crack

[Yoder]

Last night I finally finished my Crack with the Speedball upgrade. Had a minor problem to contend with initially, but Eileen was great. Once I got the stereo back, I then lost a channel and spent about 5 hours Sunday trying to figure it all out. Slept on it, actually had dreams about it, and went to work on Monday. With my problem solving plan in place I pulled the A and B pads to thinking that I would take some voltage readings of the tube socket. Lo-and-behold, with my magnifying lens on I saw that one of the LED leads was touching one of the post that had 0 voltage. Moved it, fired the amp up and...Wow.

I put on a Ben Webster CD, The King of the Tenors, using a HHB CDR 850+ running through a Monster power filter, and my Sennheiser HD-650's, and was blown away by the audio quality. I did upgrade the tubes, RCA jacks (had a bad female that would not accept the male...a story all to familiar), and a GoldPoint attenuator. Oh, and to be cute I shielded the wires running from the attenuator to the jacks and grounded the shield...probably not necessary. To be honest, I have never heard such clear audio before. I had my wife come in and listen to the CD while I fired up a Lancaster flick (I Walk Alone.) An hour latter she was still listening with her eyes closed. Amazing sound there Doc.

I put some photos of it on http://www.co-bw.com. I did not use a calibrated monitor and so the red is not true to color and is more of an Gibson ES-335 red.

Anyway, it was a great project with sound quality far beyond what I was expecting. I am going to build some interconnects using some ETI Silver Bullets, and .9999% pure silver wire. I will do this as I patiently await the arrival of the BH DAC! I cannot even comprehend what the Crack will sound like once plugged into a quality DAC.

[dstrimbu]

Welcome to Bottlehead, Yoder. Your website looks awesome, BTW... definitely tagged for future reference!

Looks like you did a great job on the build.  You're right - I did not shield my input leads (but I did ask my wife to braid them for me - and she did a great job) and the amp is simply dead silent at idle.  Had a bit of right-channel hum with the stock 6080, but a NOS Sylvania 6AS7G knocked that right out of the picture.  I also upgraded the gain stage 12AU7 with a NOS Amperex Bugle Boy; the opportunities are near endless.

Only one issue with the Crack - listening thru my HD-600s, nothing else in the house sounds as good anymore.  :-)

Again, welcome!

-don

[tdogzthmn]

Only one issue with the Crack - listening thru my HD-600s, nothing else in the house sounds as good anymore.  :-)

Thats the same issue I have

[Yoder]

Welcome to Bottlehead, Yoder. Your website looks awesome, BTW... definitely tagged for future reference!

Looks like you did a great job on the build.  You're right - I did not shield my input leads (but I did ask my wife to braid them for me - and she did a great job) and the amp is simply dead silent at idle.  Had a bit of right-channel hum with the stock 6080, but a NOS Sylvania 6AS7G knocked that right out of the picture.  I also upgraded the gain stage 12AU7 with a NOS Amperex Bugle Boy; the opportunities are near endless.

Thanks. My site (http://www.co-bw.com) started as a place where I would post lessons for my students, but has since evolved into a reference site where I post the research/study I do for my various hobbies (DIY, guitar, Mac's, etc.) Hopefully, I will be retired by the end of this year of next year at the latest. Once that happens, then most of the computer tutorials will vanish and allow me to clean it up a bit. It is a bit intimidating as it sits now, but I am now getting over 1300 new hits a day.

It was interesting researching cables and shielding. I actually found a patent on braiding cables, but the link is at home in one of the many tabs I have open. Here are a couple of helix braids that have patents:

http://www.freepatentsonline.com/5831210.pdf
http://www.freepatentsonline.com/6242689.pdf

I am going to be using the first one to build my interconnects. Instead of doing the entire helix thing, I will be using the image in the middle and spiral the two leads over a piece of Teflon tubing--like VanHeaus does. Surely, patents of this type do not apply for non-commercial purposes? I will try to find the patent on the simple braid and post it. To be honest, I was a bit floored to see a patent on it. Surprised no one has put a patent on the pony tail yet.

[dstrimbu]

Surely, patents of this type do not apply for non-commercial purposes? I will try to find the patent on the simple braid and post it. To be honest, I was a bit floored to see a patent on it. Surprised no one has put a patent on the pony tail yet.

I believe that the patent is on the application of the braid - not the braiding technique itself.  And you are correct, you can leverage the design for non-commercial purposes, just don't try to sell a product that encompasses this technology.  Good finds here, the first one is especially applicable to some of the DIY projects that I've been considering.

I've been messing with different braiding schemes, leveraging multiple pairs of Cat5 wiring for speaker cables... a concept that's also from Chris VanHaus.  I wish I could get my hands on a decent LCR meter... maybe I'll head up to eBay.  I know that a cheap one is really cheap, but... I'd like something a bit more accurate than the $59 version.  :-)

Thanks again for sharing, Yoder.

-don

[Grainger49]

When one cable manufacturer came out with an "Active Shield" I perused the ads and reviews.  I figured out what was going on and then bought some Zipper-Tubing.  I attached a pigtail on each end and applied a DC voltage to the Zipper-Tubing from one end to the other.  I added a resistor, 1k per volt to get 1mA, and it made a difference.

Nice experiment, free and a tweak I will use again.