My corner of the web
Take a look at these EL-34’s from NessTone. I think they are OEM by Shuguang in China which I thought was a pretty good factory.
What is the brown stuff? It’s not getter, the top is nice and silver where the getter is. It looks like a burn on the glass but I don’t know from what or why. I have to on all 4 tubes. They run and sound fine. Bias is dead on. Are the tubes dying? Something else? I don’t have that happening on my JJ’s they are nice and clean. Weird…
Realized that it’s been awhile since I have put any computer content here. I have my home lab running perfectly with everything running on a cluster of Intel NUC’s and I don’t want to mess with anything. Decided to pick up 4 older small form factor computers to use as a Kubernetes cluster or whatever other project gets my attention next. I have already installed rhel and will start building it soon. I hope to to document some of the process as I go time dependent. I think it should be a fun project, not sure if it’s something I will keep running long term but want to install it and see what I can do.
Had to install a new AC in my moms room and then was planning to go to Long Island. Had some last minute changes so ended up back home. Put on some tunes and continued digging into my Audible Illusions project.
I remove the old capacitors, some of them really look like candy! Hard to find equivalents of some of them. I ended up putting back 4 of the orange drop caps because I was not able to find new ones rated at 800VDC. They test ok and from what I have read they tend to last unlike electrolytics.
I replaced the the big Mallory caps ( aluminum ones in the picture) with some super nice but way smaller in physical size AudioNote caps! I had some challenges getting them to fit since the Mallory’s were way larger in diameter but I was able to come up with a solution. I also had to go to the super old spec sheets to decode the polarity. The older caps used symbols not a simple positive or negative mark. Turns out the case is negative and the symbol(s) are positive.
AudioNote caps are a little bit expensive but I think this unicorn of an amp is worth it. And yes they are real, didn’t source them from e-bay. Got them from the Parts Connextion. The amp had a hard life in the past. Looks like it had a violent failure that took out some of the traces on the circuit board. I found it with some bodge wires. Very sloppy work. Here is what I did:
I also tried to make it less obvious with this attempt.
I think the second one looks more stock, if you don’t really inspect the board you can’t see it. Very happy with the results. When I got this amp it was covered in nicotine residue on the top and tons of flux residue on the bottom. Still have cleaning to do but it’s looking alot better. Maybe in the future I will get a bigger ultrasonic that can accept a fill size board. That would be alot easier then the IPA and q-tip method I have been using!
Going to start on the case and other bits and bobs next. I will get all the jacks and binding posts into my small ultrasonic to get the years of crud off. I also have to clean the bias meter, bias pots and tube selector switch. They need some TLC but nothing Deoxit can’t handle. Will post more when I can, for now happy listening!
Might have walked into a huge Record haul! Like thousands of them from the 70’s, 80’s and 90’s Going to Long Island this weekend with a friend to to take a look. Already have a temperature controlled storage locker secured. Fingers crossed it works out!
My latest audio acquisition is a Wiim Ultra. Lots of online audio influencers have been talking these things up and I wanted to check it out for myself. I was able go get it on-sale over at Amazon. I’m planning on doing a more thorough review but for now here are my list of of plus’s
It’s currently connected to to my nearfield rig using it’s built in DAC. In the near future I plan to test it with a few different external DAC’s to make sure it behaves as expected. Will update when I have more time on it. Right now it’s a shiny new thing to me and I want to really form a better opinion before I make any recommendations positive or negative.
I finally got him home! Not going to go crazy with this just one!
This happened a few weeks ago. I had just sat down to listen to my second reference system . I built it with some vintage but super high end gear. I powered up and gave the amps a few minuets to come up to temperature. Drop the stylus and after a few notes a horrendous scratchy static comes out at full volume! Like holy fucking shit volume! I immediately power down and notice smoke coming from the driver tube area on the power amp. Something seriously wrong just happened! I’m not exactly sure what but I do know it was bad. Since I’m still new at the repair hobby and because this amp is really nice I decided to take it to someone who’s worked on them before. I didn’t want to risk turning it into a doorstop and the voltages in it are frankly terrifying.
Just found out today the extent of the damage and I think I’m pretty lucky! The previous owner changed the fuse from a 2 amp to a 7 amp so it could have been really really bad. John the tech thinks that I might have accidently shorted out the leads and caused this shit show. 🙂 I can’t say for sure but it seems passable since I’m using spade lugs and not banana jacks on my speaker cables. The binding posts on this amp are also all metal making it even easier to cause this type of failure. John sent me pictures of the damage and it looks like I smoked a few parts in the driver section but its not that bad thankfully and fixable! It’s getting repaired now and I should have it back in two to three weeks.
John tested all the tubes and found that my power tubes tested pretty bad. Two of them are actually really really bad which has me a bit bummed out over. They are all relatively new PSVANE KT88’s. This is my first time dealing with Chinees tubes so I don’t know what I can expect in terms of life expectancy but I hoped for over a year. They did get good reviews online and I really loved the sound but I decided to order a new matched set of 8 Sovtek 6550we’s. I tried KT88’s and know the sound signature pretty well so now I’m excited to see what 6550’s will do to the sound and I know Russian tubes will last much longer.
Well that’s about all I have for today. Happy listening!
I built a bucking transformer for use with older tube amplifiers. Did you know that back in the day the voltage in the US was 110v! Yeah who knew! Its in the mid 120v range hovering around 123V-124V in my house in NJ. I have CT’s logging the power at my main breaker in my main panel so I have a log of this over time. This higher then design voltage takes it toll on old transformers and components. It can cause the bias voltages on the tubes to be higher and leads to tube wear and premature failure that I want to avoid. I can buy an off the shelf step down transformer or variac’s but they are expensive, big and ugly. It’s also no fun! I decided to go the DIY route and use a small 12v AC transformer to buck the voltage. The transformer I’m using is a $40 fairly cheap 12v center tapped one off Amazon. It’s not some exotic crazy expensive transformer hand wound by Franciscan monks with silver wire built somewhere in Europe. The trick is to wire the secondary out of phase with the input voltage on the primary. If you do this properly the two voltages will subtract from each other and you get the following:
If you wire it in phase you will get the opposite. The voltages will add together and you will get a higher voltage. This is called a boost transformer
This is a pretty neat trick and pretty cost effective. You don’t need such a big ass transformer because it’s not handling the full voltage of the load! Pretty cool right! If you would like to know more let me know and I can post pictures and a wiring diagram to help you build your own. I mounted it in a small metal project box I got off Amazon. IEC inlet on one side and regular household receptacle on the other side. I removed the tie on the hot side of the receptacle and wired it so that one plug is at 114V and the other is at 108 making it pretty versatile. I grounded and fused it as well for safety. I find it runs cool while powering a Dynaco ST-70 for hours.
Well time for bed. Happy building!
My girlfriend got me a Labubu! One of her vendors brought him from China. She opened the box with me on the phone so I know his color! 😬 He’s in LIC so I need to head over for the weekend and see. Love his toothy mouth and naughty grin like he’s gonna do something.
Hit another deer on the way home from Nutley Thursday. This is the second time with this car. First time was under 3k miles on the clock and this time it just turned 1 year old. Anyone want deer jerkey, burgers or hot dogs?! I’m getting my retribution this hunting season for sure. Going to work on getting my bow hunting skills in place this year so I have a longer season. Better watch your back Bambi… RJ and I are coming for you. 🙂