Wednesday, June 30, 2010

Scale...

Let's see if I can get this one to convey via the computer. In person, it is hilarious.


One of the big projects I am working on is finally getting to build the 304TL properly. As you guys know, I have been working with this tube for years and years now. It really is so transparent and big and incisive, that it sounds like the parts you surround it with. In that manner, it is like cooking tofu. And you guys know how I like tofu. I liked it best with a single triode stacked supply direct coupled driver with the Altec 15's. Let's call that the family favorite tofu tacos. With the big horns I liked the sweet and detailed 485 transformer coupled. So how about calling that a tasty Indian Masala?


What I am now working on is the Thai green curry tofu version of the 304tl. Throw everything I can at it. Real power. Big sound. Make music. So you will note that what I am actually listening to is the driver stage for said amplifier. His speakers are more than 10dB less efficient than mine, so his driver stage will easily power my speakers. What is missing in the above picture is the Aa on the left. That is the best input stage so far. The output here, which will be the driver in a few days, is the Western Electric 205. I know why people pay what they do for these tubes. Fabulous sound. Resolution.

So what I have been doing the last few days is flipping from the cobalt parallel feed arrangement, to 80% nickel, to the amorphous quadruple C-cores. And just listening.. for flavor.. so let's see if scale comes across... I am going from the first picture above, to the one below:



and from that, to this:


and believe it or not, they all have roughly the same inductance, just wildly varying dc current capability....

Scale.... it is all relative...

Saturday, June 26, 2010

Earthquake Research?

I met a local DIY'er. For most of you, this is a normal event. Here in the deep South, this is an extremely rare event. Danny is a super nice guy. Pure hobby for him. He has a great attitude. He isn't trying to pursue the extremes. He is having fun. Lots of fun. He has a few toy rooms. And a nice garage shop. He even has a site up with a few of the things he has played with/built/rebuilt.

He found me and asked if I wanted this amp with Eimac tubes in it. I bet it took a half second before I said yes. I love just seeing these old things. To get to dissect one is heaven. (I know, I am a geek). When I walked up, this is how I saw it sitting:


So you are thinking what I was thinking - top deck of a transmitter, right? Well, no. He tells me it is an audio amp. GULP. And then he says it was the DRIVER STAGE! I am now running all kinds of numbers in my head.


Yep, water cooled triodes as outputs. Output transformer was a square yard. yes, EU friends, a cubic meter. He said it produced nearly 10,000 watts at very low frequency. This is at odds with the laws of physics. High power and tubes should never be ultra *low* frequency. Then he finally brought out the final clue. It was from the University of Memphis branch of the Earthquake Research Center. Dude. This thing is seriously cool.


Coupling cap anyone? This is a nice 0.1uF Sangamo oil cap. Perfect for coupling, except for the fitting it under the chassis. 7500V. If the guys on Audio Asylum think that the higher voltage rated caps sound better, then this is among the finest coupling caps out there. (You are supposed to be laughing). The cute little Bugle Boy 7119 is for size reference. Just like the Radian driver in my last post.


Oh! He also had the rectifier deck. This is pretty cool, too. That is a serious chunk of phenolic. Half inch thick. I am going to assume three phase power to this monster. I will definitely use this somewhere.

Thanks, Danny... and now we almost have enough for a group get-together.... almost...

Peace,
Me

Friday, June 25, 2010

third bass

Let me be clear up front that like the warning on this cover and what follows may be offensive to some readers... the kids however loved it.


Even though the Little League season is officially over and the older boy went 2-11, I consider it a victory since at one point they were facing 0-11. In any event they came on strong in the end. Oddly enough I think vinyl and 3rd bass actually had something to do with the late season surge. (what follows is a re-creation and the albums have been changed to protect the albums destroyed)


Essentially the team had a practice in a park without a diamond and given the inability to herd squirrels on a properly formatted field, I took it upon myself to bring some bases. First thought was to borrow the little rubber bases. Second thought was to simply cut some 12 X 12 pieces of wood. Third thought was the most obvious and take some cull records.

There were 10 kids on the team and at the time I was amazed that only two knew what I had placed as bases. It was when they realized they could jump on them and break them the other 8 suddenly ran with passion to destroy that evil copy of mantovani.

Did this have anything to do with them winning the next two games? I don't care. Is the world a worse place because the records were destroyed? I don't care. The fact that now all 10 kids on the team know what a record is and the fact that they won two of the three following games is enough for me.

Wednesday, June 23, 2010

So what should I do with.....

these compression drivers that just found their way to me?


They are even larger than they look. The voice coil diameter is six inches. The overall diaphragm is larger than a Lowther. Preliminary measurements say that the low frequency ability will be basically limited by the horn. Do I get out my old horn extensions that I used for the JBL 2482 and drive them down to 60 Hz? Do I whip up a field coil and convert them first just to get rid of the "ceramic sputter"?? If I only use them up to 200 cycles, then does it matter how the ceramic sounds? I dunno...

I am sure they will be slapped onto a horn soon enough just to evaluate for potential. ...kinda like dave was in Lisa's post below... I am thinking the same will result... we can make these into something with only some time and effort.. :^)



They are here on long term loan... but I bet a field coil will happen rather quickly, don't ya' think?

Sunday, June 20, 2010

The Hustlers


I have always loved this picture from the movie. How so much emotion can be struck from a single image still amazes me. Below is a quick snap of another image from that era that really caught my eye when I first saw it hanging on a wall 10 months ago. Somehow, when I saw this picture, I felt like I was there and something meaningful had happened.


While I don't have all of the actual dates and times of when the event happened, the actual event being celebrated was the completion of the model 10 by Dick and Sid. Dick explained the picture to me when I first saw it and I believe it was single malt in the cups. To this day I am still eerily attached to it so I asked Dick if I could take a quick snap of it to show my friends.

The more I look at the two pictures, the more I am beginning to think that my initial attaching of these two images had something to do with my belief that Jackie Gleason was is in both and somehow the marantz designers were the rock stars of their generation. The connection of Sid and Dick to Jackie and Paul was a silly one until I found out that Sid actually came to New York to pursue singing and a life on stage and became an engineer to fund that passion. As education goes, beyond his stint in the army Dick is completely self taught on his passions.

Today when I look at those pictures, I see 4 artists with true passion and happy memories of a lost friend.



Saturday, June 19, 2010

A piece of audio history.


What resides in this box is a true piece of audio history that was once owned by Sid Smith. Sids widow had a flood in her basement and my friend Ijaz went up to help her clean things out. In his sifting through the waterlogged items he stumbled across this case and what was inside was a far more valuable artifact than the watch it once housed.


In true Sid Smith style his own personal hand-built gaussmeter was recessed into a piece of walnut.


Today Ijaz and I went down to see Dick Sequerra and took this meter in tow to try to decipher how / if it still works. Dick has a bell 610 meter and a 5Kgauss standard and a magnet that measures 10Kg. A few minutes later the meter was giving us values that matched his 610 so I'm reasonably confident that it still is still functioning properly.

Here is a closeup of the only documentation we have on the unit and interestingly enough, it is all we needed to get it working.


The procedure is install a AA battery and plug the jacks into a DC voltmeter. Flip the switch to Calibrate and adjust to .768V Flip the witch to measure and 100mv is equal to 10Kg.

I'll compare it to my probe later in the week and tell some more tales of the trip but this one has me as giddy as a teenage girl at a slumber party.

dave

Thursday, June 17, 2010

recoil.

By now many of you have seen this picture of Bob Carver floating around the net.


Rather than make my own comments I'll just point you to this DIY Audio Thread and show you all a picture of me in action in my much smaller corner where I wind.


In order to take this self portrait I needed to somehow support the camera and aim it. I tried various methods. The 75TL was too round, the 2A3 too irregular but a Cunningham CX-112A on top of a 10 pound spool of wire or two was just right.


I chose recoil for the title since that was what I was doing. I was REwinding COILS for the Lowther Field Coils. One of them took a severe hit on its way to the reviewer and the coil was damaged.

This is a closeup of the mandrel about 1/3 the way wound.

The last row of wire is on.


10 pounds of wire standing proud.



All that is left to do now is make them ugly again by sealing them off with tape to protect the magnet wire enamel and installing them in their new home for the next 50+ years.

dave

Western Electric RIAA Corrector...

I finally uploaded a new page with some pictures to the Experience Music website...

A few higher resolution shots below:


I really like the sound. I am sure a large portion is due to the WE101 output stage - a genuine directly heated triode in a phono stage. Very transparent.



Subtle glow:


Peace,
Me

Tuesday, June 15, 2010

one of the boys turned 8 last Saturday.

Just over a year ago before he turned 7, I asked my oldest what he wanted for his birthday and he simply replied "A stereo like yours". Being the smart adult, I quickly responded you are too young for that type of responsibility and you will have to wait. He quickly rebuffed "How long?". In my brilliance I said "when you are 8".

You will notice that my last post was a full week ago and in my defense the question came from my then 7 year old pachyderm "How is my stereo coming?"

Saturday afternoon this was tossed in the trunk of the car with a bunch of cull records and after a visit to an arcade with his friends, I told him I was going to the transfer station (PC for dump) with some junk. He refuses to throw anything away and became alarmed what treasures of his I might be tossing. When the trunk opened he realized it was his stereo and his friends couldn't figure out his enjoyment from the junk.


Prior to giving it to him, the right channel of the cartridge was gone so the left channel served mono duty. The cantilever (of the removable stylus) looked like this. (funny thing is the sound wasn't bad)


He was so happy that there was actually the option to play a 45 since his favorite record from his collection of three given to him by our DJ friend Leith just happened to have too big of a hole and needs too fast of a rotation for "daddy's turntable".


In case any of you want to know what type of music this is, I'll test the blogs video capabilities and show you the previously unreleased 2008 bootleg video.

video

In the defense of the proud slagle name, he was 6 and his brother 4 when this was taken and in case you haven't noticed, we are hopelessly pale. (PC for white) The good news is three weeks ago his aunt lent him an ipod and for a moment, that is all he wanted for his birthday, so if all else fails, I successfully quashed that idea.

Knowing him the way I do, in a few weeks he will ask me where his tube amp is thinking it was part of the deal. Thinking I can outsmart him, I'll say "You get a tube amp when you are 9".

Do any of us ever Learn that our children are truly smarter than us?

dave

Monday, June 14, 2010

Carbon Plate?

Wow... You get new and crazy things every day from eBay. I buy a lot of the older small to medium sized transmitting tubes. I think they are genuine bargains lost in a world of high dollar 12AX7's. Most are directly heated triodes, my favorite style of tube. The real cost of using these babies is in the associated iron. Luckily, I know a guy who can wind that for me (wink!), so I keep buying all these strange old oddballs.


I have purchased quite a few of these 834's over the years. Some have fins. Make that some have one fin, some have two fins, some have three. Several different manufacturers made them. They aren't plentiful, but they also are not in demand. It is just a good old triode. I like 'em. I like 'em a lot. I guess I first fired one up in Class A1 about five years ago. Here is an old picture with a 15E driver.


Notice that the plate is a dull grey color. Definitely a metal plate. All of my tubes have been metal plates up to this point. I recall looking at the RCA Transmitting Tubes manual and thinking that the plate was drawn as carbon, but until a few days ago, I had never seen one.


See how the 800 is drawn as a metal plate? The 834 is clearly drawn as carbon. Very black. So now how the heck do I find a mate? Oh, I know. Just like all the others. I will wait ten more years on eBay.

I guess it would be mean to not show one lit up. So here you go:



[to all the well-wishers: Thank you for your concern and good thoughts. I am back up to full speed. It wasn't fun. I hadn't eaten for too many days and was running a crazy fever. But I am well again. I've been soldering and clip-leading like my old self for two or three days now. Woo hoo!]

Friday, June 11, 2010

Potential

My grandfather was a very wise man, a man who managed to stay happily married to my beautiful and smart grandmother for more than 60 years. Since Jeffrey and I got married at the age of 13 (which made us legal in the great state of Tennessee), we were often able to benefit from his advice. One afternoon, my grandfather pulled me aside and spoke these words of wisdom to me. “You know, sweetheart, when a young man falls in love with a woman, it’s because he looks at that girl and sees so much to love about her that he knows that he wants to spend the rest of his life with her. When a young woman falls in love with a man, it’s because she sees potential. Then, she’ll spend the next 60 years trying to change that young man into what she believes he can become. Sometimes, baby doll, you just have to let him be who he is.”

And while I am still guilty of trying to change him, I often reflect on that advice in the moments when it is really painful just to let Jeffrey be who he is…


While Jeffrey was in Dallas for the most recent show, I was standing outside with all of my children, and a man that I didn’t recognize pulled into our driveway in his convertible LeBaron. He was sporting a United States flag bandana around his head and a matching sweatband on his right arm. He had on mirrored Kanye West sunglasses and a blue ringer tee with an Eagle on it, and I swear that even though I knew that it couldn’t possibly be my husband, I actually did a double take. This man literally had Jeffrey Jackson’s hair… from the cut all the way down to the gray hairs sprinkled in that Jeffrey claims are blonde highlights! I wasn’t sure if perhaps this was some sort of a joke.


As the man drew closer, I realized that it was a good friend of Jeffrey’s from a long time ago. Clay was in town visiting family, and I really enjoyed catching up on his life. He explained that because he has his own business, he is able to live part-time in Colorado and part-time in California. Clay is a wonderful guy, so, of course, I was glad to hear that he was able to live his own dream and make a living by doing the thing that he loves to do.

I mean how many people actually get to put the word “Inspirationalist” on their business cards?

As Clay was pulling away, our fifteen year old son looked at me and said, “You know who that is, don’t you? That’s Dad without you.” Truer words have never been spoken…

Dave Slagle, on the other hand, has the benefit of living the bachelor life with his two precious boys. (See pictures of his home in his recent post below.) He’s got no limits… no one holding him back from being all of the Dave that he can be. Dave can just go right out into the world and be an Inspirationalist!

Sometimes, Dave’s freedom hurts my ability to rein Jeffrey in when he and Dave have one of their brilliant late-night ideas. Sometimes, Dave’s freedom gives Jeffrey the crazy thought that he can go even further off the map that I have tried so desperately to keep him on.

So, now, I’m on a quest. All I’m saying is, girls, I think that Dave has a lot of potential…

Lisa

Tuesday, June 8, 2010

You might be a Junkie If:

Spring Cleaning leaves the top shelf of your Clothes Closet looking like this.


The Waiting to be cleaned vinyl starts to overtake the perimeter of your rooms.


What once held important papers now overflows with listening options of the day.


You actually consider buying this off ebay with hopes that the tube is good.


I could keep going but you get the point.

dave

Saturday, June 5, 2010

Evil Mercury....

I never thought I would type that... but I have finally found evil mercury. Nope, it hasn't magically jumped through the glass of my rectifiers, despite public claims of such nonsense. It is the mercury in that blasted thermometer. Every six hours or so it ramps up and I get cranky and can't think straight.


I have been cheating it a bit, though. Working on things during the magic Advil window. Yes, I have been resting, too, but look what I packed and shipped yesterday:


Sadly, that is about all I got done, but it is on the way. With any luck it will be spinning vinyl at Capital Audio Fest. (Dave, do you know why you got that wicked loud hum when we hooked it up (at 3am) in dallas? Apparently it helps to connect the input to the grid instead of an unused pin. Open grid on super high S tubes can pick up signal from anything in the neighborhood)


I am headed back to bed. Gotta get some fresh juices down and some sleep. Monday night is Mono at the Hi-Tone. That is *way* more important than speaker measurements out in the heat. I am a sucker for those shoe-gazing bands.....

Friday, June 4, 2010

iRobot


OK so it has nothing ot do with a mac and it really isn't a robot but one of my boys has a toy that looks sort of like the pic. What it really is..... you guessed it... a pair of MC Step-Ups in a maple case made of Mu-Wood. Obviously since it doesn't have my "Drug through the Hudson" trademark look it was built by someone else. It seemed to work out really well for a first go at it and if they prove to be noise free, a few minor revisions will provide a nice packaging option.



In the above shot you can see the two layers of mumetal sandwiched between the 1/4" maple planks. The inside is copper lined and houses a 1:12 for a 6 ohm cartridge. (Dynavector XV 1S and Lyra Helikon). The "rap test" gives a nice dead sound with no apparent ringing. Ultimately I think the boxes can be made a bit larger and house a stereo pair of transformers but I'm still happy for a first go at it.

dave

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