New Heathkit AS101 owner - First post.

[alancohen]

I don't undertand how it can be called a 'design' if it's wired that way.

Did you read this page that I posted earlier?

DIY Speakers

It's wired that way because it achieves the desired result. If you don't agree, you can take it up with Bruce Rozenblit. It's his design. And design is something I'm guessing he knows something about.

[Cal Weldon]

Hi Alan,

I'm not doubting that, I am just confused. Why would you not want to keep the impedance constant? Does the shunting cause an excess heat build-up in the L-pad so you're better off changing the impedance the amp sees?

I am curious.

[Cal Weldon]

Hi Alan,
Why would you not want to keep the impedance constant?

Oh man, time to eat crow. I was so concentrated on the L-Pad, I didn't notice you were using it for a FR driver. While my thoughts hold true for a tweeter, when you use it on a single driver it all makes sense. Sorry for the confusion.

Did you read this page that I posted earlier?

No. (head held in shame)

[alancohen]

Oh man, time to eat crow. I was so concentrated on the L-Pad, I didn't notice you were using it for a FR driver. While my thoughts hold true for a tweeter, when you use it on a single driver it all makes sense. Sorry for the confusion.

No. (head held in shame)

No crow, shame or apology required. It seemed you had a little L-pad obsession going on so I though I'd reiterate. Like I said in my monologue, I'm a couple of months removed from technical knowledge ground zero. I took 2 basic circuits classes at 20 in a local community college and that's was it for the next 30 years. I had designs on getting into the electronics field back then, but life took me in another direction. Whatever it was that clicked for me back then has awakened a bit now. But the desire far exceeds the capability.

[voice of the theater]

Did you read this page that I posted earlier?

DIY Speakers

It's wired that way because it achieves the desired result. If you don't agree, you can take it up with Bruce Rozenblit. It's his design. And design is something I'm guessing he knows something about.

I just checked out his website. Bruce is an interesting guy--I like his philosophy/attitude regarding audio. Cool "top ten" list here (of course, we'd all have a different top ten list personalized to our own tastes but his is interesting to say the least): About Us



Some interesting products here: Products

I used to love some of the old Dynaco kits. Obviously, these kits are a whole different breed/niche market, but they bring back memories nonetheless....

[alancohen]

I just checked out his website. Bruce is an interesting guy--I like his philosophy/attitude regarding audio.

Me too. I was trying to think about how I came upon him. It wasn't that long ago time-wise. Maybe quite a bit mileage-wise so it seems longer. Then I remembered. Here's my story if you care to read:

I was a poor man's audiophile in my early 20s, but like most of us, had champagne taste and a beer pocket. I had the best equipment I could afford and listened to music all the time. All my friends were musicians and quite a few went on to be very successful professionals. I played a little guitar, but mainly I was the sound guy for all the middle school bands and all through high school. I loved turning the knobs and bringing the gig to life.

I don't know when it happened, but I got lazily seduced by digital over the years. It started with CDs and then MP3 files. It seemed so easy. It happened so slowly that I never noticed that I was listening, I mean really listening, less and less. In hind sight I guess I assumed it was life encroaching and leaving less time for music. What I have come to realize in the past few months is that it wasn't life's fault. It was the faulty, anemic digital signal. It no longer required the best gear because nothing would help those compressed, degenerated MP3 files. So I slowly drifted away.

Before my recent rebirth, my audio system was a pair of tiny Advent bookshelf speakers with a KLH sub, basic Onkyo receiver and an iPod for input. Yes, I had fallen that far. I used it mostly for TV and hardly ever listened to music. Why bother, it sounded like crap.

Then, as fate would have it, I decided to get back into guitar. I tend to be fairly frugal and pride myself on researching and learning everything I can before making a decision. I decided that I needed a tube amplifier and after many internet hours I decided an old Fender Tweed Deluxe was for me. But spending $2000 on a boutique 12W amp was not going to happen. I found there are kits available and my journey started here:

First build - Boothill 5E3 - Need some help - Telecaster Guitar Forum

Was it really only August! Seems like years ago.

During the process of getting my amp built and running with the help of the board someone posted a link to this guy's blog:

http://sharksphotos.yolasite.com

All of a sudden I felt very inadequate. Scroll down that page and you'll see what I mean. I never saw anything like that. The wiring job itself was a work of art to me, let alone the aesthetics of the chassis. Just beautiful. I was like a junky that just didn't know it yet.

I involuntarily followed the rabbit down the rabbit hole and found Bruce's website. Now granted, his personal wiring jobs of his own amps aren't nearly as OCD as Mark's, but it was the sound of his amps and their design philosophy that was the inspiration.

So my audio system quest began. First I built a pair of his DIY speakers. I figured nothing else mattered until I at least had decent speakers. Then it was time to build a preamp. His Grounded Grid, as I had come to learn, is a fairly well known and widely modified preamp and from what I've gleaned, can't be bested for triple the $499 kit price. It took me 3 hours to build and I had a very acceptable triode-based preamp.

My next project was his long discontinued 3W cathode follower amp Transcendent Sound Cathode Follower Tube Amp. I bought the instruction manual for $15 and started shopping for parts. I hadn't done anything like the before so sourcing everything was a challenge. Here's my thread for that build.

CFA Build... - Transcendent Sound Message Board

Next I started shopping for a turntable. Thankfully, something prevented me over the years from disposing of my vinyl collection. I found a really clean 1st gen Technics SL1200 for $200 and incorporated it into the system. Even before upgrading the tonearm and cartridge it did not take long to reboot my memory banks and remember how great it was spinning vinyl. I A/B'd an LP with the same music from iTunes and the light came on. That's what was missing!! The vinyl sounded real to me. It sounded...musical. The compressed digital source sounded harsh and stagnant.

That brings us to the present with me awaiting my order for a phono preamp and the Son of Beast 15W push-pull OTL. I haven't heard what an OTL sounds like, but it's supposed to be very transparent and open. That sounds like it's right up my alley. The 3W CFA amp I have now pushes these Heathkits to very loud levels and they have added a dimension I had previously not known. I can't imagine what putting 15W into them will do. While waiting for my next components I'm going through all my records and basking in the memories. With these speakers and this system it's like hearing them again for the first time.

So that's my story. I'm no electronics, acoustic or audio expert by any means nor do I pretend to be, nor do I really have time to be. I still have that champagne taste, but maybe now with imported beer pockets. I can't afford $25K in sound equipment, let alone $250K, but I know what I like and what sounds good to me. I also like building things so this DIY audio gig seems to fit me very well.

Most importantly, I'm learning to just sit and listen again...really listen.

[gearfreak]

That brings us to the present with me awaiting my order for a phono preamp and the Son of Beast 15W push-pull OTL. I haven't heard what an OTL sounds like, but it's supposed to be very transparent and open. That sounds like it's right up my alley.

Looking forward to knowing what you think of the OTL amps, though the 15W version would be more than too much for me. I was looking at the ~1.5W and ~4W single-ended models.

* Noting that the Trancendent design/s (?) spec low output impedance.

Anyone else playing with OTL's, SE/OTL's ?

[alancohen]

Looking forward to knowing what you think of the OTL amps, though the 15W version would be more than too much for me. I was looking at the ~1.5W and ~4W single-ended models.

* Noting that the Trancendent design/s (?) spec low output impedance.

Anyone else playing with OTL's, SE/OTL's ?

Me too! I'm a little concerned. In Bruce's words "The result is an unbelievable clarity and realism that no other configuration can achieve. The music leaps out of the loudspeaker and floats in the room eliminating any “box” like sound. It is silky smooth yet possesses uncanny detail and three dimensional imaging. It has to be heard to be understood. Words alone cannot reveal the OTL tube amp experience."

So far my new Heathkits have done that already. I'm a little scared to think what both combined might image like.

15W is probably overkill for me too. The 3W transformer-coupled cathode follower I'm using is more than enough, but the room they will eventually end up in is 25' x 40' and I might need the extra headroom. Besides, the 15W is actually more affordale due to the most recent redesign change that eliminates the separate high voltage and bias transformers. It actually runs cooler too.

You might want to look into his 300B, 1W monoblocks. Rumour has they are the shizzle.

BTW, my new caps arrived. Yippee!

[voice of the theater]

.....BTW, my new caps arrived. Yippee!

Every vintage Altec I've ever recapped sounded noticeably better after a re-cap and thorough cleaning of the crossover pots/L Pads with deoxit (to varying degrees--some sounded surprisingly better, some had more of a subtle improvement but definitely still noticeable). Drum roll, please!

[alancohen]

Gearfreak: Or, you can buy these!!

W Classic Western Electric Altec 300B Single Ended Stereo Tubes Power Amplifiers | eBay