Film-Tech Forum ARCHIVE: Transistor Is 50 Today

This is topic Transistor Is 50 Today in forum Film-Yak at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=8;t=002135

Posted by Mark Gulbrandsen (Member # 72) on 06-10-2003, 09:10 PM:

I heard today that the transistor is 50 years old. I didn't hear anything about it in the news, so thought I'd see if any of you heard anything. The guy told me that the first germanium transistors costed in excess of 50 bucks each!
Mark

Posted by Daryl C. W. O'Shea (Member # 1303) on 06-10-2003, 09:14 PM:

TI.com: The World's First Transistor Radio

TI.com: TI Produces First Commercial Silicon Transistor

Posted by Joe Redifer (Member # 3) on 06-10-2003, 10:32 PM:

Yay transistor! What will they think up next? Relays? Resistors? So much potential!

Posted by Ken Layton (Member # 133) on 06-10-2003, 11:13 PM:

Transistor=BAD [evil]

Tube=GOOD

Posted by Mark Gulbrandsen (Member # 72) on 06-10-2003, 11:15 PM:

Tube = Ancient [Roll Eyes]

MOSFET Transistor = Modern [Cool]

Posted by Randy Stankey (Member # 64) on 06-10-2003, 11:43 PM:

If you take two diodes and connect them "head to head" or "tail to tail" and put electricity through two of the inputs, one of the diodes will start to work backwards! It's such a fiendishly clever concept! Who would have thought that up?

Okay, it's not all like that. The discovery was a semi-accident. And, No, the transistor isn't simply two diodes crammed together but it's functionally true.

It took me years to fully understand how a transistor works until somebody told me to look at it that way. Vacuum tubes were easy. Electrons are either blocked or passed based on the voltage on the screen. The idea that you actually WANT a diode to "avalanche" and make that property work for you was just beyond me.

I didn't put 2 and 2 together until I was asked, "Do you know what a Zener diode does?" I said, "Yes, it blocks electrons unless they are at or above the Zener voltage." His reply was, "What if you could vary the Zener voltage by varying the voltage on a third input?... TRANS-resISTOR... TRANSISTOR... Get it?"
"Oooh! I GET it! Cool!!"

Okay, that's a REALLY basic description but I wonder if Bardeen and Shockley said, "Oooh! I GET it! Cool!!"

Posted by Nicholas Roznovsky (Member # 861) on 06-11-2003, 12:58 AM:

I guess its time for me to finally toss out all of those vacuum tubes I've been saving in case they made a comeback...

Posted by Michael Schaffer (Member # 1204) on 06-11-2003, 01:35 AM:

No! Sell them to Ken for a ton of money.

Posted by Bruce McGee (Member # 131) on 06-11-2003, 08:36 AM:

Hey Guys!! Dont give all your tubes to Ken! Bruce needs tubes, too!!

One major problem with transistors on this half-century mark:

Overdrive.

Overload a tube, and you will get an overload sound. Keep it up, and the tube can die.

Overload a transistor, and Phfft! Can you say meltdown?

I'll take a tube power amp over a transistor power amp anyday! Now, a pre-amp is a different use. Small amounts of power, and very little to drive. I've never blown up a pre-amp.

GRIPE: Recently checked out a 1980's transistor amp, and found that the output transistors were shorted, and the things are obsolete and no longer available from any of my 6 suppliers. Chucked the amp. Lets not even talk about those STK amplifier modules that everybody uses these days. Junk Junk Junk and buy a new one!!!---rant off. Feels much better. [Smile]

Posted by Mark Gulbrandsen (Member # 72) on 06-11-2003, 09:08 AM:

Bruce,
I agree partially. I enjoy restoring old tube equipment alot, but solid state amplifiers have definately surpassed tube amplifiers by a large margin in the sound department. It is possible to have a tube amplifier with the characteristics of the mids and highs of a tube amplifier, and the low end of a solid state quite easily....in fact you can even build your own if ya want to. This is something tubophiles have been wanting for many years. I've had alot of tube amps over the years, Atmosphere OTL, BAT, VTL, Western Electric, McIntosh, etc, and have never been really happy with any of them when hooked to a really good pair of speakers. There are limitations either caused by the coupling capacitors, or the output transformers, or other issues, however, power is not an issue with tubes at all....200 watt tube amps are quite common. The only problem is that the very best tube amplifiers do have limited power output and efficient speakers are required to reproduce realistic levels......efficient speakers can be very good but for the most part, medium and low efficiency speakers generally have sound advanyages that efficient speakers don't.

So far the best amplifiers I've owned is a pair of Pass Labs solid state clones that I built last year. There isn't a tube amp on the planet that even comes close to their performance. I've often felt that they are actually better at conveying the real music than can a tube amp. These amps are class A, single ended, all MOSFET, and have only three transistors in the signal path. There are no coupling caps in the circuit unless you use it in balanced mode, and then there is only one. Mine produce 115 watts at clipping into 8 ohms and around 165 watts into 4 ohms. Talk about having your cake and eating it too....this is it and building your own allows you to go way beyond the original design if you want to......for instance mine have power transformers that are 30% larger, also triple the heatsinking of the original factory built units and I have the bias maxed out. A tube amp capable of this much single ended power would be as large as a semi and be perhaps 15 to 25% efficient! These are 50% effiicient and are still class A. Perhaps the only better ampliflers out there are Nelson Pass's later designs that some are now starting to build.
Check it all out on these links and enjoy!
Mark @ CLACO

www.diyaudio.com

www.passdiy.com

www.passlabs.com

http://www.diyaudio.com/forums/showthread.php?s=11cc1c2ceb08e2f81ea419de2695b513&threadid=9159

Posted by Fred Georges (Member # 505) on 06-11-2003, 11:19 AM:

Being a "Horny". I'm used to super efficient loudspeakers being driven by flea powered single-ended (300B output tube) Tube amps. I've owned just about everthing (Built the original Pass single ender out of AA years ago) And for my money still find a great tube amp preferable to solid state. Notice I didn't say "better" because when it comes to high end audio it becomes "preferance". Efficiency IMHO has no bearing on loudspeaker quality. There are good & bad examples of both types [thumbsup]

Posted by Mark Gulbrandsen (Member # 72) on 06-12-2003, 01:56 AM:

Fred,
The old stuff out of AA is nothing compared to what he is doing today. While all the Pass Labs stuff except for the AA stuff is covered by quite a number of patents, as was the older Threshold stuff, he allows, and supports anyone that wants to build any of his patented circuits as long as it is not for commercial venture....
If you want to compare your tiny power tubes to something solid state and comparable....(Apples to Apples) build one of his Aleph 30's...I'd be surprised if you'd ever mess with tubes again unless its for sheer nostalgia. Its also quite inexpensive to construct. I agree that there are good and bad in both worlds of speakers, but I've yet to hear anything with the transparency of the Dynaudio tweeters come out of a horn...even the absurdly expensive horns at the hi-fi shows don't some close, for that matter electrostats don't either.....
Mark

Posted by Fred Georges (Member # 505) on 06-12-2003, 09:50 AM:

I'm in my mid-fortys and in my younger days I mixed Rock-N-Roll shows. "Tweeter"! What the Hell are those?? -LoL . I found the original Pass Aleph a bit too "soft" in the Bass for my taste..Speaker dependent of course..But, My Marantz 9's (Tubes & tweeked) were more solid on my system. I multi amp so I get to chose my "flavors" in the various ranges. These days it's Class A solid state on the woof..Tubes everywhere else. [Big Grin]

My super Tweeters (above 10K) are "Ionovacs" a massless Plasma Horn loaded speaker that looks like a bug zapper when you look down the throat. I don't buy or build any more. I work the room acoustics and that gives me the ultimate bang for no bucks. [Wink]

Posted by Jim Spohn (Member # 1547) on 06-12-2003, 03:20 PM:

One time I was working behind the picture screen after hours and listening to a disk. I noticed that the cones of all the woofers (eight 15" speakers)were moving in and out with about a 1" excursion at the rate of about .5Hz. "OH SH*T!!" I thought, to myself, the output transistors are about to short and apply power-supply potiential to the speakers!! I made a mad dash to the booth to kill the sound system before the speakers started spitting out confetti and smoke. Once in the booth I noticed that the disk I was playing(a phonograph disk)was slightly warped and making the tone arm go up and down at the rate of about .5Hz!! Then it dawned on me...Man O Man talk about direct coupled amplifiers!!

From that day on I was sold on solid state amps for auditorium work......Jim

Posted by Steve Kraus (Member # 476) on 06-16-2003, 01:26 AM:

Mark said:
I've had alot of tube amps over the years...and have never been really happy with any of them when hooked to a really good pair of speakers.

Ha! You coulda fooled me the way you gushed over the sound quality from several successive sets of tube amplifiers! If all that praise is your reaction when you're "never really happy with" something I don't think I'd want to be in the same room when you really are! [Big Grin]