#Audio transistor

[desertangels70s]

Snoopy Radio made in 1974 by Determined Productions.

[mudwerks]

All Transistor Portable Tape Recorder

[audio-luddite]

Talk about Vinyl

I often mention my system is built around vinyl. But have I really got into my experience with it? What it is like?

Well first lets get technical:

I would like to address the skipping, clicks, pops and noise issue. 95% of the time I do not get any of that. On some of my really old discs yes there is a bit of noise, but I do not mind it. On the rest I keep my LPs clean. By clean I mean I wipe them with special fluid and a discwasher pad usually before every play. Noise is dirt. No dirt no noise. There may be some residual tape noise down 60 dB, but it is overwhelmed by the music.

Actually on my really old records what bugs me is a poor mix or excessive compression.

Lower frequencies are sometimes but not always summed between the stereo tracks. Pick a number and mix the two sides together. At 100 Hz the wavelength is 11 feet (3.35 m). If your speakers are 11 feet apart or less you cannot tell where that sound is coming from. A drum has the higher harmonics and sounds that give you the location information. A single low frequency is unlocatable. So mixing the bass has no serious effect.

The treble of an LP depends on the LP and the way it was recorded and mastered. The equipment can respond to far over normal human hearing ranges. I have at least two Phono cartridges that respond to over 43 kHz. The old quadraphonic systems used that for 4 channel LPs.

Dynamic Range is a real limit, but a high quality LP can have 50, even 60 dB of DR. 60 dB is a factor of a million. That is a lot. CDs have more in 96 dB, streams can have more as well. It is a very rare CD or stream that uses very much of it. Current music is usually very compressed. What that means is most of the DR is not used and the signal is kept loud. Classical and Jazz LPs often have excellent DR. I have a direct to disc album that has DR at the LP limit and it is amazing. I have that nutty KODO CD that uses all the the available CD dynamic range but it actually demonstrates you don't need that much.

Audiophile LPs are usually chosen for good DR as well as the other qualities.

OK so that is out of the way.

When I want to play an Album it is usually because I want to have a quiet listen to music. I mean I want to be quiet, the music may get turned up. It takes an hour for my ARC tube amp to warm up and get happy. I may warm it up with a CD or a stream, but then I pull out an LP.

I may have an old tune in my head. I may want to just have another listen to a symphony or Jazz number. I may want to immerse myself in the full width and depth of audiophile nirvana. What to play? I flip through the musical milk crate and see oh here is something.

I pull out the album. I may be Sting's Soul Cages, or Boz Scaggs "Memphis", or Steely Dan's Aja. I choose. I pull it from the jacket and the slip cover and look at the label for what side is up. Do I want a particular song, or the whole thing front to back? Often I have a particular song in mind, but I will usually play the whole thing. The artist had an intention. Would you read a novel from the middle and skip around?

I put it on the player and cue it to start spinning. Always place the record on and pick it off a not moving platter. I mean, do you want to scratch it? Give the brush a spritz of fluid and wipe the record down. Cue the lead in track, set the volume and go sit in the good spot.

Listen. Somebody is sharing a dream or nightmare, or just a bit of their life. Often there are tiny little details hidden in the music to tease you. Sometimes it is just a whole world around you.

In about 20 minutes you have to get up and flip it. I do not mind. Moving is good for you. Maybe fix a drink, or freshen the one you got. There is a whole other side to go.

More often than not I think of another album while the first plays. I get in the mood for more. This usually goes on for hours. That is what it is for.

Audio Research SP 14 preamp, Russian 6N23Pi tube in the phono section.

ARC Classic 60 amplifier with a full complement of Electro-harmonix tubes.

Phase Linear 8000a II linear tracking turntable with AT 7V cartridge

Whatever album I feel like.

[boltlightning]

hades ii — song of the sirens ♫ come to me, rest your head / warm within ocean's bed / rock and sway your worries down / ebb and flow, fast and sound ♫

[chaptertwo-thepacnw]

elgin transistor radio circa 1964 |2023|

[melonymint753]

Transistor anniversary? Meme repost time

[takmiblog]

差動回路で構成した優等生には出せない味がある

ぺるけさんとこの「トランジスタ式ミニワッターpart2」です 前回、正負両電源の19V版（最終版）を作ったというのに、初期型の単電源仕様のpart2を作るのは本来なら有り得ない事です 逆行も甚だしいこの流れは、変態の愚行と言わざるを得ないことです

but　探求心と好奇心には逆らえない

先に、感想を書きますと この12V単電源仕様のOTLアンプは　とてもいい音がします　僕はこの音の感じ　すきですね 差動回路で構成した優等生には　出せない味がある 回路は簡単だし、FETの選別に悩まなくていいし、省エネ　

(https://agc.ne.jp/?p=4761)

by Advanced Gear Corporation

(http://www.op316.com/tubes/mw/mw-12v-p2.htm)

[frdd2cass]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--mosfets/si2309cds-t1-ge3-vishay-2000777

Audio mosfet, Mosfet applications, mosfet gate, mosfet switch, Transistor mosfet

SI2309CDS Series P-Channel 60 V 0.345 Ohm Power MosFet Surface Mount - SOT-23-3

[doyoulikethis-videogame-song]

Song: The Spine Artist: Darren Korb ft. Ashley Barrett From: Transistor

Listen on Youtube:

[addohaislam2000]

What is Transistor Mosfets, Transistor mosfet, audio mosfet, small signal mosfet

P-Channel 25 V 1.5 Ohm Surface Mount Digital FET - SOT-23-3

[ddryl2rich]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--mosfets/nds331n-onsemi-1014174

Power mosfet, mosfets, mosfet switch, mosfet gate, super junction mosfet

Single N-Channel 20 V 0.5 W 5 nC DMOS Surface Mount Mosfet - SOT-23

[audio-luddite]

Perfect Speakers

What do I know about the perfect speaker, lots actually.

You see I have built them 4 times. First task is perfect as a concept must be defined. Then a plan that embodies the idea is established. Then you build the sucker.

My first attempt was a big electrostatic. Electrostatic speakers are great everyone says so. Fast accurate and dynamic. Compared to "Statics" cone drivers are dull and slow. Ask anyone. As a first try it seems rather ambitious. Mechanically they are actually very simple. You need a couple of sheets of perforated steel, a mylar membrane, and some plastic strips. You build a layer cake of Steel, plastic strips, Mylar, more strips, and a final layer of steel.

Try making a cone loudspeaker driver in the basement without a lot of weird tools.

There are two tricky bits. One is you have to make the Mylar conductive. In my case I spread a layer of graphite I got from drafting pencil sharpeners. (I did drafting ). The other tricky bit is getting impedance matching transformers to make the hundreds of volts needed to drive the stators which is what the steel sheets are called.

For the actual speaker array I made three panels one foot wide four feet tall and mounted them side by side in a wooden frame. The two on each side were canted out a bit. One such array per channel.

I decided that rather that looking for just transformers I would buy a pair of Tube amplifiers. They had transformers that were audio grade already. Oh and then I could attach the stators directly to the primary windings of the amp for a direct coupled drive. If you know what that means you may even be impressed. I had two problems with that. first is that tube amps were going into the trash more often than the used market, (50 years ago) and I had to rejig the feedback in the amp which came off the secondary winding.

The most amazing thing was I got all this done and it worked. It worked really well. It was perfect and my friends were impressed. My future wife was impressed. (that early exposure to my hobby made her tolerant of my later adventures)

It was great, but.....

Even big electrostatics have funny Bass. Phase cancellation and sounds bouncing around the room were a problem. Not as perfect as legend has them. I added a subwoofer driven by a transistor amp (the HK 12 I still have) That helped, but satisfaction was not to be found. When you have doubts about perfection it is serious.

The experience of two moves with big awkward speaker things eventually to a too small apartment made the situation impossible. I disassembled them and put the parts in storage. (I still have most of them)

The idea of perfection changed. Easier to live with and must fit comfortably in a living room. Hmmmm. Next set was a small pair of boxes using a nice 4 inch woofer I found that was almost full range. It reproduced the human voice with uncanny realism. I put a pair in a tuned box with a tweeter and it worked fine. Small apartment problem solved. It had better bass than the "Statics."

Later we moved into a house. Small boxes are small. I like big music.

Hmmm....

How about taking the nice tiny woofers that sounded so good and using 4 per side, and add a 12" woofer underneath. Biamp the sucker yes that's the idea. I had a wood shop build me the boxes. Tall pyramidal obelisks with 6 divers, bi-amped. ( That Citation 12 was sure handy)

It sounded really good. It filled the room with big sound, yet the human voice was scary real and the timbre of woodwinds was to die for. It resembles a lot of high end beasts sold today. I still have them as the front end of my Video surround setup.

All this time my main amps were the same tube amps I bought years before. They were Dynaco Mk3s, 60 Watts per side, and really easy to upgrade and improve. We had little kids and hot high voltage devices on the floor were a bit scary.

I built a transistor amp from a kit of leftover parts when Dynaco shut down. That is the Franken amp. Less scary and pretty resistant to curious fingers of small kids.

We moved a couple more times, eventually to a nice small house. My wife was patient for a while with the obelisks in the living room but the size was almost oppressive. A couch a chair and a BIG stereo. It was a stereotypical setup and a problem even for me. The compromise was to put the stereo away and use the monster speakers in the AV system downstairs to watch videos with spectacular surround sound. No fragile turntable to damage with bigger kids and their friends. Video Tape, CDs and DVDs were the thing. "Why do you keep all those albums you haven't played them for years?"

The kids got bigger and more responsible and trustworthy. I wanted my old stereo back. I wanted to play my albums.

I had a new idea. There was an ad in craiglist for a strange speaker from Denmark I think. It did not look like a conventional speaker. I had heard a set decades ago. Damn, it sold fast, someone else recognized it. But I could build a set like that. Smallish, modest dimensions and designed to go hard against a wall. Take advantage of Bass reinforcement using a wall and the floor. Tune the box with those cool equations and design a cross-over with a computer program. I knew where to buy good components.

I could make a better version of that Scandinavian set.

So some nice birch plywood, some high end drivers, and some actually rather expensive inductors and capacitors were purchased. I had some decent carpentry skills by now and a few power tools. I ended up with some nice boxes with a natural blonde oil finish. They look good and actually they do not look at all like speakers unless you look hard. I call them stealth. Oh and they sound really good. The best yet.

Better than direct coupled large electrostatics. Better that small boxes. Better than big obelisks. Better than all those. The wife likes them. They are perfect.

[mchel2kssn]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--mosfets/irf4905strlpbf-infineon-8173863

Mosfet transistor, power mosfet, mosfet circuits, mosfet electronics

Single P-Channel 55 V 0.02 Ohm 180 nC HEXFET® Power Mosfet - D2PAK

[chaptertwo-thepacnw]

1970 Sony TR-4100 |2023|

[rbrt2awway]

https://www.futureelectronics.com/p/semiconductors--discretes--transistors--mosfets/irf7240trpbf-infineon-7173864

Transistor mosfet, mosfet module, Mosfet power supply, transistor switch

Single P-Channel 40 V 0.015 Ohm 110 nC HEXFET® Power Mosfet - SOIC-8

[takmiblog]

Mini Watt Tourer Part3

Originally designed by Tetsu Kimura (r.i.p.)

　ぺるけさんはこのPart3を完成させた後、Part4でドライバ段を準差動化し、Part5で差動化しているのだが、大きな流れで見るとこのPart3でmini watterとしての基本が固まりつつあるように思える。

　今、静かに本機で音楽を楽しんでいる。数値的には低域においてクロストーク特性が良いとは言えないのだが、『素直な音』『豊かな音』『大人の音』である。シナトラの歌声が心地よい。数値には表れてこない音楽のいきいきとした躍動が感じられる。しばらくはメインアンプとして味わおうと思う。(2023/09/02)