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Where's Tolly (wavebourn) Been?




 
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Author Topic: Where's Tolly (wavebourn) Been?  (Read 5761 times)
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Wavebourn
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« Reply #25 on: July 20, 2020, 12:01:05 AM »

Please read again, I wrote only what I wrote, i.e. 92 db at least, and 95 dB peak is a normal listening level for myself and many other audiophiles that I know. I never said that it is enough, and neither questioned your personal preferences. :-)

Well, people were doing triodes in 1980Th... ;-)

I understand why, and I respect what they were doing.

There are people who do restoration of vintage cars, and if there is the demand, they make copies. It is their business, not mine.

300B triodes were designed when people knew not much about sound reproduction, capacitors and resistors were quite expensive; it was cheaper to wind transformers and chokes.

In order to get linear sound reproduction they designed special tubes, compromising amplification factor for linearity and low output impedance. They were especially crafted tubes to use in as simple as possible amplifiers. The end result of such amplifiers depends very much on particular tubes. In order to get stereo amplifier you have to match many tubes to find one matched pair. To get better sound you have to select better tubes. Why Western Electric 300B tubes are so expensive, because they were made to sound best in simple amplifiers where everything relied on tubes. Such amplifiers can nor drive properly any speakers. They need speakers that have particular mechanical damping.

However, today we know more, resistors and capacitors are cheaper than in 1930'Th, and can design amps that do not require so strict selection of 300B tubes, but what's the point then if their major properties are not used? For modern amps more convenient tubes are available, they are much cheaper, and are in current production.

For example, in my Edelweiss-3 I can use 6L6, 5881, EL34, KT77, KT88, KT120 tubes, adjusting self-bias by a single potentiometer observing bias on digital gauges under tubes. I can select high output impedance for "current drive" of some speakers like pentode amplifiers without feedback do. For other speakers I can select medium output impedance like triode amps (including 300B) have. I can select low output impedance to drive modern hi-fi speakers that want solid state amplifiers. Or even negative output impedance for servo-damping of speakers making frequency response on bass frequencies more even and extended.

Frequency response of my amps is pretty wide, from 6 Hz to 90 KHz, without special output transformers that cost today a fortune.

And gain of both channels stays the same, no matter which tubes you swap. Dynamic distortions are minimal thanks to solid state voltage regulation and other measures I took while designing my amps. No such "bloating" on overload like in typical 300B amps. No audible hum.

I.e. I design my amps in 21'St century, you can compare them to 5-10 times more expensive amps with 300B tubes and see for yourself, which would you prefer for listening, reliability, and easiness of usage, when you don't need to roll awfully expensive tubes to get clean sound that you love.

And once again, my amps are not SET. They use 2 pentode stages with 3 nested feedback loops, to get transfer curves especially crafted, similar to what Western Electric were getting specially crafting tubes.

In short, Western Electric were trading gain of the tube for desired transfer curves using precise internal geometry. I trade gain of pentodes using external components for similar transfer curves, to get better results cheaper. :-)


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Wavebourn
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« Reply #26 on: July 20, 2020, 12:19:34 AM »

Here you can find some demos of my Edelweiss-3 amp prototypes
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WBear2GCR
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« Reply #27 on: July 20, 2020, 12:12:17 PM »

Please read again, I wrote only what I wrote, i.e. 92 db at least, and 95 dB peak is a normal listening level for myself and many other audiophiles that I know. I never said that it is enough, and neither questioned your personal preferences. :-)

I did read it, and said that 6 watts, no matter what the preference is insufficient, I said why. Done with this topic, ok?

Quote
There are people who do restoration of vintage cars, and if there is the demand, they make copies. It is their business, not mine.

300B triodes were designed when people knew not much about sound reproduction, capacitors and resistors were quite expensive; it was cheaper to wind transformers and chokes.

Incorrect. Caps and resistors were not expensive compared to transformers and chokes at that time.
The 300B was designed by Western Electric's Bell Labs.
You can read the literature, it is free and online now. Bell Labs Journal.

They had available larger tubes as well.

Quote
In order to get linear sound reproduction they designed special tubes, compromising amplification factor for linearity and low output impedance. They were especially crafted tubes to use in as simple as possible amplifiers. The end result of such amplifiers depends very much on particular tubes. In order to get stereo amplifier you have to match many tubes to find one matched pair. To get better sound you have to select better tubes. Why Western Electric 300B tubes are so expensive, because they were made to sound best in simple amplifiers where everything relied on tubes. Such amplifiers can nor drive properly any speakers. They need speakers that have particular mechanical damping.

Historically inaccurate.
The 300B was not designed as a tube for audio amplifiers.

Western Electric designed amplifiers used feedback and did not rely upon close matching
of tubes.

Western Electric tubes are expensive TODAY because not that many original examples survived
into the latter part of the 20th century, far fewer were ever made compared to things like the
807 or 6L6. They were more expensive in the 1960s than a similar power RCA or GE tube (for example).
And they produced less power in a typical circuit, at a time when making power was an important
criterion. So, not nearly as popular.

Quote
However, today we know more, resistors and capacitors are cheaper than in 1930'Th, and can design amps that do not require so strict selection of 300B tubes, but what's the point then if their major properties are not used? For modern amps more convenient tubes are available, they are much cheaper, and are in current production.

As you ought to know there are some very nice Ruskie sweep tubes that when their grids and screens are
tied produce lovely, superior to 300B even, curves.

IF curves are your criterion??

Quote
For example, in my Edelweiss-3 I can use 6L6, 5881, EL34, KT77, KT88, KT120 tubes, adjusting self-bias by a single potentiometer observing bias on digital gauges under tubes. I can select high output impedance for "current drive" of some speakers like pentode amplifiers without feedback do. For other speakers I can select medium output impedance like triode amps (including 300B) have. I can select low output impedance to drive modern hi-fi speakers that want solid state amplifiers. Or even negative output impedance for servo-damping of speakers making frequency response on bass frequencies more even and extended.

This is a very nice feature.
Why is it named Edelweiss?
If he is a designer/engineer, I don't think I am familiar with him.
More information is appreciated.
You can PM, or email, since this is clearly not ham radio related at all!

Quote
Frequency response of my amps is pretty wide, from 6 Hz to 90 KHz, without special output transformers that cost today a fortune.

This is a very strong claim.
I'd like to see your square wave at 1kHz for example - using a fast square wave as input...
for example from the calibrator on a 100mHz Tek scope or equivalent.
I scratch my head at the idea that common output iron will reach 90kHz on a good day going
downhill... (again feel free to email - I won't bite!)

<snip>

Quote
And once again, my amps are not SET. They use 2 pentode stages with 3 nested feedback loops, to get transfer curves especially crafted, similar to what Western Electric were getting specially crafting tubes.

In short, Western Electric were trading gain of the tube for desired transfer curves using precise internal geometry. I trade gain of pentodes using external components for similar transfer curves, to get better results cheaper. :-)

Nested feedback loops will lock the thing in... up to a point. And it is a perfectly valid approach to
design.

I'd suggest you look at the harmonic spectrum out a ways to see what you've actually got going.
Love to see a screen shot both at low power (under 1 watt) mid power and within a fraction of
a dB of "the wall"... but again this is not a ham radio topic.

Anatoliy, I don't have a personal love of the 300B. Imho it has a particular flaw. One that can not
be eliminated by any known means. I think there are better tubes in a practical sense.

You may be shocked to know that my amplification typically is solid state of my own design.
And most of that, now relatively anciently produced.
I am retired. Cheesy

Worn out from these endless "debates" on audio. Don't care any longer. Something close to 98% of
all "audiophiles" I think have significant hearing deficits, so they'll never hear what I used to be
able to easily perceive
. So, I can't hear what I used to either - now I know what they all
are hearing now... HA! It's a bad joke. To me anyhow.

Doing ham radio.
Much more fun now.

So what are you doing in HAM RADIO??


attached is an image of my DC coupled 35w/ch SE MOSFET amp from about 1995... for reference.
(thus the heatsinks)


* SEMosfet-B&W.JPG (137.7 KB, 900x708 - viewed 75 times.)
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Wavebourn
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« Reply #28 on: July 20, 2020, 12:47:09 PM »

Well; in 1995 I was still on my computer - related career path, developing TCP/IP and Unix based network for Kamaz corporation, and offering Internet access for the whole town. Fighting against phone companies for channels, while they were trying to convince the management of the corporation that X25 is the way to go, while TCP/IP does not follow standards of OSI/ISO. And it was 1995 AFAIR when first sources of NCSA Mosaic and CERN HTTPD become avilable, and I implemented first Web-based information system for top management of the corporation.
Speaking of audio, It was still my hobby, but I still believed that vacuum tubes are obsolete, and ICs are the only way to go. :-)

Why I am here, on the forum? Because back in 2001 I liked to listen radio, but found that all bands become dirtier and dirties, but being a former physicist and electronics engineer with a diploma, I could not give it up, and gradually come to tube inputs with strong passive preselectors, then bought vintage 1930'Th Meissner radio receiver and restored it. I sold it to the member of this forum, and bought BC-348, then R390A/URR. I even wanted to get my ham license, but did not have a time for that. And then I was bit by a high end bug and started my vacuum tube path. Well, it was not just "starting" actually; being a kid I used to repair tube radios, then TVs. Back then they were common, transistor radios were new and something special. :-) And of course, I was taught by my professors to design using vacuum tubes, but I thought that I will never use them. :-)
I built my first guitar amp back in 1974 when I was a teenager, it was a tube amp, with Gu-50 output tubes. In order to drive them I added a twin 6N6P triode between concertina phase splitter and output tubes. I did not know that "re-invented" Williamson design then.
And there was no better choice back then to find a forum with well informed and enthusiastic people than this one. And the fact that it is still alive is the best proof.

I know that you followed me on DIY Audio forum questioning almost all my sentences, and AFAIR, you were among people who drove me out of the forum that now is called Prodigy, for my heretical questioning of famous vintage designs that they were cloning. But I hope that you would allow me to stay here, even though I do not have a ham radio license. :-)

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WBear2GCR
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« Reply #29 on: July 20, 2020, 04:58:14 PM »

And there was no better choice back then to find a forum with well informed and enthusiastic people than this one. And the fact that it is still alive is the best proof.

I know that you followed me on DIY Audio forum questioning almost all my sentences, and AFAIR, you were among people who drove me out of the forum that now is called Prodigy, for my heretical questioning of famous vintage designs that they were cloning. But I hope that you would allow me to stay here, even though I do not have a ham radio license. :-)

You are most certainly welcome, from me to be here!


As far as "driving you out"? No, I don't think that ever happened.
I do not know what forum is now called "Prodigy"??
The only audio forum I was ever active in, other than (back many decades ago) USENET, was DiyAudio.com.
I ceased to participate there some years ago, as my life simply led in other directions...

I rather think I did not question you on questioning others use of traditional designs.
However, I would question absolutist statements, unless they were on solid ground.

What we may have is something of a native language user vs. learned language user ?
I don't know for sure.
But for example you used to tend make, and did in this thread now did make categorical, and un-tempered,
unmodified absolute statements. And expect them, I guess (?), to just pass unchallenged.

It is one thing to say, for example, "...I find that I am more than satisfied with what i hear
when I use a 6w amplifier on my true 92dB/1w/1m speakers..."  So, I might ignore such
a statement, as it is not one of fact, it is one of belief or preference. Aka, not
"textbook", unambiguously true. (and/or backed up with empirical tests or similar...)

And, of course I would ask, similarly as I have, how that would work when the headroom is
lacking? BUT, when one makes a categorical statement that non-experts who are
reading will likely take as gospel, then IF I happen to have substantive knowledge
to the contrary, it makes sense to post it for their sake!

I would do the same if the topic were ham radio - but we don't find much if any of that, not
that I am aware of here.

Does this make sense at all?
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WBear2GCR
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« Reply #30 on: July 20, 2020, 05:18:19 PM »

Btw, please do get a ham radio license!

With your training and technical background it ought to very very easy.
The test can be more or less memorized, if necessary.

RF and AM phone is just about as much fun as banging one's head against the
audio wall!  Shocked

Enjoy!

                    _-_-bear

Think of all the fun ur missing!!

You end up doing stuff like this:


* 75A-2 BOOTS UP.JPG (401.03 KB, 1480x1110 - viewed 86 times.)

* MOUSED 75A-3.JPG (641.05 KB, 1480x1110 - viewed 90 times.)

* TUBES 1947 1937.JPG (523.94 KB, 1480x1110 - viewed 83 times.)
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Wavebourn
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« Reply #31 on: July 21, 2020, 04:20:45 PM »

Well;

let me repeat, 92 dB sensitivity in a living room is enough for me and many audiophiles that I know, but it is the minimum for 6W/Ch amp. Of course, higher sensitivity is better. And it never clips, do not compare it to other amps! It gracefully saturates, fooling imagination, so instead of distorted it sounds as if "too loud". Playing with regimes of tubes and 3 nested feedback loops I got a transfer curve that resembles non-linearities of our ears. However, the best result I got with 6CB5A tubes, 6550 are not so realistic.

A friend asked how Edelweiss-3 would play with his 90 dB/W/M JBL speakers. I said that it would not be enough for realistic loudness. He brought them and tried nevertheless. The amp could not deliver the loudness to match a real performance. After that we connected his speakers to my Gubernator-71 45W/Channel SE amp, with Edelweiss-3 preamp, and were blown up by an orchestra sounding in my living room, as if in a philharmonic hall. :-)
There are no miracles: want to drive lower efficiency speakers getting high end sound quality, be prepared to spend money on an amp (once) and electricity (always)!

Here is the video on Facebook

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WBear2GCR
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« Reply #32 on: July 21, 2020, 09:09:20 PM »

Anitoliy,

The topic here is AM ham radio...

I'll leave you to talk about the audio issues over on DiyAudio or some other suitable
venue. Facebook? Ok?

If you wish to email me, you can click on the email near my avatar.

So, let's talk ham radio!
What do you think about joining the ranks on-the-air?
And have you ever fired up WebSDRs?

                          _-_-bear
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Wavebourn
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« Reply #33 on: July 21, 2020, 10:26:51 PM »

Well; it is QSO, and the topic is, where's I been. Thank you anyway for your invitation. Cheesy

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Wavebourn
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« Reply #34 on: July 23, 2020, 04:11:02 PM »

Still, the question reminds unanswered. What charges can I face if sell UV-C lamps that protect users from rays using 3.5 GHz 30 mW radar?

People need them, and need ASAP. Who can I contact to get an exception?

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KD6VXI
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« Reply #35 on: July 23, 2020, 09:30:00 PM »

Thank you Shane, can you give me some more information, what kind of units, where to find them?





https://www.google.com/search?q=pir+ultrasonic+motion+detector

Will return many different styles.  Both wall, ceiling and standard Decora style.

From there, pick and choose what would work.

I typically use ceiling mount, low voltage (with 'power pack and low voltage dimming) for work, which is probably useless for you.

A normal Decora style if it could be incorporated in your design maybe?

--Shane
KD6VXI
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Wavebourn
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« Reply #36 on: July 24, 2020, 01:20:39 AM »

Wow! Thank you Shane, I did not know that they are in production!
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