John Curl's Blowtorch preamplifier part II

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During a power struggle at Harman about 13 years ago, a sneaky and defensive sales guy blamed engineering for not providing him with something to sell in the desktop powered speaker space with MSRPs at 100 bucks and below. We came up with a few ideas but in the end the insistence on large margins made it impossible to compete with manufacturers willing to work with lower ones.

All of these things became negligible after the new CEO dismantled the division, having offered to people the alternative of moving to China, which no one wanted to do.
I was one of those who was offered to go to China for 2 years. I thought about it for a minute then I reminded myself about the air quality over there.

The guy who first came up with the dismantling idea proposed it to the CEO and the idea was so welcomed that the progenitor himself was put on the chopping block list. I can't help but play in my head Gomer Pyle syaing "Well surprise, surprise, surprise" :D Almost made me believe in divine intervention.

It was a bit more than just competing with commodity pricing pressures. It was also a clash of one group who was happy with a continuation of 70's box speaker engineering mindset vs another who were working with curved, molded plastic designs based around the design ideas of a really good artist, concept guy named Kurt Solland. Kurt can hand carve these insanely good foam models and he has a great eye for form and function.
 
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I was one of those who was offered to go to China for 2 years. I thought about it for about a minute then I reminded myself about the air quality over there.

The guy who first came up with the dismantling idea proposed it to the CEO and the idea was so welcomed that the progenitor himself was put on the chopping block list. I can't help but play in my head Gomer Pyle syaing "Well surprise, surprise, surprise" :D Almost made me believe in divine intervention.

Ha ha - yes!


I spent 5.5 in Japan (AQ very good in Tokyo), 3.5 in Taiwan (AQ no where near Japan) and 9 months in Shanghai. Terrible some days. Was glad to get out in the end.
 
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Exactly. Fine if someone subjectively prefers something, as you say, one might be curious as to the reason, but that's it. The problem is when it is claimed to be objectively superior....

And on the general topic, I still have never seen (apart from duff equipment or installs, which I though we would be beyond...) a system with a power noise or hum problem - not since the 70s anyway.

I agree with you and Derfnofred's statement. But, it does not stop it happening unfortunately. We have to take it as it comes I am afraid.


Separately, there are noise issues out there, no doubt about it. I'd say the situation is better than it used to be. I remember every time the refrigerator kicked in, the radio would burp, or if you turned a light on the hi-fi would click. run the vacuum and the radio was unlistenable (AM in those days!)
 
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Brad,
What was the purpose of a compressor in that Duet speaker with a 2" cone driver? A compressor or a limiter?
It allowed more bass at moderate levels, while preventing things from totally falling apart at higher ones. The effect was to reduce overall gain with level, but sooner with low frequencies. This is now usually done in the numeric domain, but at the time it was something that we did a lot, generally by changing the Q of an underdamped highpass at a frequency around the port tuning.
 
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I was one of those who was offered to go to China for 2 years. I thought about it for a minute then I reminded myself about the air quality over there.

The guy who first came up with the dismantling idea proposed it to the CEO and the idea was so welcomed that the progenitor himself was put on the chopping block list. I can't help but play in my head Gomer Pyle syaing "Well surprise, surprise, surprise" :D Almost made me believe in divine intervention.

It was a bit more than just competing with commodity pricing pressures. It was also a clash of one group who was happy with a continuation of 70's box speaker engineering mindset vs another who were working with curved, molded plastic designs based around the design ideas of a really good artist, concept guy named Kurt Solland. Kurt can hand carve these insanely good foam models and he has a great eye for form and function.
Yes Paliwal dismantled the only division in the Consumer Group that was making money. Prior to that, Gina reneged on the contractual agreement that Kurt had with Druckrey, so he said bye-bye. And a recently-departed person long with JBL never stopped calling what Multimedia did as "toy loudspeakers".

The phenomenon of digging one's own grave is a time-honored Harman tradition.
 
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I'd say the situation is better than it used to be. I remember every time the refrigerator kicked in, the radio would burp, or if you turned a light on the hi-fi would click. run the vacuum and the radio was unlistenable (AM in those days!)

Yeah, I remember too... But it's been a long time since an audio system went bump-bumpty-bum-bump as a GSM phone camped near to it... :)
Mind you, I have transmitters that would break through any system you are likely to devise - the solution is to tell me to switch off or move away! :spin:
 
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Yeah, I remember too... But it's been a long time since an audio system went bump-bumpty-bum-bump as a GSM phone camped near to it... :)
Mind you, I have transmitters that would break through any system you are likely to devise - the solution is to tell me to switch off or move away! :spin:

Well most people are on 3 or 4G, but out in the sticks we still get some 217Hz pickup.
 
If you learn what is common-mode and differenetial or normal mode on the ac line, then you will know why there are caps from each H and N to ground and from H-N.

Then you will need to know which mode you have in your home/system and proceed to get rid of it. [I already said which it is]


THx-RNMarsh

No.

You can use them to reduce noise that might be required in certain settings, and the amount of noise added to ground might be "tolerable" but it's unacceptable when your goal is the best playback possible.
 
Yes Paliwal dismantled the only division in the Consumer Group that was making money. Prior to that, Gina reneged on the contractual agreement that Kurt had with Druckrey, so he said bye-bye. And a recently-departed person long with JBL never stopped calling what Multimedia did as "toy loudspeakers".
That recently departed person once remarked on the per unit dollar amount of profit on his designs verses a Multimedia unit. The problem was that the Multimedia unit was shipping on the order of 100k pieces a day. His units were, well, shipping many, many orders of magnitude less.

The phenomenon of digging one's own grave is a time-honored Harman tradition.
:D Like: "hey! I got an idea! We will close the last vestige of proper Northridge, CA. manufacturing worthy of the badge "JBL" and move it to Mexico." The board room screams in delight!
 
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No.

You can use them to reduce noise that might be required in certain settings, and the amount of noise added to ground might be "tolerable" but it's unacceptable when your goal is the best playback possible.

Yes. If you know the type of noise... you might not even need to send any of it to ground.

And where do you place Your ac power isolation transformer(s)?

What does your grounding system look like?

Excuse me. If you need this ----> I was responsible for all the power and grounds on an experimental test accelerator facility built from the ground up... accel power, controls, computers and diagnostics and all their signal and power ground systems. Ditto the Fusion energy program/facility. They dont let you do that if you dont have a track record and know what you are doing.


THx-RNMarsh
 
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It is getting on to 39 years ago (1977) since I started working at HK as a consultant (JBL as well), and this was before Dr. Toole, et al came in and insisted on double-blind tests, etc. We had resident, management level listening guru's who would make the listening decisions. They could be biased on occasion. It surprises me how many on this thread actually have made that journey into HK and JBL. I liked JBL direct radiators at the time, but their horns were out-of-date even in the early 70's, but apparently they improved them in decades after. Electronics was so-so, with many engineers stuck in the past. Good job as far as it went, with me, for the year and 1/2 that I worked with them. They never really used any of my designs, but I later built a 30ips master recorder based on the design modules that I developed for a CD recorder that they decided not to make. Thanks HK, for the experience.
 
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Electronics was so-so, with many engineers stuck in the past. Good job as far as it went, with me, for the year and 1/2 that I worked with them. They never really used any of my designs, but I later built a 30ips master recorder based on the design modules that I developed for a CD recorder that they decided not to make. Thanks HK, for the experience.
One guy who works elsewhere now worked for JBL Pro for a while, and so many products he was involved in were shut down that he became known informally as Vice President of Cancelled Programs.
 
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