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Bruce Rozenblit

Posted on March 3, 2010 at 09:50:59
I know his name is an anathema for some on this forum, but evidently he's having major health problems.

I haven't received his newsletter in some time--anyone know what's going on?


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RE: Bruce Rozenblit, posted on March 3, 2010 at 11:37:14

Posts: 8937
Location: Bethesda, Maryland
Joined: December 11, 2000
He has done a lot to advance the OTL cause, and I know of no one who thinks of him as an "anathema". I am sorry to learn of his illness. His little book(let) on Vacuum Tube Amplifiers was the first thing I read when I decided I wanted to know more about this subject. Without it, I never would have been able to understand Morgan Jones' book, Glass Audio articles, TubeDIY, etc.


RE: Bruce Rozenblit, posted on March 3, 2010 at 13:07:35

Posts: 3309
Location: Minnesota
Joined: April 24, 2002
April 1, 2002
IMO Bruce has done a lot to legitimize the OTL concept. Its not been an easy road for anyone in the field! I hope he is feeling better soon!


RE: Bruce Rozenblit, posted on March 4, 2010 at 03:23:31

Posts: 48
Location: BXL
Joined: December 16, 2003
hi chris,
FYI, "bruce" is on the better hand now ....
best regards fron brussels,
allez, salukes (otl lover )


RE: Bruce Rozenblit, posted on March 4, 2010 at 06:33:09

Posts: 8937
Location: Bethesda, Maryland
Joined: December 11, 2000
Can you clarify the meaning of your post? The phrase you used could be interpreted in either of two very different ways, at least here in the US.


RE: Bruce Rozenblit, posted on March 5, 2010 at 09:07:15

Posts: 48
Location: BXL
Joined: December 16, 2003
From bruce's letter I deduced that he is feeling better and better.

I think that the best way of getting rid of this very unpleasant situation is to bear patiently with the remaining symptoms and allow nature to complete the healing process.

I appreciate his concern about other people's healths and welfare.
I admire his technical knowledge about amps & OTL.

His courage is remarkable.

To stick the label "anathema" on him never cross my mind . Shame on those who do .

Best regards from Brussels


RE: Bruce Rozenblit, posted on March 5, 2010 at 09:46:58
Karel -

Glad to hear that Bruce is doing better--but I'm still curious to know what the ailment was.

I certainly don't consider him an anathema--far from it. I was merely trying to "flameproof" myself against any people on the OTL Forum who might think that.


RE: Bruce Rozenblit, posted on March 5, 2010 at 12:14:16

Posts: 8937
Location: Bethesda, Maryland
Joined: December 11, 2000
For my part, I do not recall anyone ever declaiming against Bruce Rozenblitt for any personal reason. In fact, most people who have posted here are big fans of his gear. Glad to hear that the outlook is good.


RE: Bruce Rozenblit, posted on March 5, 2010 at 12:19:30
Not for personal reasons--I just remember somebody being critical of his designs.


RE: Bruce Rozenblit, posted on March 5, 2010 at 14:06:47
Dr. Philosophy

Posts: 600
Joined: June 4, 2002
Chris, you can just email him. But also I can email you his newsletter which will tell you about his illness, except that I can't find your address; do you have mine?


RE: Bruce Rozenblit, posted on March 7, 2010 at 05:48:00

From the newletter, he had bad drug interaction for another issue. He is off the drug, but it takes a while to out of his system


isn't he, posted on March 8, 2010 at 14:14:57

Posts: 3140
Location: San Diego County, California
Joined: October 25, 2000
The designer of the Paragon 12 and 12A preamps?

Proudly serving content-free posts since 1984.


No--Grounded Grid preamp (nt), posted on March 8, 2010 at 16:19:07


RE: Bruce Rozenblit, posted on April 13, 2010 at 07:41:22

Posts: 13
Location: No. IL.
Joined: November 22, 2009
From his latest newsletter:
Let us all hope and wish him a full recovery.

Hi Everyone!

I'm much, much better now. I feel like a normal person again. I would like to thank all of the hundreds of people that emailed me wishing me well. It really helps to know that people care. I especially want to thank the three physicians that wrote and essentially validated my analysis. That helped give me the confidence I needed to tough it out and maintain my detox strategy.

I still have some noise in my head but the levels have dropped to where they are not dominating my mind and causing me any undue suffering. Continuing from where we left off, here is how the story has progressed. (For new subscribers, I'm recovering from a bad drug reaction to Avodart that caused terrible noises in my head and sent me into a deep depression).

I had been using white noise generators and fans to mask the noise and provide relief from the torment. This was absolutely necessary. During the first week of March, I made a huge discovery. I was in the vicinity of the air return intake of my furnace blower and I noticed an additional whistling noise in my head. So I stayed put and waited for the blower to shut off. About second after the blower shut off, the noise went away. I then went to my white noise generator and repeatedly turned it on and off. Each time the whistling noise would appear about second after the white noise was turned on and disappear about second after it was turned off. This was a major turning point. I have always maintained that my head noises were generated by over stimulated neurons firing when they weren't supposed to. This confirmed it. The reason I had not noticed this characteristic before was because the neurons were so over stimulated from the Avodart, that they were firing all the time. By mid March, the level of chemical irritation had dropped to the point that the neurons were settling down but still unstable. With additional acoustic stimulation, they resumed firing inappropriately thereby generating these spurious noises in sympathy from external sources.

Realizing this, I turned off all sources of white noise and any fans. These external noises were actually irritating the affected neurons and generating more head noise. Instead of using white noise as a therapy, the best therapy is silence.

I had not had a good night's sleep since Dec. Falling asleep was torture and it often would take two hours of fighting through the head noise to get to sleep. The sleep I did get was very light and would often wake up from the squealing in my head or the external noise sources. That night I decided to try sleeping in a dead quiet room. It worked. In about 20 minutes, the squealing in my head greatly subsided and I was able to get to sleep, really sleep. After sleeping like a normal person for about one week, my depression started to lift. It's gone now. I haven't felt this good since last summer. My energy buzz is beginning to return. There is no way to unscramble screwed up brain chemistry without lots of good solid sleep. It just won't happen.

In the month that has passed since my discovery, the furnace blower does not cause any additional head noise anymore. Fans create a tiny bit of head noise. I have to look for it where previously, these noises were loud enough to find me. This is a big improvement and demonstrates the affected neurons are calming down. A water faucet or shower generates much more pronounced whistling noises because they impart a great deal of high frequency energy. The noises I hear now are mostly a constant high frequency ringing at a low level. When I go outside, it sounds like a hollow whistle in the distance. Last Feb., when things were at their worst, I couldn't hear my refrigerator from more than about 6 feet away. Now I can hear it all over the first floor of the house. The intense hissing, squealing and screeching are all gone. Back then, I had a pronounced squealing that constantly oscillated in frequency and amplitude overlaid on top a foundation of loud hissing 24 hours a day.

My hearing is acting just like a marginally stable amplifier circuit. When a marginally stable amplifier is first turned on, it is stable. Inject a signal and a low level oscillation will develop. Remove the signal and the oscillation will stop. Inject a large amplitude signal and the circuit will develop wild oscillations that will not stop until the circuit is powered down and restarted. This is just how my hearing is functioning.

When I wake up in the morning, my ears are usually almost completely quiet. After I'm awake for about an hour, a generalized ringing starts. Turn on a water faucet and the whistling noise arises in sympathy. Overload the system by subjecting myself to loud noises like in a typical sports bar, and all manner of noises will appear which will require about an hour to decay away. Go to sleep and the system resets and repeats.

This sounds like a problem, but it is a big improvement. There are now periods of little to no noise where one month ago, the noises were on 24 hours a day. Now, if I wake up in the middle of the night, I am met with silence instead of screeching. If I want to stay in bed an extra hour, I can instead of being driven out by head noise.

The Avodart is now down to 25%, which is probably still bioactive. It so strongly affected me within the first 2 hours of the first pill, I may require the concentration to get much closer to zero before it ceases to be bioactive in my body. That could take as long as Aug. 1. Even at that time, my neurons may need additional time to heal. As I understand it, irritated nerves can take months to heal. Since I'm no longer suffering, I can easily ride it out. The problem is becoming a non-issue. I don't think the doctors I talked to had any appreciation of the intensity of the noise in my head. The levels I am experiencing now are probably more akin to traditional tinnitus.

I find it hard to believe that I am the only person in the world that has experienced these types of problems. One newsletter subscriber reports that he has seen this before. He is a director of a nursing home. No one listens to him either. He has seen elderly men on BPH drugs start hearing noises that aren't there or feeling tactile sensations that aren't there. Then they fall into a deep depression. This is what happened to me. The pill pushers then intervene and dope these old timers up on more drugs and they spend their last days in mental oblivion until they are shipped off to the funeral home. Those elderly men are helpless and could not fight back against the pill culture like I could.

I've been pounding on doctors that don't listen but I will say that the system is primarily at fault. Any professional consulting service like engineering, law, accounting, editing, you name it, is billed by the hour. Big jobs take many hours. Medicine is not. It's by the office-visit no matter what the problem is.

I am a professional problem solver with three decades of experience. Problem solving requires more than just raw intellect. It's a learned skill that requires wisdom, patience, being able to separate the emotional response from the logical, and recognizing "tunnel vision" where the obvious is ignored. When designing, I commonly solve integrated, multi-level problems, which can take hours. The human body is tens of thousand of times more complicated than an amplifier circuit. How in the world is a physician supposed to solve a deeply entrenched and hidden problem like I have in five minutes? Can't be done. Not possible. Doctors are human beings and do not possess a Google size database that can be accessed as fast as a mainframe computer. I was suffering so much that I would have gladly written a check for $1000 to buy three or four hours of research time to solve the problem. Cash deal, no paper work, no insurance intervention. This option was not available. Instead, it's what drug can the physician prescribe during a five minute office visit to make this guy go away to push another body through the office. That really stinks and no one would hire any other kind of professional consultant who treated their customers that way. I wouldn't hesitate to spend $1000 on my truck, why not for my health?

I'm OK now. The nightmare is over. I have every confidence that my hearing will continue to improve over the coming months. Many thanks to all my customers for their concern and patience during this trying time. I'm back.


Bruce Rozenblit
Transcendent Sound, Inc.


RE: Bruce Rozenblit, posted on April 15, 2010 at 01:17:11

Posts: 472
Location: near Belgrade / Serbia / Europa
Joined: February 5, 2010
Welkome back BRUCE.Wish You full Health Recovery and good Luck.

"Art which does not have the appearance of art is true art."
- Old Roman saying -


I believe you're thinking of Bruce Moore (nt), posted on April 15, 2010 at 10:06:41



RE: Bruce Rozenblit, posted on June 27, 2010 at 20:43:58

Posts: 6632
Location: Kentucky
Joined: June 30, 2005
When I asked Jim McShane what book I should buy to learn how to build tube amps......................Jim recommended Bruce's books.

So do I.

The Mind has No Firewall~ U.S. Army War College.


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