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WawaWHUT? This is one confusing preamp!

#104
Forgive me for being picky, but the bias scheme shown in the patent application is NOT grid leak bias, in fact it's no different than the vast majority of conventional common cathode voltage amplifiers used in just about every commercial tube preamp in the industry. Tom, do you have information that is different from the published patent info, or is the patent info not accurate? Something isn't right here, somebody doesn't seem to understand what grid leak bias is. With a grid resistor to ground of 1M, it's still conventional from every definition that I know.

How does the output of the preamp drive a conventional power amp? A 500k pot on the output feeding a real world power amp is going to have a very, very odd taper curve in practice, and will have tremendous transfer losses except at 100% (full up). Did you ever run a frequency response plot versus output control position with say a standard 10k load? I think this would be a fascinating and revealing excercise myself... something I would expect in a review. where the results should be pretty interesting from looking at the patent diagram. (hint... HF boost compensation will not track)
 
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#105
agedhorse said:
Forgive me for being picky, but the bias scheme shown in the patent application is NOT grid leak bias, in fact it's no different than the vast majority of conventional common cathode voltage amplifiers used in just about every commercial tube preamp in the industry. Tom, do you have information that is different from the published patent info, or is the patent info not accurate? Something isn't right here, somebody doesn't seem to understand what grid leak bias is. With a grid resistor to ground of 1M, it's still conventional from every definition that I know.

How does the output of the preamp drive a conventional power amp? A 500k pot on the output feeding a real world power amp is going to have a very, very odd taper curve in practice, and will have tremendous transfer losses except at 100% (full up). Did you ever run a frequency response plot versus output control position with say a standard 10k load? I think this would be a fascinating and revealing excercise myself... something I would expect in a review. where the results should be pretty interesting from looking at the patent diagram. (hint... HF boost compensation will not track)
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I agree.
 
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#106
Munjibunga said:
Hey, after watching this, I've decided I just can't live without one of these things.

Click to expand...

This video and the Earcandy one from a few weeks ago make an amazing double feature. I hope these two companies merge someday and their respective founders splice together their DNA together to create a child that makes dubious bass products and then does hilariawful Youtube reviews on them.
 
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#107
agedhorse said:
Any of you engineering guys take a look at the patent, and the published circuits in the patent and the specific claims in the patent?

What is claimed in the marketing is significantly different than what is claimed and shown in the patent paperwork.

If you (engineering types) redraw the schematic so that B+ enters from the top in the usual manner, you will see why the marketing claims make no sense compared specifically to the patent. In fact, it looks like the patent covers only the use of paper-oil caps and "orange drop" film caps which is puzzling to me. I wonder if there is something else going on that we are missing?
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Sometimes the claims of a patent get narrowed significantly during the examination process, to steer clear of prior art that is discovered by the examiner. Yet the claims can't be changed arbitrarily -- they still have to be described in the body of the patent. But if the inventor still feels that the patent does it job to protect what they consider to be vital, then they will modify the claims and forge ahead. This can lead to some pretty bizarre looking claims in patents.
 
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#113
agedhorse said:
Forgive me for being picky, but the bias scheme shown in the patent application is NOT grid leak bias, in fact it's no different than the vast majority of conventional common cathode voltage amplifiers used in just about every commercial tube preamp in the industry. Tom, do you have information that is different from the published patent info, or is the patent info not accurate? Something isn't right here, somebody doesn't seem to understand what grid leak bias is. With a grid resistor to ground of 1M, it's still conventional from every definition that I know.

How does the output of the preamp drive a conventional power amp? A 500k pot on the output feeding a real world power amp is going to have a very, very odd taper curve in practice, and will have tremendous transfer losses except at 100% (full up). Did you ever run a frequency response plot versus output control position with say a standard 10k load? I think this would be a fascinating and revealing excercise myself... something I would expect in a review. where the results should be pretty interesting from looking at the patent diagram. (hint... HF boost compensation will not track)
Click to expand...
Do you possibly have something against 1960s Bogen PA amplifiers?
 

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