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Gareth Magennis May 22nd 12 06:38 PM

Allen and Heath PA CP
 
1 Attachment(s)


John Larkin May 23rd 12 04:42 PM

Allen and Heath PA CP
 
On Tue, 22 May 2012 18:38:48 +0100, "Gareth Magennis"
wrote:



Audio designs are so bizarre. What's with the diode quad in the U1A
feedback path?


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

Jim Thompson[_3_] May 23rd 12 05:26 PM

Allen and Heath PA CP
 
On Wed, 23 May 2012 08:42:40 -0700, John Larkin
wrote:

On Tue, 22 May 2012 18:38:48 +0100, "Gareth Magennis"
wrote:



Audio designs are so bizarre. What's with the diode quad in the U1A
feedback path?


It's like the human appendix, a vestige left over from the past, no
longer useful, but still dangling there. My guess is the "designer"
simply popped in FET's Q16, and Q21, replacing an NPN and a PNP
respectively.

I get a kick out of such crap "designs"... some slug heard that FET's
would be better, so that's what you get... crap with FET's ;-)

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Jasen Betts[_2_] May 24th 12 12:45 PM

Allen and Heath PA CP
 
On 2012-05-23, John Larkin wrote:
On Tue, 22 May 2012 18:38:48 +0100, "Gareth Magennis"
wrote:



Audio designs are so bizarre. What's with the diode quad in the U1A
feedback path?


Looks like it enforces clipping, perhaps because U3 is too slow to
respond immediately to clicks.

I suspect most of the time feedback is only via R7,R72

--
š‚šƒ 100% natural

Jim Thompson[_3_] May 24th 12 05:09 PM

Allen and Heath PA CP
 
On Wed, 23 May 2012 09:26:44 -0700, Jim Thompson
wrote:

On Wed, 23 May 2012 08:42:40 -0700, John Larkin
wrote:

On Tue, 22 May 2012 18:38:48 +0100, "Gareth Magennis"
wrote:



Audio designs are so bizarre. What's with the diode quad in the U1A
feedback path?


It's like the human appendix, a vestige left over from the past, no
longer useful, but still dangling there. My guess is the "designer"
simply popped in FET's Q16, and Q21, replacing an NPN and a PNP
respectively.

I get a kick out of such crap "designs"... some slug heard that FET's
would be better, so that's what you get... crap with FET's ;-)

...Jim Thompson


Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Michael A. Terrell May 24th 12 07:32 PM

Allen and Heath PA CP
 

Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)



Isn't 'Allen and Heath' the company that EEyore used to brag about?


--
You can't have a sense of humor, if you have no sense.

Jim Thompson[_3_] May 24th 12 07:56 PM

Allen and Heath PA CP
 
On Thu, 24 May 2012 14:32:55 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)



Isn't 'Allen and Heath' the company that EEyore used to brag about?


I have no idea... I don't recognize that name at all.

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Michael A. Terrell June 2nd 12 12:34 AM

Allen and Heath PA CP
 

Jim Thompson wrote:

On Thu, 24 May 2012 14:32:55 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)



Isn't 'Allen and Heath' the company that EEyore used to brag about?


I have no idea... I don't recognize that name at all.



Annoying British guy named Graham that hated America. In one post he
stated that the entire US shout be nuked into a sheet of glass. He was
also whining that young girls he thought were flirting with him ended up
treated him like their grandfather.


--
You can't have a sense of humor, if you have no sense.

Jim Thompson[_3_] June 2nd 12 06:07 PM

Allen and Heath PA CP
 
On Fri, 01 Jun 2012 19:34:10 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

On Thu, 24 May 2012 14:32:55 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)


Isn't 'Allen and Heath' the company that EEyore used to brag about?


I have no idea... I don't recognize that name at all.



Annoying British guy named Graham that hated America. In one post he
stated that the entire US shout be nuked into a sheet of glass. He was
also whining that young girls he thought were flirting with him ended up
treated him like their grandfather.


I've had that problem since my early '40's. Female employees
approaching me to discuss their personal problems with a "father
figure" :-(

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Phil Hobbs June 2nd 12 06:44 PM

Allen and Heath PA CP
 
Jim Thompson wrote:

On Fri, 01 Jun 2012 19:34:10 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

On Thu, 24 May 2012 14:32:55 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)


Isn't 'Allen and Heath' the company that EEyore used to brag about?

I have no idea... I don't recognize that name at all.



Annoying British guy named Graham that hated America. In one post he
stated that the entire US shout be nuked into a sheet of glass. He was
also whining that young girls he thought were flirting with him ended up
treated him like their grandfather.


I've had that problem since my early '40's. Female employees
approaching me to discuss their personal problems with a "father
figure" :-(


Remember the Official Rules.

http://tinyurl.com/cbbgns9

Related to these is the Prime Directive: "Never eat anything bigger than
your head."

Cheers

Phil Hobbs

Jim Thompson[_3_] June 2nd 12 07:23 PM

Allen and Heath PA CP
 
On Sat, 02 Jun 2012 13:44:24 -0400, Phil Hobbs
wrote:

Jim Thompson wrote:

On Fri, 01 Jun 2012 19:34:10 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

On Thu, 24 May 2012 14:32:55 -0400, "Michael A. Terrell"
wrote:


Jim Thompson wrote:

Oooops! Wrong "quad". My comments apply to D27 and "south".

Maybe D15, et al, are to produce some of that "toooob" sound ?:-)


Isn't 'Allen and Heath' the company that EEyore used to brag about?

I have no idea... I don't recognize that name at all.


Annoying British guy named Graham that hated America. In one post he
stated that the entire US shout be nuked into a sheet of glass. He was
also whining that young girls he thought were flirting with him ended up
treated him like their grandfather.


I've had that problem since my early '40's. Female employees
approaching me to discuss their personal problems with a "father
figure" :-(


Remember the Official Rules.

http://tinyurl.com/cbbgns9

Related to these is the Prime Directive: "Never eat anything bigger than
your head."

Cheers

Phil Hobbs


Yep. I once got stuck in a week-long HR (GenRad) seminar on sexual
harassment. When I allowed as how I wished some babe would sexually
harass me, the HR woman was _not_ amused ;-)

Those GenRad HR meetings were nasty... they wouldn't even let us leave
the building for lunch... I guess for fear we'd "sedate" ourselves.

I once drew their serious ire... I hosted a pre-Thanksgiving luncheon
for my whole department... my wife brought turkey and all the fixin's,
and wine and beer iced in wash tubs... all set up in the lab.

HR went ballistic and threatening. I responded, "So fire me... I'll
just go down the street".

Bob Fulks (OmniComp President and VP of GenRad-Phoenix Operations)
interceded and they STFU.

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Michael A. Terrell June 4th 12 11:39 PM

Allen and Heath PA CP
 

Jim Thompson wrote:

I've had that problem since my early '40's. Female employees
approaching me to discuss their personal problems with a "father
figure" :-(



Such is life. :)


--
You can't have a sense of humor, if you have no sense.

Michael A. Terrell June 4th 12 11:40 PM

Allen and Heath PA CP
 

Phil Hobbs wrote:

Related to these is the Prime Directive: "Never eat anything bigger than
your head."



No one ever told my dog. He once ate a bone that was bigger than his
body, even though it took him a month. :)


--
You can't have a sense of humor, if you have no sense.

Michael A. Terrell June 7th 12 08:15 AM

Allen and Heath PA CP
 

Fred Abse wrote:

On Mon, 04 Jun 2012 18:40:34 -0400, Michael A. Terrell wrote:

No one ever told my dog. He once ate a bone that was bigger than his
body, even though it took him a month. :)


Are the Smithsonian still looking for it?

;-)



No. The 'Statute of Limitation' ran out sometime in the '80s. :)


--
You can't have a sense of humor, if you have no sense.


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