Close call with my Dodd Preamp

[S Clark]

I had to move my systems around in the past couple of weeks, and didn't realize I had disconnected  the battery charger to my first generation Dodd battery preamp.  So as I was listening to a K&K amp, the pre kept dying after about 40 minutes.  I knew the  batteries were old, so I assumed they had  expired and ordered new ones- not realizing it was  unplugged until I moved it as replacement batteries came in. 
The old batteries were so swollen, I had to cut the frame to get them out.  They had been in for 5+years.  I know some of you guys had that model, and if you still have one, check those batteries.  They may be still playing, but on the verge of popping and making one helluva mess.   

[Nick B]

That's a bit unexpected. Reminds me of some of the YouTube videos seeing phone and computer batteries swollen as well. Any idea if the Dodd batteries are of the lithium type and if certain types of batteries tend to do this more readily than others?

[P.I.]

That's a bit unexpected. Reminds me of some of the YouTube videos seeing phone and computer batteries swollen as well. Any idea if the Dodd batteries are of the lithium type and if certain types of batteries tend to do this more readily than others?

Dodd batteries were all sealed lead acid AGM types.  Mostly PowerSonic brand.

[S Clark]

Yes, they are 5 AH SLA batteries.  The swollen ones were Powersonic, the  replacements are Mighty Max.  I usually get about three years out  of a  set, so  they were  in  service much longer than normal. 
 

[Nick B]

I've heard of lead acid batteries, but have never owned any battery powered gear. Doubt I would go that direction in the future. It's nice that Gary's legacy continues a bit through his products.

[S Clark]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

[Nick B]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

I am not surprised. He had a great reputation as to his products. I understand some areas of his products are sealed/encapsulated so the particulars of his design will remain unknown.

[P.I.]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

I am not surprised. He had a great reputation as to his products. I understand some areas of his products are sealed/encapsulated so the particulars of his design will remain unknown.

Intellectual property rules.  He did things no one else ever considered.  Gary was brilliant, a great friend and gone way too soon.

[Nick B]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

I am not surprised. He had a great reputation as to his products. I understand some areas of his products are sealed/encapsulated so the particulars of his design will remain unknown.

Intellectual property rules.  He did things no one else ever considered.  Gary was brilliant, a great friend and gone way too soon.

Dave,

I get the intellectual property aspect, but I also think it's a shame that products that were so well designed and sounded so good cannot be replicated. How nice it would've been if Gary had made an arrangement with someone else to produce it and maybe get some income for his family or at least allow the product to be named as a Gary Dodd design.

[toobluvr]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

Owned those amps.   Regret selling them.  Sounded killer on my Meadowlark Heron "i" speakers!

Back in the day, an absolute steal.  Memory fades, but IIRC, I paid in the 1500 to 2000 range brand new when Gary first offered them.

[P.I.]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

I absolutely agree about passing his ideas on.  I'm trying to suss out the conversion of my preamp from the twin 6922 amp to the single 6H30 version.  I never got sound to the project and have somehow lost the sparse instructions he gave me right before he passed... 🧐
I am not surprised. He had a great reputation as to his products. I understand some areas of his products are sealed/encapsulated so the particulars of his design will remain unknown.

Intellectual property rules.  He did things no one else ever considered.  Gary was brilliant, a great friend and gone way too soon.

Dave,

I get the intellectual property aspect, but I also think it's a shame that products that were so well designed and sounded so good cannot be replicated. How nice it would've been if Gary had made an arrangement with someone else to produce it and maybe get some income for his family or at least allow the product to be named as a Gary Dodd design.

[S Clark]

I think Danny R has some of the schematics.  I know Charlie Cocci has some. 
They could probably be produced with time and money.   

[Nick B]

I think Danny R has some of the schematics.  I know Charlie Cocci has some. 
They could probably be produced with time and money.   

That would be good. It's nice there are at least remnants of what Gary designed. I don't know who Charlie Cocci is.

[steve]

Well, all of that Dodd gear is still top of the line stuff.  Just for grins, I was looking around for a set of his Dodd 120 amps.  Found a pair... at about double what they cost new. 

I am not surprised. He had a great reputation as to his products. I understand some areas of his products are sealed/encapsulated so the particulars of his design will remain unknown.

Intellectual property rules.  He did things no one else ever considered.  Gary was brilliant, a great friend and gone way too soon.

Dave,

I get the intellectual property aspect, but I also think it's a shame that products that were so well designed and sounded so good cannot be replicated. How nice it would've been if Gary had made an arrangement with someone else to produce it and maybe get some income for his family or at least allow the product to be named as a Gary Dodd design.

Glad you caught the battery problem in time. Hate to see a very good
component damaged.

"Cannot be replicated", one can reverse engineer if one wished to copy..

Even if the Dodd Preamplifier offered perfect reproduction,
as he personally claimed to me, it was developed and marketed after
another/other brand(s) (which uses a properly designed AC power supply/filtering design).
It is even possible to use newly manufactured vacuum tubes, not expensive nos.

Yes, over the decades I have seen both lead acid and lithium batteries swell, over heat,
and even explode.

I agree, when a design is excellent, manufacturers will not purchase the design rights, nor
even pay for a license to manufacture said design; just continue to manufacture their own
designs, even if inferior. 

Multiples have dared ask for free schematics/parts list (not to repair), attempted
to steal designs. But they will never outright pay, or obtain a license to build a design.

cheers

steve