Former carver owner now PL

Joined
Nov 15, 2021
Messages
482
Location
near Liverpool, NY
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Lifelong student / listening = bliss
“Better” is too vague.

“as if the musicians are in the room with us” is the goal I strive for.

I think I’m close, but that 100-watt class-A balanced Krell project nags at me… I’m thinking 1000VA per transformer and cost estimate is around $3,000 to complete a pair.

It might just be easier to get a pair of these:

https://benchmarkmedia.com/blogs/re...MIxOK8iuPc9AIVY4JbCh3wOgOoEAAYAiAAEgKh2_D_BwE

Trouble is, that’ll be six grand…
J!m, I am picking up what you are putting down!

And conversely, you certainly seem to be smelling what I stepped in with my project! :0)

****

Part of my personal justification for what I'm trying to accomplish is:

1) Restoration of some equipment that brought me a *lot* of pleasure over a 20+ year period...and then went into storage for 20 more.
(Seems a shame to cart it off to the dump, or let some parts scavenger buy it for pennies/$ and then scatter it into eBay.)

2) Recover/relearn some (some say obsolete) skills that atrophied over the years, as we all moved from component-level troubleshooting to the swap-black-box mentality. At the same time, go from reciting stuff that I've read over the years...to actually proving it to myself in the real-world, for it's one thing to accurately recite something...quite another to actually *believe* what you are talking about. Comes across completely differently to others.

3) Answer the question "How close can I get to the sound of that highly-regarded $6K amp with the old mules that I'm flogging? (Understand that building sleepers with just a touch of reverse-snobbery has *always* appealed to my sense of humor.)

For example, during/immediately after high school my buddies & I certainly appreciated all the beautiful go-faster goodies in all the HotRod magazine articles. But back then, a new Holley 4-barrel was more than a week's pay! And since 2nd Place = 1st Loser, it didn't feel quite right to be watching the poor little rich kid's taillights disappearing into the distance.

But there were a couple of books, that along with some judicious junk-yarding, allowed us to let those Richie Rich's see *us* disappear into the distance:

Q-Jet Doug Roe(opt).jpg bill jenkins chevy racing engine(opt).jpg

The first book was written by a gentleman named Doug Roe, and he was an engineer with GM's Rochester Carburetors. His explanation of every *single* part inside a Quadrajet, charts & graphs of all the jetting, metering rod diameters/tapers, intake-manifold vacuum (aka: power valve) springs for the primary metering rods, etc., was key to our being able to go to the junkyard, identify the right components, pay $25 for the carb, (+ carb kit, float, fuel filter, etc) and end up with the same/better CFM & throttle response than a new Holley costing up to 10x as much! (And if they looked under our hood & exclaimed "Quadrabog" ...we knew that the hook had been set, and our quarry had no idea what was in store for them. :0)

And then the 2nd book was written by Bill 'Grumpy' Jenkins, and once you learned that the 'double bump' or 'camel hump' casting marks = big valve heads w/the good combustion chambers...then for cheap money & a little pocket porting we were off to the races. (well, new cam, anti-pump-up lifters that you zero-lashed + 1/8 turn, recurving the distributor with new advance weights & springs, etc., etc.)

You know, it would have been one thing to beat the new "Smokey & the Bandit" look-alike car at school with a similar one with cubic dollars spent on it...but instead, going right on by in a rattle-can primer painted tiny teardrop Chevy Monza with a sharp 355ci small block tuned right to the edge of detonation & driven with the controls set for the heart of the sun? Well, we laughed and laughed until we were choking on our victory meal of Capt'n Crunch & whole milk at 1am back at the house.

Oh my misspent youth. I promised myself I wouldn't talk about this in public. But what are they gonna do? I'm retired now...and the statute of limitations have expired. :)

****

Seriously, I really & truly hope that with enough lurking about the internet, and reading what you guys have been up to, spiced with a little of what Nelson Pass, Blomley, & others have so kindly shared...that we are going to have more fun that we should be allowed to have.

Maybe even make Bob Carver proud! (edit: I think he's already there, thanks to Gepetto & all your work to date! What I was referring to was taking some representative WOPL amps to one of the 'Burning Amp' type get togethers...you know, along the lines of the Engine Masters competition.)

(Which reminds me, elsewhere I want to start a conversation about his infamous 'null circuit' that he used to listen to the *difference* between amplifiers playing the same music simultaneously...and his demonstrated ability to tune one of his amps to sound identical to the ne plus ultra amp he was asked to duplicate.)

The bottom line? If I just skip to the chase scene and buy the amp that delivers the musicians into my living space, then I do get to experience instant gratification. But if I want to *know* how it's done, then I'm going to have to gird for electronic battle & put some serious focus on getting some silk out of my Phase Linear gear.

...And we don't have to win. All we have to do is get as close as Bob did back in the day...and the jokers who never hesitate to deride our stuff on the interwebs by referring to it as 'Flame Linear' will detest us forever.

Perfect! (Insert sh!t-eating grin here.)

****

It's gonna be a lot of fun. And true to form, I will document *both* the successes and the failures. I have nothing to fear, for I have no reputation to defend. Game on! :0)
 
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Joined
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Messages
482
Location
near Liverpool, NY
Tagline
Lifelong student / listening = bliss
Oops -- maybe I should apologize. The above really isn't done these days, especially in the polite circles where audiophiles congregate.

I just got so excited about all this that I reverted to what we used to refer to as "Bench Racing". This was standard practice, especially in flyover country, back in the day. But, a lot of our best projects started with similar amounts of balderdash, 'cuz once you say it in public, it can't be unsaid...or unheard by your buddies/partners in crime.

In the future, I will do my best to keep all of this to the bare minimum! :0)

"If it ain't fun, why do it?"

Cheers --
 
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laatsch55

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Halfbiass...Electron Herder and Backass Woof
Bud, LOVE your attitude. We document everything around here, good, bad and indifferent. I've had some fantastic failures, but a lot was learned by everyone..
Yeah, its gonna be fun..
 

laatsch55

Administrator,
Staff member
Joined
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Messages
74,124
Location
Gillette, Wyo.
Tagline
Halfbiass...Electron Herder and Backass Woof
Oops -- maybe I should apologize. The above really isn't done these days, especially in the polite circles where audiophiles congregate.

I just got so excited about all this that I reverted to what we used to refer to as "Bench Racing". This was standard practice, especially in flyover country, back in the day. But, a lot of our best projects started with similar amounts of balderdash.,. 'cuz once you say it in public, it can't be unsaid...or unheard by your buddies/partners in crime.

In the future, I will do my best to keep all of this to the bare minimum! :0)

"If it ain't fun, why do it?"

Cheers --

No, no, no...for God's sake dont dare change your approach!!
I have stated for years that I love "characters"..ya know, the ones that you can notice in a crowd that ain't like the rest, the ones that make life interesting..don't change man...there are far too few characters left in this world!!!
 
Joined
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Messages
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Location
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Tagline
Lifelong student / listening = bliss
Here's a link to "The Carver Challenge".

Not now...but once I restore/upgrade WOPL my D500s, I really want to recreate Bob's 'null circuit', implement it with a clean, battery-powered state-of-the-art Class A headphone amp (so that I can listen deeper into the null) ...and see what I can learn from listening to the differences between different topology amps, varying amounts of feedback, etc.

I certainly won't learn everything I want to before check-out, but I look forward to cramming just as much as I can into my newfound ability to spend my quality time in my personal laboratory...instead of taking my place in traffic during rush hour.

Enjoy --
 
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J!m

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There’s a saying on the track:

If you’re not crashing, you’re not pushing hard enough.

I just crashed into cones, but they certainly felt my wrath.

And regarding amps: 1500 class -A watts is definitely the big dog. The rich kid who buys the fast production car.

Nelson and Dan have some fantastic designs. Nelson always strives for the simplest circuit that will perform the required task. Dan says damn everything and so what works and sounds best.

Connecting those thoughts: the KSA-50 is touted as the best sounding of the early Krell designs. The later KSA-100, with Doyle the output decices, loses the magic.

So 1500 watts (or horsepower- but I’m a touque guy myself) is attractive, but with 120 devices and an outboard control circuit dialing back the bias when not needed(?) sounds an awful lot like a class AB design in a fancy box. It should be dissipating what, 3500 watts of heat or so at idle?

My plan is much more easily done. Four mono boards from KSA-50’s will be used. Two per chassis. Each chassis will run at high voltage (upper tolerable range) fed by 1000VA transformers. The “left” board will be the “hot” balanced lead and the “right” board will be the “cold” balanced lead. Now we have the JSA-100B monoblock. You will have the 50 watt class-A sound with headroom.
 

J!m

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Here's a link to "The Carver Challenge".

Not now...but once I restore/upgrage WOPL my D500s, I really want to recreate Bob's 'null circuit', implement it with a clean, battery-powered state-of=the=art headphone amp (so that I can listen deeper into the null) ...and see what I can learn from listening to the differences between different topology amps, varying amounts of feedback, etc.

I certainly won't learn everything I want to before check-out, but I look forward to cramming just as much as I can into my newfound abiilty to spend my quality time in my personal laboratory...instead of taking my place in traffic during rush hour.

Enjoy --
I just finished building a headphone amp and it would fit your requirements. I’m running out of my old Aragon 47k preamp fed by the Planar 3.

Anyway, you can pick the mix apart- focus on one instrument in the mix and no matter how congested it gets, you can hear the leading and trailing edge of that instrument. It’s pretty amazing.

Designed by Wyn Palmer, who also designed the phono preamp I’m debugging now. He’s a retired PhD that designed op amps in his prior life. Needless to say, he has an understanding of op amps few others can match.

(he also uses a pair of those Benchmark amps and based on their performance he has no intention to design a power amplifier)
 
Joined
Nov 15, 2021
Messages
482
Location
near Liverpool, NY
Tagline
Lifelong student / listening = bliss
There’s a saying on the track:

If you’re not crashing, you’re not pushing hard enough.

I just crashed into cones, but they certainly felt my wrath.

And regarding amps: 1500 class -A watts is definitely the big dog. The rich kid who buys the fast production car.

Nelson and Dan have some fantastic designs. Nelson always strives for the simplest circuit that will perform the required task. Dan says damn everything and so what works and sounds best.

Connecting those thoughts: the KSA-50 is touted as the best sounding of the early Krell designs. The later KSA-100, with Doyle the output decices, loses the magic.

So 1500 watts (or horsepower- but I’m a touque guy myself) is attractive, but with 120 devices and an outboard control circuit dialing back the bias when not needed(?) sounds an awful lot like a class AB design in a fancy box. It should be dissipating what, 3500 watts of heat or so at idle?

My plan is much more easily done. Four mono boards from KSA-50’s will be used. Two per chassis. Each chassis will run at high voltage (upper tolerable range) fed by 1000VA transformers. The “left” board will be the “hot” balanced lead and the “right” board will be the “cold” balanced lead. Now we have the JSA-100B monoblock. You will have the 50 watt class-A sound with headroom.
That's the ticket! I've lurked in a *lot* of places across internet audio-land...but like I said in my introduction, *this* is the place where I felt normal by comparison! (Point in fact, the project you just outlined.) Excellent -- you pull this off, and it becomes "Destination Audio". As in, this weekend I'm gonna drive across several states in order to get a serious listening session in on J!m's new amp that he got all debugged & pressed into service!

That's *exactly* what I'm talkin' about!

I'm gonna have to invest in a bigger popcorn maker...there's good stuff on the horizon!

Go, Dog, Go! :0)
 

J!m

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The quandary is financing.

I can finance my JSA project by selling my Counterpoint amps. But I really like them, and I’d like to have the reference on hand…
 
Joined
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Messages
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Location
near Liverpool, NY
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Lifelong student / listening = bliss
Agreed! If you have something you really enjoy, and has proven to be your go-to listening equipment, you really want to keep it at least until
you have *proven* that the new stuff isn't just new...it's actually a discernable improvement!

You know, the Make Before Break stepping-stone approach. And when it comes to financing, you are preaching to the choir! :)

My 3 hobbies always starved each other. (Audio / Photography / autos) < -- And they only got whatever was left after I did the right
thing by my daughters.

I feel your pain.
 
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