Great post. I own a Soundstream 10.0 "Class A" amplifier that appears to be a first gen model with the small power resistors stacked one on top the other. I understand a MOD would be to replace them 4 resistors with a comparable BLOCK resistor setup. I understand Soundstream did this mod on subsequent versions of the 10.0 amplifiers power circuit. I notice quite a bit of HEAT is generated through them resistors, they get hot and stay hot so I wonder why theres no FAN in there for one.... also If you do the block resistor mod will that pass the heat/load onto another part of the circuitry. Hmmmmmm.... I am tempted to try this mod as the amp operates as it is but man them power resistors run hot and I can see why Soundstream had to address that problem for the level of amp failures/returns dictated a fix. The SOUND of this amp even on SUBS is remarkable, exquisite reproduction is the "goal" of these "cheater" Class A amps It appears. Cant really be called Class A by old standards but the effort is distinguishable. They sound fuller, crisp clear and they reproduce sound that the typical AB amp lacks it seems. Class D Chainsaw amplifiers have come a long way and thats what I am comparing my Soundstream 10.0 to, a Class D amp, cheap as they come but 700 watts RMS.... 85% efficient... The gives and takes of modern automotive sound systems. So many choices and CHEAP. These are the GLORY DAYS for the CUSTOMER of Autosound. Such great deals out there. Wish I was a kid again.... so I installed an 8 track player into my car in 2022.... Sounds KILLER.... 8 tracks had tremendous dynamic range. They still do in 2022 compared to DIGITAL music.... You are only listening to HALF the music when listening to digital recordings. CLASS ANALOG.... Class A... dismissed.
NJOY/BDBD/2022
Yeah, I own a few.... and yes, EXPENSIVE paperweights for the most part BUT they have a special place in my heart as I have had some of these for 40 years or more even... I actually spent several grand recently on vintage electronics from that time. NOW I gotta learn to REPAIR them and get them to operating in my Firebird... It's why I am here really. I need help any way I can get it it appears. I hope to learn enough to get these back to operating condition safely. My most recent purchase, a FOSGATE PA-250 popped a cap upon powering it up. BOOM... smoky.... And yes I been destroying electronic products for decades... then get em fixed and its back to blowing em up again. I hope to stop blowing up stuff and having to pay the price so.... I gotta LEARN in 2022... a goal. NJOY/BDBD/2022
I had a dremel setup with a STAR WASHER... it became a SAW BLADE in regards to them FORD staggered shaft cups.... I remember struggling with them a LOT before I made that little saw.... after that, BANG.... out in seconds and in goes a bushing to take up the slack. I dont miss working on old Fords. NJOY/BDBD/2022
Heres a YouTube video I made last year of the old Firebird.
In the 80's it was the loudest car in Hawaii. CONCORD powered, later I went KENWOOD as CONCORD.... went downhill... ugggggg. No Regrets with my KENWOOD system but I have a sneaking suspicion that my 4 channel amp is sucking juice even though its turned off. Battery seems low a lot. Its why I am contemplating pulling them KENWOOD amps and swapping in some of my vintage gear. I installed a PIONEER TP 727 8 track player in my car a week ago. I did a PRE AMP MOD like in the good ol days, so yes PRE AMP level out from a 1975 8 track... I used to get paid to do that mod... make DIN cables.... It got too easy once DIN disappeared.... Now a kid can install an amp with ease... Theres WAS a TIME.... when ya HAD to go hunt down an "INSTALLER".... a Rare Breed in the 80's when stereos did not really have RCA outputs. AMPS of them times all DIN inputs... Had to GO IN and FIND em.... with NO tech manual even. I can still wing em in 2022. Some stuff ya dont forget. NJOY/BDBD/2022
Theres the ADS 2001 amplifier and speaker system that predates any other amp product I have researched. In 1972 ADS was founded and shortly after they announced their plans to construct a DC/DC switching power amp for automotive use. By 1973 there were prototypes being sold across America. By 1975 these were in 1200 stores worldwide. This is what I have read in my research on the topic of DC/DC switching power source car amps. ADS claims in advertising to be the inventor of audiophile autosound. The ADS 2001 system is that which they refer to.
Everything I have read and remember from my past leads me to believe this: A/D/S/ - "The inventors of Audiophile Autosound". It was in their advertising campaigns of them times I recall. In 1972 A/D/S/ corporation was founded and shortly thereafter they announced plans to construct a DC/DC high frequency switching True Audiophile 12 volt Amplifier system, to market in America.
That product became whats known in history as the A/D/S/ 2001 amplifier and speaker system, which is recognized as the first commercially available 12 volt audiophile quality amplifier and speaker system ever produced for commercial sale. A/D/S/ will go down in history as being the first to bring DC/DC switching amps to the general public in a commercial sense. Before them, there were early prototypes and one off's being constructed as duly noted. It appears IBM created the IDEA of switching TUBES (1958) and General Motors was first in its use of switching with TRANSISTORS shortly thereafter. Then the GREY AREA. Seems NASA comes into play, and it's not till the late 60's that these power systems enter the commercial markets. There are no less than 7 companies that claim to be first in that regard I have read. Only A/D/S/ as I recall advertised being first.... the INVENTORS.
That product became whats known in history as the A/D/S/ 2001 amplifier and speaker system, which is recognized as the first commercially available 12 volt audiophile quality amplifier and speaker system ever produced for commercial sale. A/D/S/ will go down in history as being the first to bring DC/DC switching amps to the general public in a commercial sense. Before them, there were early prototypes and one off's being constructed as duly noted. It appears IBM created the IDEA of switching TUBES (1958) and General Motors was first in its use of switching with TRANSISTORS shortly thereafter. Then the GREY AREA. Seems NASA comes into play, and it's not till the late 60's that these power systems enter the commercial markets. There are no less than 7 companies that claim to be first in that regard I have read. Only A/D/S/ as I recall advertised being first.... the INVENTORS.
I just watched a SON of POWERPUNCH... used in the box with foam inserts DISAPPEAR for 1000 dollars through BUY IT NOW.... someone did. Could have been me but no. But SOMEONE dropped a cool GRAND.... in 2022... Son of POWERPUNCH was the sequel to the disaster... POWERPUNCH.LOL.
Dang! I just found this website and thread, and it is already a dead thread. Shoot!
I stumbled across this thread while I was searching for a schematic for an ADS 100 power plate. I had that schematic decades ago, but it got sold along with the other schematics when my repair business got sold.
In the early 1980s there was a company in Seattle called Magnolia hi-fi who had been selling car stereos but never installed one. I had been installing them since around 1976 or so and so around ‘81 or ‘82 they hired me to open car stereo installation shops for them. We opened I think it was 5 in all. It was very successful.
anyway, I remember back in the day in the magnolia, hi-fi stores ee would do AB comparisons on all the high-end equipment that they had there and we would use tracks like steely Dan’s Aja, and similar jazz.
So because of Covid, I’m banished to my boat at the marina where I had some ADS 200 e and some other speakers and I was doing steely Dan AB speaker comparisons and then went online and found an ADS P100 on eBay and bought it now I want a schematic again.
I stumbled across this thread while I was searching for a schematic for an ADS 100 power plate. I had that schematic decades ago, but it got sold along with the other schematics when my repair business got sold.
In the early 1980s there was a company in Seattle called Magnolia hi-fi who had been selling car stereos but never installed one. I had been installing them since around 1976 or so and so around ‘81 or ‘82 they hired me to open car stereo installation shops for them. We opened I think it was 5 in all. It was very successful.
anyway, I remember back in the day in the magnolia, hi-fi stores ee would do AB comparisons on all the high-end equipment that they had there and we would use tracks like steely Dan’s Aja, and similar jazz.
So because of Covid, I’m banished to my boat at the marina where I had some ADS 200 e and some other speakers and I was doing steely Dan AB speaker comparisons and then went online and found an ADS P100 on eBay and bought it now I want a schematic again.
hey,
That's cool thanks for the literature. Man, we musta sold and installed between the 5 install shops at least hundreds of those P100 amplifiers.
The thing is built right. I remember Alpine came out with an amp, was it a 3002?? 3008? Can't remember the model, but I sure as hell remember opening those up for cutting traces in several places to reroute and isolate signal and power gnd's. Then we'd jump them with a 100 ohm resistor, aka fosgate to get rid of the ground noise.
Then Nakamichi came to us with their ultra super dooper cassette head units and their 100 watt 2 channel "P100 killer". That damn amp had signal and frame grounds common everywhere inside. Idiots. I was just an installer but I knew not to do that. I became very unpopular with the snobs at Nakamichi when I had to spring the news on them. Their solution: plastic mounting brackets! Float the whole damn thing!
Ahhh,, those were the days.
One day Jim Tweeten, the owners son shows up in the parking lot of the install shop, and starts driving golf balls into the surrounding residential streets with what looked like a 9 iron. That made an impression on me, and anyone in his way to be sure. He pretty much lost my support at that moment.
So I eventually ended up parted with Mag hifi and went to the competition to open a radio/stereo/video repair shop that a few years later I bought for $6k and opened my own shop.. ran that 1988 to 2002 or thereabouts. I was looking back this summer and ran some stats.. we were doing 55 chassis repairs/day, over 17,000 annually. That's abuncha solder work! $987,350.00 gross. damn! missed the magic million by 13k.
I left hifi/video for food service in no small part due to ******* policies like from Sony and others, so went into food service on account their electronics gear supports a money making activity, so fixing their stuff has a lot of advantages.$$$. Been doing that since 2006. Plus they love me, from their perspective (and my co workers) I am the miracle electronics tech.
The Kenwood rep was a lot of fun, he'd bring the new line of amplifiers to my shop and we'd beat the hell out of them. He was tickled when I built a jig to bridge those into mono, we'd run those till they smoked. That guy knew exactly what his stuff could do (over some beers in a closed up for the night warranty station).
One time we added a second voice coil to a tweeter and used his amplfiers to make a hi freq servo/amp/speaker. That was fun.
Another time A guy who designed speakers for Speaker Lab was trying to make digital audio recordings of his guitar playing on his HK VCR and his guitar amp delivered 120vac along the VCR signal ground. Blew snot out of it. He had a lot invested so I went through the whole thing and fixed it. I shouldn't have, it was a LOT of work, but to his credit in return he designed and built never sold speaker lab.1 bench reference speaker pairs for my shop benches, those were sweet! Still have one pair.
Sorry to blather on.. I guess I must feel a bit guilty for bailing out of an industry that treated me pretty good overall and I enjoyed it a lot.
Sooo... who has that P100 skin? (schematic)..
Hmmmmmm?
;^)
jg
That's cool thanks for the literature. Man, we musta sold and installed between the 5 install shops at least hundreds of those P100 amplifiers.
The thing is built right. I remember Alpine came out with an amp, was it a 3002?? 3008? Can't remember the model, but I sure as hell remember opening those up for cutting traces in several places to reroute and isolate signal and power gnd's. Then we'd jump them with a 100 ohm resistor, aka fosgate to get rid of the ground noise.
Then Nakamichi came to us with their ultra super dooper cassette head units and their 100 watt 2 channel "P100 killer". That damn amp had signal and frame grounds common everywhere inside. Idiots. I was just an installer but I knew not to do that. I became very unpopular with the snobs at Nakamichi when I had to spring the news on them. Their solution: plastic mounting brackets! Float the whole damn thing!
Ahhh,, those were the days.
One day Jim Tweeten, the owners son shows up in the parking lot of the install shop, and starts driving golf balls into the surrounding residential streets with what looked like a 9 iron. That made an impression on me, and anyone in his way to be sure. He pretty much lost my support at that moment.
So I eventually ended up parted with Mag hifi and went to the competition to open a radio/stereo/video repair shop that a few years later I bought for $6k and opened my own shop.. ran that 1988 to 2002 or thereabouts. I was looking back this summer and ran some stats.. we were doing 55 chassis repairs/day, over 17,000 annually. That's abuncha solder work! $987,350.00 gross. damn! missed the magic million by 13k.
I left hifi/video for food service in no small part due to ******* policies like from Sony and others, so went into food service on account their electronics gear supports a money making activity, so fixing their stuff has a lot of advantages.$$$. Been doing that since 2006. Plus they love me, from their perspective (and my co workers) I am the miracle electronics tech.
The Kenwood rep was a lot of fun, he'd bring the new line of amplifiers to my shop and we'd beat the hell out of them. He was tickled when I built a jig to bridge those into mono, we'd run those till they smoked. That guy knew exactly what his stuff could do (over some beers in a closed up for the night warranty station).
One time we added a second voice coil to a tweeter and used his amplfiers to make a hi freq servo/amp/speaker. That was fun.
Another time A guy who designed speakers for Speaker Lab was trying to make digital audio recordings of his guitar playing on his HK VCR and his guitar amp delivered 120vac along the VCR signal ground. Blew snot out of it. He had a lot invested so I went through the whole thing and fixed it. I shouldn't have, it was a LOT of work, but to his credit in return he designed and built never sold speaker lab.1 bench reference speaker pairs for my shop benches, those were sweet! Still have one pair.
Sorry to blather on.. I guess I must feel a bit guilty for bailing out of an industry that treated me pretty good overall and I enjoyed it a lot.
Sooo... who has that P100 skin? (schematic)..
Hmmmmmm?
;^)
jg
I have a Lafayette Kt615 you hear the difference from tube to transistor amps.
It could be the tube uses higher voltage.
So if big in audio try a good tube amp
Guitar owners like the Lafayette kt615
I did see this from 2008
My Lafayette kt615 I got new in a kit.
Dave
Tube amps are a completely different animal. For a solid state (transistor) amplifier using global feedback, the output of the amplifier will simply be an amplified version of the input to the amplifier section. Even the speaker load will make no difference due to the global feedback. Even the components used in the amp, like the various transistors, make no difference in the sound as long as they are good quality parts.
A tube amp with a transformer output never (as far as I know) uses global feedback from the speaker output. It can use local feedback in various stages but that's different. For a tube amp, the components used can make as much of a difference as the circuit they're in. Change the tubes (even with identical part numbers) and the amp sound can change significantly. The transformer on the output can also make a huge difference in the sound. A tube amp can, with one pair of speakers, sound wonderful but awful with a different pair of speaker and the speakers that sounded awful with that tube amp may sound wonderful on a different tube amp.
A tube amp with a transformer output never (as far as I know) uses global feedback from the speaker output. It can use local feedback in various stages but that's different. For a tube amp, the components used can make as much of a difference as the circuit they're in. Change the tubes (even with identical part numbers) and the amp sound can change significantly. The transformer on the output can also make a huge difference in the sound. A tube amp can, with one pair of speakers, sound wonderful but awful with a different pair of speaker and the speakers that sounded awful with that tube amp may sound wonderful on a different tube amp.
Hmmmm,
Anyone else noticed that huge rise in Harley Davidson sales in the last, what? two decades or so?
The boomers came into some real money. Heck, even I have a 44' sailing yacht, a FAA certified flying boat (in annual), and a nice street ride bike.. and it's all paid for.. not bad for a drop out. (who needs college when in 1984 you could make 50 or 60k in hi-fi?). I had local college engineering students quitting school to come work with us too. Who could blame them? They're lucky to get 30k outta college then.
Now we want what we could not afford then, and we can afford it, before it's too late.
jg
Anyone else noticed that huge rise in Harley Davidson sales in the last, what? two decades or so?
The boomers came into some real money. Heck, even I have a 44' sailing yacht, a FAA certified flying boat (in annual), and a nice street ride bike.. and it's all paid for.. not bad for a drop out. (who needs college when in 1984 you could make 50 or 60k in hi-fi?). I had local college engineering students quitting school to come work with us too. Who could blame them? They're lucky to get 30k outta college then.
Now we want what we could not afford then, and we can afford it, before it's too late.
jg
You actually want to fix that? I had one in '85, with a 214 cassette deck. Kind of a noisy critter, but I did like the looks of it.
The only Proton schematic I have is the 250 amp. And IIRC, the 740 receiver schematic is around here somewhere, too.
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Regarding $ cost, vs. performance, I would put my MACKIE M-1400 power amp up against ANY vintage competitor.
The MACKIE would win 'hands down' > Design, Power, Bandwidth Linearity, Current, Damping Factor and Reliability.