PG vs Soundstream

[raffex]

always a big fan of PG including ZX, M, MS series amps .. love them !!!

been seeing a lot of soundstream amps on ebay and ampguts.

what do you guys think. the reference/rubicon seem like decent equipment. as good as M/MS/ZX ?

[twisted]

i love o/s soundstream stuff!!! gobs of of clean power and way under rated.

[Eric D]

I personally think Soundstream amps sound better than PG amps by a small amount, but their power supplies are under built, and prone to failure. I have always been a fan of the clean look of Soundstream amps, and I especially like their terminals (which are for the most part indestructible).

[raffex]

suprised some of you actually like them MORE than PG ?

Anymore care to comment on design/architecture vs PG. especially the older models. eg. rubicon

[1moreamp]

Well I disagree with Doc < nothing personal Doc>on the terminals as i have seen then cross threaded and I have seen then broken and the slot ripped out of the threaded inserts and the plastic protective sleeves melted and striped out by electric screwdrivers , bear in mind all these parts are available from JandRelctronics on e-bay. Jaime was there production manager for about 10 years. Call him if you need parts hes local to me and a great fella to do business with. Tell him I sent you, as we go back a ways. Also bear in mind that people can destroy anything, even fool proof terminals.< Please no offense Doc>

The Rubicons were the last stage of the Reference line. very similar but Improved inside in many ways after the long run of the Ref series, they modified the design to the Rubicon series. Bullet proof output stage redesign with High powered transistors like PG amps instead of teeny weeny TIP 102/107 Darlington outputs.
I have seen a bunch of the REF amps run at one ohm, and you DON'T want to do that to these amps. I post a pic of a Ref run at one later in this thread, you'll love it .

And Doc is right the power supply is a bit under designed in the Ref line they suffer from failed dual diodes on a regular basis, and sometimes complete power supply burn out. The dual diodes are stacked for high current and they don't current share well under stress even though they were all curved traced to spec before being installed in the amps they fail regularly at low ohm loads. I stock these in bags of 100 pieces, just to have enough stock on hand.
There toroid was hand wound I think also as they like to sing with the music, and they short out and need to be reworked on all models when on the bench. The 16 volt rails like to fail and the amps with three terminal regulators need to be shimmed to spec to get the case hold down screw to clamp it properly, or they fail.
The Tip 102/107 outputs need to be matched in sets by gain and bias idle current draw when installed as these Very large array's of outputs will not survive if they are not match for current sharing related issues.
The Entire Ref line are all low voltage high current amps, so the current sharing issues and the very large array's of devices is also its Achilles heal as far as durability goes.

Nice looking and well accepted locally and elsewhere for both SQ and styling, they do have there quirks inside, and are not intended for the beginner tech, as these amps Require a dedicated and steady hand on the repair bench to bring them back to life.

The Rub line had a bunch of these issues Engineered out, the output stage and FEB driver cards were all redesigned and are much better IMO engineering wise. But here again the Power supply is still a weakness even in this design, and they are using the biggest Mosfets available in the TO-220 package, but the power supply's still fail as a stop gap to turning your trunk into a BBQ pit.

Some folks say the Rub's don't sound as nice as the Ref's did, but IMO the Rubs are better built then the Ref's as it should be as they had years of Ref failures to guide them to a better design. My good friend Lance worked for them for 14 years during the Ref Rub line. He now works for Intel.

Well I hope I answered many of your questions about Sound Stream Ref and Rub amps. With the info above any local tech should be able to keep you running for years to come in both of these amps series. ....

[marko]

i just bought 3 ref300's that need repairing, ss is new teritory for me but i always fancied some so snapped these 3 up for beer money they come with a spare board and a few parts too so should be fun, picking them up next week...

may need your advice at some point cecil

[1moreamp]

Sure thing, I think I might know those three amps already. look at the twin 39 or 390?? ohm resistors in the 16 volt rails they are usually the bad boys that gave up, You can't miss them they are big and brown from heat, and in the center of the board near the RCA end on the amp. The Ref 300 failures are well documented as they all fail these resistors when driving woofers and low ohms C

[marko]

Sure thing, I think I might know those three amps already. look at the twin 39 or 390?? ohm resistors in the 16 volt rails they are usually the bad boys that gave up, You can't miss them they are big and brown from heat, and in the center of the board near the RCA end on the amp. The Ref 300 failures are well documented as they all fail these resistors when driving woofers and low ohms C

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :IT&ih=018

bought them off graeme, the guy with the twin cyclones off this forum, they have had the 390uf caps changed once before.....

[marko]

just had a quick look at the ref300's i got yesterday, 2 of them have duff 10ohm resisters (near the 390 ones), and one of the 390ohm resisters has a leg de-soldered from the board, still reading 390 ohms but no idea why this has happened, maybe a bad solder! also one of the big 0.27ohm resisters is out near the outputs. as for the 3rd amp, i couldn't find anything wrong with the resisiters yet, have to dig deeper on that one!

[HoseHead]

I have a BIN Tarantula 500.4. Physically a monster amp that was purchased for the Lincoln in my sigpic. Time, time, time.......Never enough time.

http://ampguts.realmofexcursion.com/Sou ... tula_5004/

Any comments or experiences with these? Your time is appreciated.

Bruce

[1moreamp]

If you mean me, I have not seen any of these come across my bench. My long time friend Lance L. < X- SoundStream engineer> say they make the 0 gauge wire jump on the test table < Very high current draw>

From the pics it look well made enough. I like the dual power supplies < less bridging issues with this design. Looks like Sanken or Kenwood LAPT outputs so a big plus there.
I see they Mimic PPI by using big Mylar film input caps. If your ever looking to bypass the front-end there the inputs to the main amps are on those 4 big brown Mylar caps.

It probably could give a 200.4 a run for its money but SS likes to run lower rail voltage so I figure that why its not rated at a higher power level but that would tend to make it more reliable also.

I would grab it if the price was right. Even if I did not like it it would resell easily. I hope you got a good price, I give it thumbs up until I see or hear bad about it...C

[marko]

after swapping a resister out (10ohm) and resoldering that leg of the 390ohmer back in i now have one fully functioning amp

the other 2 have the fault led on and a flashing high power/high current led...

i need to do a bit more shopping with jandrelectronics

how do i test the duel diodes? i gues they have to be removed?

mark.

[1moreamp]

how do i test the duel diodes? i gues they have to be removed?

mark.

I lift the center pin and use it as a common for the two outer pins. In circuit they run these in arrays so one shorted unit will make them all read shorted, lifting the center pin gets around this issue. This is a very common failure on these amps, Jaime at JandR has these rare and special diodes....C

[marko]

i was thinking of these, got a bit confused, some of them look to have been changed at some point...

[1moreamp]

Those will read fine in circuit they are just 15 volt zeners, and someone has replaced them with a higher wattage version I.E. the glass red one is not stock, but higher wattage never hurts.

This is the main failure of these 300's I have seen this too many times. Its a week point that was designed to fail before the rest of the amp turns into a cinder.
On larger Ref amps they use 3 terminal regulators under the board. You could mod this up to that setup, but the cases of 3 terminal regulators are slimmer then regular transistors so you would need to add shim stock to make then press against the case properly. SS had a issue with this also on the REF series.

These amps sound good but they had their share of issues also, and this applies to the entire REF series. The RUB series had major changes to resolve these issues, but the power supply would still give out on them also.

But only when you were doing something you weren't supposed to be doing with them like running 1 ohm woofer loads with reckless abandon

[Stewart]

As I remember one of the problems with the Soundstream amps was the way they clamped the output devices and FETs to the heatsink. I remember a study we did on this method and it was very, very unpredictable.

In any event, from a sound quality respect the SS amps sounded good. I prefer the design work that evolved from the MS (output coils and a little negative feedback) to the Ti line (no output coils, little negative feedback, and complete phase co-herence throughoutt both the voltage amp stage and current amp stage).

With the gains properly matched, the PG amps and old Soundstream amps sounded great, but when pushed into lower impedance loads, the PG amps usually sounded better to my ears. I am sure this is due to the overbuilt powersupplies the PG units have, as well as the triple darlington output stage which supplies tons of current gain at low impedances.
If anyone has a newer Soundstream schematic I would love to see what topologies they are currently using.

[lopezi]

I can say I never had any complaints with my D200II, wish I never sold it....oh well....