Soundstream reference 1000sx

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I just picked up this amp from my distributor in working condition. He gave it to me for a couple of cheap amps I fixed for him worth with the repair charge-for value at less than half the value of this amp < less than this the value of this Reference which I now own.

I wonder if it would finally be worth swapping this amp into my personal system, to replace either a Hifonics Thor X (Zed Audio) or a Soundstream MC140x? I know the MC140x is a bit older, but I believe this Reference amp is using most of the same components at a much larger scale.
 
I pulled the cover off this amp last night to check it through, and it looks fine. Im not sure if the build quality is quite as good as my MC140x, but this 1000sx sure is clean. One thing I noticed is that this amp appears to be using regular opAmps.

Where the MC140x was using some kind of proprietary or possibly higher end 6-pin IC. This IC kind of looked like a baby daddy-long-legs spider; 6-Legged spider opAmp with 3087 on their backs. Looks like this 1000SX is using something different and/or more common. What does the 3087 do?


Does anyone know if this Reference 1000SX is same/better/worse than my MC140x in terms of SQ quality?
 
Thanks guys, this amp works I was just wondering if its better than my others. I ended up not removing my SS MC140x mainly because this SS 1000 and the Hifonics Thor running together would not have been phisically possible for my current install due to space. Instead, I just put this SS 1000sx into my car replacing the HiFonics Thor Gen X (zed). Now my car is running this SS Reference 1000sx on a single 10" sub, and the MC140x is running my front speakers.

I know my 10"sub is the current bottleneck, and has been for some time. I just ordered a pair of Polk MM840dvc 8" woofers which will be installed in about a week,

Before the swap, I put both amps on the bench to measure their output voltages and clenliness on the scope/meter. The first thing I noticed was that the Thor amp clipped at about 50vAC, where as the SS amp's clipping point was about 56vAC, so the SS has about a 10% signal/voltage 'headroom' so it would seem. The main reason I bench tested the amps was so that I could have as close as I could get, match the input/output of both amps. I took measurements of the Thor amp into MS Excel, and then matched the voltages referenced from the Thor which I then set on the SS. Getting the gain set was easy enough, but setting the boost knob was a little tougher. On the Thor amp, the bass boost knob is hard-set at ~45hz and it was set to +9db out of a possible +18. On the SS, the boost frequency is adjustable and maximum of +9db. The width in which the adjustments; were different and therefore made matching exactly between the two amps almost imposible. Wierdism the SS does, is it's sub-sonic filter is slightly proportional to the boost frequency knob; I'd say only about a 20hz difference such that boost at 40hz results in a subsonic filter at 20hz, or boost at 60hz represents a subsonic filter at 40hz. Since I'm running a flat 10" in a cardboard box I rested on 50hz boost at +8db on the SS and forewent frequencies below 30hz because my encloser cannot play them anyway.

All that bench testing was actually quite a waste of time. Once I got the amp in the car, things were completely different to the point where everything had to be completely re-adjusted. The great thing about the SS amp is it has a clipping indicator for when the input is too high and causes the output to clip. In my car, the amp was no-where near clipping coming from the bench. I turned up my HU to highest normal listening volume and then raised the gain until just-before clip indicator signed. From here, the sub started to come to life with being more properly set gain-wise.

I'm still playing with the frequency/boost knobs and crossovers a bit, and everytime I touch it makes the system sound closer to the Thor in terms of brut which makes the stereo sound large.

The best part about this amp is how melow and still extreme it sounds. Like the way I love my MC140x, this 1000sx reference precevably has better control of the sub than the Hifonics Thor X did. Not to say the SS amp is better, but really the comparison is between a 2x125w Thor and a 2x200w SS. The Thor holds the crown in terms of brut/power and that WOT WOW, where the SS is more of a instrument.

I'm honestly not sure which amp I like better. Day 1 and 2 were leaning tward the Thor, but know after getting the SS better dialed-in on Day 3, the SS seems to be better.

I'll be sure to update this in 1~2 weeks after I get my Polk mm840dvc subs on the SS.
 
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Got the Polk mm840dvc subs on this SS now. it sounds really incredible, but almost right away I new I had to do some trickery with the gain knobs and such. I first tried to run the amp in stereo; each channel to one subwoofer. What i found was some discrepencies with the pre-amp controls; gain and Q levels per channel. The controls from left to right do not completely match ultimately meaning that at one frequency the left channel outputed more amplitude, while another frequency the right channel had more amplitude. To get around this, I set the amp to Bridged mode so that just the right channel's controls work the amp. I kept the woofers wired to each channel and just reversed polarity on the left sub to keep the woofers in phase. This still allows the amp to run at 4ohms bridged measrued on my meter from what I can tell (which is 800w, or 400w per woofer). It sounds perfect now and both woofers move perfectly together. I dont really trust 100% how I have it wired right now so if anyone has any precaution please let me know. The amp runs the same temp and likely the same wattage running like this. Sounds amazong. I believe the internally conencted speaker terminals are just that - internally connected while the switch is in this mode. Perhaps soon I'll just re-wire the subs in series to negate any confusion.

If I get this amp back on the bench anytime soon I'll check and make sure all gain/control knobs were inserted with all pots in the same alignment as I think the previous owner might have removed/replaced some of the knobs. In the meantime she sounds lovely and now a bit better than the Hifonics Thor X amplifier.
 
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Several things come to mind after reading your posts.
1. It isn't a fair comparison to the Thor now that you switched subs, unless I missed where you said that you swapped amps back and forth with the new Polks.
2. When wiring the SS 1000, in bridged mode you use Left + and Right +, I think you said you left it wired for stereo mode. The Left channel output is internally inverted in bridged mode, which is why you reversed the leads at the speaker. The Left + becomes the negative terminal in bridged mode. Also, according to the manual, only the Right input and controls are active.
3. Also, according to the manual, mixed mono may also work for your situation where both inputs are active for summed mono output.
4. Are you driving the amp with sub outputs from the head unit? And are they already a summed mono output?
5. If it were me, I would wire the two Polks in parallel, this amp can handle that.

Here is a link to the manual I was looking at - http://www.soundstream.com/manuals/AMP/REFERENCE/r5_7_10s/r5_7_10s.pdf

Oh and just wait until those subs break in, then they sound even better if you can believe that now.
 
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1. True on the thorx. I did not do any swaping of amps with these polk subs. I do feel the SS amp is better than the Thor though, as rating would go, and also the size and component quantities are slightly greater on the SS. I mean, the SS is rated for 200w per channel, and the Thor is 125w per channel; both are likely under-rated clean true power ratings. I'm thinking something like a Boltar X would be of better ratings comparison. I didnt mean to upset any powers from above and just love the Zed made stuff in the end.

2. All true. I like how I only have one gain control for the masses in Bridged mode.
3. I tried Mixed mono, but it enables both gain controls just like stereo mode and discrepencies are present.
4. Yes and Yes. With the amp in bridged mode it is only picking up 1 of the 2 RCAs (Right RCA). Stereo output is not present through the subwoofer RCAs of this Pioneer 3200bt head.
5. On paper it would work. For me I'm more comfortable with it wired in 4ohms bridged. Its 400w clean to each sub which is over-powering the RMS rating. Theres a ton of headroom to go with the way it is wired and everything feels comfortable. This amp loves to run pretty hot btw. I think SS amps are some of the hottest running Class AB amps on the block. My installation does not provide the best/adequate cooling for the amps as stuff is tucked neatly away in underneith compartments to make the installation as stelthy as possible. I had already some problems earlier this year with stabilizing the MC140 so now this 1000sx is being closly monitored also. I've heard horror stories of these old soundstreams burning up bad when pushed to the max rated output/draw.

I'll probably have to turn the gain down again once the woofers break in. Its a little over the top atm.

Everything sounds great. Thanks for the great word.
 
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I apologize on my comment #1, I have no opinion one way or the other on these two amp brands, I wasn't trying to flame ya, Honest!

Since headunit is sending a summed mono output, I agree bridged mode is probably best in your system.

I would think the subs run to their excursion limit before you ran the amp to its limit let alone damage it with sub wired series or parallel. You don't have to set the gain to have 100% of that power on tap.

I could be wrong, but I always preferred to run subs parallel instead of series when ever equipment allows. I always thought there was a slight drop in SPL series vs parallel as well as they are not actually sharing the power exactly equally. Now, in series, you have a certain level of protection if one woofer coil shorts out, all though I can't remember ever having that happen to me. I'm sure sombody will set me straight on those beliefs.

In the end, you should take none of my advice and do what you are comfortable doing. I am just an amateur enthusiast sharing my opinion.
 
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We are on the same adventure. True about SPL limits on series vs parallel due to a parallel configuration possibly providing more power. I think if I went with 10" or 12" subs I'd probably try to wire them for more power. These little 8" subs are great power handlers though dont need very much as they are also efficient and sound great. As it sits even in series I'm almost doubling their RMS capacity rating with 400w each. Some do say though that these Polks should be rated much higher than they are. 1.5inch xMax is what they say can do (.75 one-way).

The installation of this stuff is in a very small sports car; a Nissan 370z with no back seat and the subs are firing upward from the floor to the glass, which is to be covered soon by a grill with carpetting on top of it. The subs are only about 3 feet from the back of my head, where any bottoming-out, clipping, distortion, or even a bad recording is very evident. If these were installed in a trunk or hatch I'd probably conjure up a more aggressive install. As things sit its more volume and punch than I've ever owned before.
 
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i, actually really liked the 1000/500 s/sx amps. bought one nos off a local shop table for $300 when ss closed the doors and pulled all their info, etc, so repairing them was near impossible for me at the time. anywhoo, you are dead nuts right about their abuse limits. they really don't take much abuse at all. i ran the one 1000sx on a pair of first run l7-15's daily @ 2x 2ohm load, and it really put out some serious power. ended up trading it off for a broken 1000s and kicker ix2302 with burned fuse holders. well, within the year, i had it back, blown, allong with a blown 500s... long story short, they do not have real beefy power supply circuits, and are prone to abuse failure. the good news- an upgrade of irf3205's got my 500s to a nice cool and stable condition. btw, x-max is one-way excursion. x-mech is full range. to be completely sure on the way you have it hooked up, running bridged, simply ohm the speaker outputs. 2 of them should read no resistance, in which case, i would feel safe doing the same.
 
That's funny, generally when you abuse (misuse) something it breaks. That has been the problem with Soundstream's old school amps. People would abuse the crap out of them and then get upset when they broke - Duh! I've never damaged a Soundstream amp. I used high quality wiring and operated them in the correct power mode (high current/high power) for the impedance I was trying to drive - never a problem.
 
I didnt think that IRF3205 units in the PS were adequate without some re-work. I thought I read somewhere that the factory selected components although were under-performing to the IRF3205 were selected because of the specifal switching requirements of the SS's high current/ high power modes. If there is a way to use IRF3205 fets then thats a great idea. I find that the PS side of my SS1000sx gets warmer faster than the output bjts. What does this amp use for outputs anyway? TIP102/107?
 
Dr Zeus, I designed both the MC140 and Ref1000s. The circuitry in both amps is the same except the MC140 used TIP142 and TIP147 output transistors and the 1000s uses tIP102 and TIP107 output transtors. They are both Darlington pairs from Texas Instruments, but I found out that the 102's and 107's have better safe operating area than the 142's and 147's. So I switched to them in later designs. there are 1 TIP142 and 1 TIP147 per power amp in the MC140. While the Ref1000s has 9 TIP102 and TIP107 per power amp. if you want to know anything about either one or any of the older Soundstream amps, let me know.
 
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