I just got an Ampeg SVP CL preamp and a Stewart PA-1000 power amp (basically the world 1.2 now) and have questions mainly about the reliablility of the Stewart. I also have an iAMP 500 that I can just use the power amp section through the effects return if need be. Any thoughts and comments on stewart reliability would be great. Thanks.
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Anyone have opinions about Stewart Power Amps?
- Thread starter sadowskyschmaus
- Start date
Jim Carr
Dr. Jim
- Jan 21, 2006
- 16,223
- 7,613
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- Disclosures
- fEARful Kool-Aid dispensing liberal academic card-carrying union member Musicians Local 72-147
A friend has a 2.1 world. It sounds great. However, his Read Purity Pre-amp, Bergie Cab, Sadowsky P/J, and fine playing skill are also obviously part of his really great tone. 
I love my Stewart World 2.1. I like it's dual seperate power supply arrangement (only sharing the AC cord).
So far very reliable. Only problem I've encounted is connecting it to an inexpensive rack power conditioner (since replaced with a higher powered one).
Sometimes I can hear the fan noise but that's when everyone is quiet.
Great sound! Plenty of power!
So far very reliable. Only problem I've encounted is connecting it to an inexpensive rack power conditioner (since replaced with a higher powered one).
Sometimes I can hear the fan noise but that's when everyone is quiet.
Great sound! Plenty of power!
I own a pair of World 2.1 amps... 'nuff said?
I only use one at a time... and often, just one channel. Better to have watts and not need 'em than to need 'em and not have 'em.
Oh yeah: in five+ years of gigging once a week I've never had a problem with my Stews.
I only use one at a time... and often, just one channel. Better to have watts and not need 'em than to need 'em and not have 'em.
Oh yeah: in five+ years of gigging once a week I've never had a problem with my Stews.
I owned two stewart 1.2 amps. used them bridged in two different rigs. light, powerfull, only downside was possibly small wattage in stereo mode 350w ea. or 1000 mono @ 4 ohms. I used them for bass guitar, I wouldn't use them for studio amp (harsh mids) maybe o.k. for PA. If I needed another 1000w+ mono amp its the first amp I'd look for...
I use the 2.1 when I need that much muscle, and I've not had any problems at all. I've heard that the (passively cooled) 1.2 can struggle with thermal shut-down, but that's not been an issue for me at all with the 2.1
My 1.2 has been an incredible performer. I leave a half rack space above and below it, and I never have problems.
If you want light weight wattage, they are a good choice
If you want light weight wattage, they are a good choice
Thanks guys...I have heard of the 1.2 going into thermal shut down ofter, but as the last guy said, I think if you leave open space around it in your rack it should be good. Maybe I should just get a clip on fan or two to hook onto my rack also? SO that being said...what preamps are you guys using with them and has anyone tried the ampeg svp cl with a stewart?
I have an iAmp 800 and I know you had one also. I just took it to an outdoor festival gig last weekend and ran it with a 2.67 ohm load. Since it is an iAmp, I had it turned up pretty loud - about 7.5 or 8 on the output level. I was askng about as much of an iAmp 800 as one could reasonably ask.
The tone killed, but I had the exact same problem you describe above with peak power. I definitely found the limiter a bunch, and it was mildly disconcerting. On the other hand, the iAmp was totally cool to the touch after the 90 minute outdoor set.
So, back to the Stewart topic. I wonder if we are really just identifying an inherent issue with peak power requirements in these class D amps. They sure are light, which is awesome, and they really sound great too.
I'm sure it did. I recall your other thread about this vaguely, but what preamp did you go with again? An FX-1, was it?
i run a variety of pres, including the svp-cl, through my stewart 1.6. i love it. i've got at least 100 hours worth of gigs on it and who knows how many more from rehearsals and just messing around. zero complaints. i love it.
the ampeg pre absolutely KILLS through this amp!
the ampeg pre absolutely KILLS through this amp!
I run my Alembic F-1X into a Stewart World 2.1. Great sound, its's capable of going blazingly loud, nice deep lows and best of all it weighs 16 lbs. I used to use a lead sled and didn't notice loss on the bottom end to justify hauling around a big heavy tank when the Stew got the job done just fine.
I've experienced a shutdown exactly once in 400+ gigs with mine - a result of patching the Stewart's power cable into a Furman power conditioner. Plugging directly into a wall outlet is an absolute must with these switching amps. A power conditioner will merely act as a valve limiting the amount of juice the amp needs to perform. That was an important lesson to learn on a gig, but a good one!
Lonnybass
I've experienced a shutdown exactly once in 400+ gigs with mine - a result of patching the Stewart's power cable into a Furman power conditioner. Plugging directly into a wall outlet is an absolute must with these switching amps. A power conditioner will merely act as a valve limiting the amount of juice the amp needs to perform. That was an important lesson to learn on a gig, but a good one!
Lonnybass
Well, that's the rub then, isn't it? The weight given the quality of the sound is the upside on switching amps, we all seem to agree. The requirement for a stable, strong power supply in order to avoid shutdown issues is a bit of a problem, since most of us have very little control over that from gig to gig.
It's easy enough to blow off the power conditioner, but we can't always ensure that we have a good wall outlet to ourselves. Sometimes I find that we are powering the whole band off the same circuit that is shared with the refrigerator, the ice maker, and the neon Budweiser sign - which, I venture, would have a similar effect on the quality of the power.
True. I've decided to protect myself from such situations by carrying at least two heavy-grade extension cords in case a long run for power is needed. My bigger concern would be line noise and interference in the DI coming from all those other gadgets!
Lonnybass
Stewart 2.1 with SansAmp RBI. No issues with upright or electric. I use to bridge it... But now I mostly run one channel into an 8ohm 410, 212, 215 or 208. I really enjoy it.
I don't know about Stewart amps, but most all switching power supplies are regulated. They handle a wide variation in input voltage with no problems. There's should be no need for a dedicated outlet. Even if you had a wall outlet there's no guarantee the wall wiring isn't screwy or the beer cooler isn't on the same circuit.
No power conditioner with Stewarts.
No power conditioner with just about any power amp.
Most good ones have sufficient built-in protection.
All you're doing by plugging into a power conditioner is limiting the performance of your amp.
Lonnybass
No power conditioner with just about any power amp.
Most good ones have sufficient built-in protection.
All you're doing by plugging into a power conditioner is limiting the performance of your amp.
Lonnybass
+1
Stewart will tell you there's no need, and depending on the nature of the conditioner, it could actually hurt the amp as it sometimes needs large surges of current draw to "recharge", which the conditioner could interfere with. Mainly it can do no good for the power amp, so there's no need anyway.
I've pushed the crap out of my World 2.1 on blistering hot days with no breeze to speak of and not had any problems at all.
However, I will say I find one thing about them annoying. If power is lost, they have that power-on delay which has slightly bit me a couple times. I briefly lost power (due to some production jackassery behind the stage... rare, but it happens) and we had to wait to start the next song because of it.
Overall, minor niggle, but it's there.
Other than that, it's the only lightweight amp I like for bass currently, tho I will probably revisit QSC PLX at some point just because of the feature set and the fact they fit smaller racks.
On a side note, I also had an iAmp 800, and also had the OCL shutdown problems, and that was a big part of why I got rid of it. The dead last thing you want happening during a crescendo is the entire bottom dropping out of the band. IMHO, that's intolerable.
