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Why is my Ampeg SVT 3 Pro outperforming a SWR SM-900??

Discussion in 'Amps and Cabs [BG]' started by NapBass, Jan 17, 2005.

  1. NapBass


    Jan 17, 2005
    I’m currently playing an Ampeg SVT3 Pro head along with 2 Mesa/Boogie cabs – 1 x 15 and a 2 x 10. I’ve been playing 2-3 times a week for the last 5 years through this rig and have always been happy with the sound. Recently I noticed my amp seemed like it wasn’t functioning at 100%, so I decided to demo a SWR SM-900. I’d done a lot of reading on various message boards and had only ever read positive reviews of the SM-900.

    I played one night using the SM-900 with my Boogie cabs, and I was really disappointed with the sound I was getting. It seemed like the amp wasn’t producing the power or clarity that my Ampeg produced (even functioning at less than 100%). I had to play the SM-900 at a much higher level than my Ampeg to produce the volume of sound I’m used to. This really confused me because the SM-900 claims to produce 900 watts @ 4 ohms, while my Ampeg is rated at only 450 watts @ 4 ohms.

    While I was disappointed in the performance of the SM-900, I wasn’t ready to give up on it because of all the positive feedback I had read about the amp and because I was playing it in a room I was unfamiliar with. I decided to try the amp again in a room I play weekly, so I’m very familiar with the acoustics. This time I took both amps to the job to hear them side-by-side. I set my rig up so I could easily switch the speakers from one amp to the other, and I played through each amp, switching back and forth several times. I was surprised to find that the Ampeg produced a punchier, cleaner, and louder sound.

    Again, I’ve only ever read and heard rave reviews of the SM-900, so I started asking around to find any information that would explain the results I was getting. The only info that made any sense to me came from a bass player who owns several rigs – SWR, Eden, Ampeg to list a few. He told me he loves his SWR rig, but ONLY WITH SWR CABINETS. I’m not big into the technical specs of amps. I know the basics but pretty much rely on my ear to determine how I feel about gear. He explained that SWR tweaks their amps to run at a slightly different ohm rating, which the SWR cabinets are built for. This is why he says the amp sounds great through SWR cabinets.

    So I am going to try the amp with SWR cabinets – probably a 1 x 15 and a 4 x 10. BUT MY REAL QUESTION IS: Is he right regarding the SWR gear? It’s possible I’m setting the amp up incorrectly or I picked up a defective amp to demo. Any info would be helpful. Thanks!!!
  2. Dave Siff

    Dave Siff Supporting Member

    I used to have an SM-900, which I ran through Aguilar cabinets, and it sounded great. But, it could be true that SWR amps are designed to sound best through SWR cabinets.. it would certainly make sense.
  3. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    How were the gains set on both amps? Putting the knobs in the same position does not mean you're comparing things fairly. If one amp is set with more gain than the other (which is possible even on a lower powered amp set with the same knob positions as a higher powered amp) then the amp with more gain will always sound better, as long as it isn't running into clipping.

  4. IvanMike

    IvanMike Player Characters fear me... Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    the first question is; how did you have the cabinets hooked up to the swr?

    if you ran the swr in stereo mode each cabinet got 220 watts (thats what the 900 puts out into 8 ohms per side)

    if you ran it in bridge mono mode you sent about 800 or so watts into the cabs, so at most you doubled your wattage and should have gotten a theoretical maximum of a 3 dB increase from the swr, which is a just noticeable increase in volume.

    the real test to see what's what is to do some preamp swapping (running the line out/effects send of one amp into the poweramp in/effects return of the other and seeing how that sounds compared to the internal preamp, and then switch the experiment). this will tell you if its the preamp voicing or the actual wattage of the amp that's allowing it to cut thru.

    the idea that swr amps are designed to only sound good with swr cabs is pure bunk. the original swr pre was designed a long time before the 1st cab was. the idea that they're tweaked to run at a certain ohm rating is even more silly. solid state poweramps run at any ohm rating at or below their stated minimum. the gaps are tight between 2 ohms and 4 ohms on the 900, but that's not going to affect tone.

    Try turning the aural enhancer all the way off (left). this will give you a thicker, more traditional sound. SWR amps also tend to have a bit of a dip in the 200 hZ range, using the semi parametric eq to bump that frequency just a bit can help cut thru with a "thicker" tone. Also, a good part of the ampeg mojo seems to be high mids. you can try bumping somewhere around 2 K a tiny bit. To give my swr an "ampeg-ish" vibe, or just to warm up the tone i often use a sans amp bass di.

    of course, you can just get yourself an ampeg pre and a stewart 2.1 or qsc plx 2402 power amp and get LOUD :D

    FWIW, i've used an swr pre and several other preamps for years. using the same poweramp whith the swr and other preamps, i have always found the swr to cut thru like a mother, its just a little chilly sometimes
  5. CLJMB

    CLJMB Supporting Member

    Jan 4, 2005
    North Alabama
    I had a mid-90s SM -900 that I used through two Goliath II cabs, and I had the same issues. The lack of low-mid grunt that SWR stuff has makes it difficult to cut through on stage. Helps to keep the Aural Enhancer off and boost low mids in the 200hz range. I ended up going with another rig after struggling with the SWR for about six months. :rollno:
  6. NapBass


    Jan 17, 2005
    Realizing that the amps are totally different, I attempted to set them at the same "levels". Set both master volumes at full and both input gains to 3 o'clock.
  7. NapBass


    Jan 17, 2005
    Additonally - ran the cabs together - 4 ohms - ran the SM-900 in bridge mono mode
  8. IvanMike

    IvanMike Player Characters fear me... Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    thought so
    ok go reread my initial post, i edited it and added some more stuff when i though of it :D
  9. Eldermike


    Jul 27, 2004
    I have played my 3 pro though ampeg, Eden, SWR cabs. My current cab inventory is an Eden 4 x 10, an older SWR 4x 10 and a SWR 2 x 10. I hope ampeg keeps the 3 pro head in the line, and unchanged.

    I recently tried to find a replacement for my 3 pro, fearing that it will let me down due to age. The replacement is going to be another 3 pro.
  10. NapBass


    Jan 17, 2005
    If I don't get the SM-900, I'm probably going to get a SVT 4 Pro. I want to have the option of a 2 ohm load which the 3 Pro doesn't offer.
  11. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    I suspect that's the problem. Ignore the knob positions and just see how loud the amps will go before clipping or sounding distorted. At the end of the day the difference in power is not that great, not much more than 3dB, which can easily be overwhelmed by unfavourable EQ. However, set to produce similar sounds, I'd expect you to be able to turn the SWR up louder before it clips.

    Knob positions mean very little even when calibrated in dB, and almost nothing when uncalibrated - my SWR Grand Prix and QSC PLX 3002 may not seem that loud with my default settings but as I dig in more it just gets louder and louder and louder with no compression or distortion. Whilst with similar settings on my Peavey combo it was deafening when played normally but it couldn't go any louder when I played harder, it was already up against the limits of the power amp despite the knobs not being cranked that far.

  12. DaveAceofBass

    DaveAceofBass Supporting Member

    Feb 20, 2004
    Charlotte, NC
    SM-900 is way better than SM-500. SVT-3 is also better than SM-500. But best of all--Aguilar. In your price range, just get the AG500 and be done with it.
  13. IvanMike

    IvanMike Player Characters fear me... Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    oh i just recalled, if you set the eq selector on the 900 to both (i think it's 1&2 or something like that), you get about a 4 dB increase in the preamp section.

    before you get an svt 4 pro i'd do extensive comparison of it with your 3 pro in terms of tone and power. if you don't mind the extra size, you might be happiest by keeping your 3 a a preamp/amp for smaller gigs, and using a stewart 2.1 or qsc plx amp as extra power for it.

    or, you could get an aggie db-750. IMO, the ag-500 is nice, but the db-750 has a very ampeg-ish vibe and is LOUD as hades. scary loud.
  14. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    South Shore MA
    Ampegs just have a woolier sound out of the box that make them sound louder IMO. And also, SWR heads are a beeeyatch to get used to. FWIW I run an SM-900 into 1 Aguilar 410 at 4 ohms and have never been in a situation where I am lacking in volume, even in punk/garage aka deaf bands.

    My eq: I use one band, gain around 4 or 5, AE at noon or 11 o'clock, bass +2, band one boosting 6db at 120 hz, band 2 boosting 6 db around 250hz, treble flat. My basses are a Stingray 5, Sterling, Fender P and a Carvin kit. I run the active basses with just a little goose on the bass knob, plus treble if the strings are shot, the Fender runs with the tone wide open. Works for me, may or may not for you.

    All that said, as much as I like SWR heads they aren't for everyone. Maybe you're just an Ampeg person tonally speaking.
  15. Bass.


    Jan 23, 2006
    San Diego
    I wanted to re-open this thread... Because i am having problems with my sm-900!

    i'm playing a combo... 60 watt crate which seems to outperform! what the heck could be the problem... im using the bridge mode (with the banana plugs) i am so confused!

    should i take it in and get it checked out or is it just something you guys think i can fix? AND it should be mentioned that it got louder before! so i think somethign definitely happened

  16. Bass.


    Jan 23, 2006
    San Diego
    any help??
  17. anderbass


    Dec 20, 2005
    Phoenix. Az.
  18. bobyoung53

    bobyoung53 Supporting Member

    Aug 29, 2004
    Millbury Ma.
    Because it's an Ampeg, Ampegs have been here since the forties and have always sounded good and have always been the best and have lasted the longest. I have a 1959 Ampeg bassamp I use for practice, it keeps going and going, in two years it will be 50 years old, I also have a couple of 30 year old SVT's with all original speakers and correct tubes that keep going and going, also got a 30 year old B-15S that, yeah you guessed it. When you get sick of the amp of the month club, get an Ampeg.;)