SM-900 impressions?

Discussion in 'Amps and Cabs [BG]' started by poundround, Apr 16, 2005.

  1. poundround


    Mar 8, 2005
    Lynchburg VA
    A friend of mine wants to sell his SM-900 for $800. He has hardly used it and its been in a rack case. I have a an Eden 410XLT and a Genz Benz 210. Does anyone know if it would be a good match? Im not about to drive 2 hours for nothing.
  2. msquared


    Sep 19, 2004
    Kansas City
    The SM-900 is one of my favorite hybrid heads. $800 is a good price for it. If you don't like it, you can probably sell it on ebay and either break even or make some more off of the sale.
  3. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    +1 great price and easy to e-bay (or here) for the same
  4. embellisher

    embellisher Holy Ghost filled Bass Player Staff Member Supporting Member

    My Peavey BAM does a pretty good impression of one.
  5. Finger Blister

    Finger Blister

    Jul 8, 2003

  6. I used a 900 for a few years a while back. It is a good sounding head (if you like the SWR scooped/sizzle trademark sound). The head (like most SWR stuff) runs VERY hot. When you push it, since the entire amp case acts as a heatsink, it will get really hot to the touch... so, don't cram it in a two space rack... you need to leave a 'rack space' open for adequate cooling. Also, even though the specs say you can run the amp bridged into 4ohms, SWR doesn't recommend it. So, running the amp bridged into the appropriate 8ohm load results in 650 watts RMS. It was plenty loud for me, but you really aren't going to get the 'advertised' 900 watts out of it. Finally, running in stereo mode into two 8ohm cabs sounds VERY weak.... if you are going to do this, you need two 4ohm cabs.

    I've heard a lot of negative reports on 900 reliability through the years, but didn't have any problems with mine. Hope this helps you in your decision.
  7. secretdonkey


    Oct 9, 2002
    Austin, TX
    I kept mine in a two space rack case... yes it ran hot, but never a shutdown or any problem with many a gig with both pre and post clip lights blipping. I don't recall ever reading that SWR advises against running bridged at 4 ohms... you can run 2 ohms in stereo but not bridged... anyway, I ran it at 4 ohms with never a problem. The amp had a few annoying, mainly cosmetic problems from the factory, but was very reliable and survived a six foot drop (in rack case) that warped the front panel without any functional damage.

    That said, I never quite found sonic nirvana with mine, though swapping the preamp tube did help a lot. I thought I was buying more power than I could ever possibly use, but as the above description of my usage should indicate, I was wrong about that.

    Bottom line - a decent amp, workhorse, lots of knobs!!! :hyper:
  8. Akito


    Dec 1, 2003
    Hm I've run mine bridged at 4 ohms way more than any other setting. Mostly because of my Goliath Sr. which is a 4 ohm cab. Odd that the Sm-900 is at the top of their suggested amps for use with the Sr if they don't think bridged 4ohm load is good for the amp. I've also run my 4ohm Schroeder bridged with no issues, and I've run stereo with the Schroeder on the low end and my goliath 2 on the highs and more than kept up with a 50 watt Marshall and drummer from hell. Just some observations from a long time user.
  9. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    I like mine. $800 is a good deal if it is in excellent/mint condition. Make sure you take the time to learn how the pre operates, it is not a plug and play amp by any means (IMO).
  10. peabody

    peabody Supporting Member

    Oct 31, 2002
    La Crosse, WI
    I've done a little research on this head and I'm finding mixed reviews. Although I haven't been able to play through one yet, I have do have a SM-900 on the way in 2 for 1 trade I just made. Since I already have a decent amp set-up (Aguilar DB659 and a Stewart 1.6), I'm not sure if I'll be keeping the SWR or not. I'll have to A/B the two set-ups and see what shakes out. If anyone is looking for one, keep your eyes open as I may be putting it on the block in a few weeks. I'm trading my '76 "A" neck P for a MM Sterling and the SM900, so I may be in the a market for Lakland Bob Glaub (with the narrow neck).
  11. msquared


    Sep 19, 2004
    Kansas City
    Those of you who have changed out the preamp tube, what did you use and what results did you get?
  12. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    The best tone I ever got out of it was with a very old Sylvania from the early 70's (it was pulled from an old Music Man amp). I had to replace it becasue it was really noisy.

    Mesa "russian" tube with a short plate gave made it barky, emphasized the mids, pretty much as with the EH 12ax7 (which is also a Russian tube). Generally more in your face, and I liked it when I was using the head for rock.

    Recently I've settled on the Sovtek LPS (RUssian as well... hmmm) becasue I like the more balanced tone it gives me. Clearer highs and a bigger low end.

    The Sovtek WA sounded simply horrible (thin, anemic tone which was only made worse when the gain was cranked), I tried a JJ/Tesla and it was bland with a seemingly narrow freq response, had a Ruby tube lying around and it was a close second to the WA in the suck factor. Tried a Hughes and Kettner rebranded tube and it was pretty good, don't know what make it was though. I've had very inconsistent results with GT tubes even with the same model designation.

    Do a seach, there are many opinions on the matter with the afficionados leaning towards RCA, Sylvania or GE NOS tubes.
  13. Finger Blister

    Finger Blister

    Jul 8, 2003
    Just some random thoughts and ramblings...

    Best - Price no object:

    Mullard and Amperex - Look for those with Long Plate and D (square) Getter.
    Any Mullard
    Any Amperex

    Best under $25

    ~Sylvania JAN Black Plate 5751 (1980's green print w/'D' Getter)
    or Gold Print / Gold Pin
    ~GE JAN 5751 (1980's green print w/'D' Getter)
    ~GE JAN 5751 (1980's green print w/'Ring' Getter)
    ~GE 5 Star Grey Plate 5751
    ~RCA 5751
    ~Any USA 5751

    +Clean and hard to overdrive.
    +Solid fundemental
    +Balanced midrange
    +Rounded treble with the least amount of 'presence hiss'
    -Not good with a pre preamp boost that slams the tube with gain.
    +The Sweet tube for Clean.

    ~Sylvania NOS Long Plate 12AX7WA (1980's)
    (a stock pre tube of many 70's/early 80's amps, i.e., Fender Blackface and others)
    ~Phillips NOS 12AX7WA
    ~GE Long Plate 12AX7
    ~GE JAN NOS Medium Plate 12AX7WA
    ~Any US made 12AX7

    +Clean and quiet
    +Overdrives with Richness

    +smooths out the SWR High End`

    I do not recommend Asian or Eastern European pre-tubes
    due to poor construction quality and short life.

    Chinese 12AX7A C-9
    +Overdrives well
    +Highest gain
    +Extended High's
    +OEM SWR Tone:
    -Can be Harsh in the High's
    -Can be 'sterile sounding'

    Groove Tubes 12AX7M
    I bought one of these soon after they first came out (5th batch).
    Poor construction.
    Completely different tone.
    Overdrives differently.
    A all together unique tube.
    Sometimes I hate it.
    Sometimes I can't decide.

    I recorded the 12AX7M against:
    *stock SWR tube (GT 12AX7A - Chinese)
    *NOS 5751
    *NOS 12AX7
    so I could listen to each over and over in sequence to
    help me make up my mind.
    The 'M' definitely has some 'dirt' in it's tone, with a slight mid-range bump.
    Once again, the 'M' is a unique tube that doesn't sound like
    anything else, especially not a Mullard.
    One can love it or hate it; so YMMV.

    IMHO Notes:

    Strangely enough I've found that the best sounding tubes have.... either/and/or:

    D Getter's
    Long Plates
    Triple Mica
    Double Getter Support
  14. msquared


    Sep 19, 2004
    Kansas City
    Very interesting. Thanks Finger, that's exactly what I was looking for. Muchly obliged.

  15. Since mine was running so hot at 8ohms I called SWR to ask about taking it down to a 4ohm load bridged (which results in the amp actually seeing a 2ohm load). The tech that I talked to recommended not taking the amp down to 4ohms in bridged mode due to excessive heat and reliability issues.... that's the only info I have. The tech might have been mistaken or was just being very conservative. I have no first hand experience using the 900 at 4ohms. Sounds like others have not had a problem
  16. Finger Blister

    Finger Blister

    Jul 8, 2003
    Very Strange.
    Most of the recommended SWR Cabinet 'match-ups' are 4 ohm loads.

    I've run my Stereo SWR bridged into a 4 ohm cabinet for
    the past 8 years with zero problems.

    If it runs too hot bridged, your idle current maybe too high.
    If so, then both Amps need to be matched to each other and biased.

  17. That's the first thing I checked, and the bias was OK. Again, I'm just quoting what the SWR tech told me. Actually, remember that the 900 is a stereo amp. It's relatively unusual for a stereo amp bridged to accept a 4ohm load, since the actual ohmage that a bridged amp sees is half the ohmage of the cabinet. So, the SWR bridged into 4ohms is actually running at 2ohms. The Eden800 and other 'bridged stereo' amps are only allowed to run at an 8ohm minimum load in bridged mode. The 750, etc. line of SWR amps are mono amps, hence the typical 4ohm load.

    So, basically, the SWR manual is actual saying that the 900 can run down to 2 ohms in bridged mode. I have always been skeptical about amps running at 2ohms, since this is a 'cheap' way for manufacturers to increase the published wattage of their amps. I realize this is changing (the recommended ohmage for the EBS650 is 2ohms, and the iAmp800 has no problem running at 2ohms). However, the SWR900 is a very old design. That all being said, if you guys are running it at 4ohms with no problem... then no problem!!!
  18. Finger Blister

    Finger Blister

    Jul 8, 2003
    Hell of a lot better then their new designs! :D
  19. I agree, but I had an SM-900 and it just didn't do it for me. I sold it and bought an Eden WT-800 and it was night and day. The Eden sounded so much better, and had the punch that i was looking for.
  20. jokerjkny


    Jan 19, 2002
    NY / NJ / PA
    i dig the 900. the EQ sliders and what not are nicely voiced.