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Tubes for mid.r./high and transistor for low.?

Discussion in 'Amps and Cabs [BG]' started by 6L6, Apr 10, 2005.


  1. 6L6

    6L6

    Apr 7, 2005
    What's your'e opinion about a PA amp. (transistor)
    like qsc or Peavey for the low frequency cabs.
    And tube amp(s) for midrange. ?
    High power tube amp.s are expencive and
    much of the softer tube sound is in the midrange, right ?

    A smaler tube amp. like marshall or peavey aren't that
    hard du get ( for a faire price).
    The same goes for PA amp's.

    Besides midrange speakers are often sensitive (high SPL)
    So 50 - 60 W should be enough.

    The cabinet's can be splitt with an active crossover.
    (som pre amp's have them built in).
     
  2. Aerolithe

    Aerolithe

    Jan 23, 2005
    Columbia, MO
    I've been thinking of doing something similar with a biamp or triamp system since the lows need the most power and itd be easier to do transistors for them, so if anyone has tried this I'd like to know how it went.
     
  3. Transverz

    Transverz believer of the Low End Theory

    May 3, 2004
    Los Angeles, CA
    Thanks for responding in my other post 6L6. You have an interesting idea here for your midrange. Though it won't be a light setup, you probably don't care for that either if you are going for pure sound quality.

    The only thing I've worried about in the past when I considered using the Peavey Classic 50/50 for bass that I originally bought my guitarist (bridgeable unlike your 60/60! WEIRD!) was that the power tubes were EL84's (if I remember correctly). So, don't people like the EL84's for their early breakup and crunch properties? That's why I never did try it out though I should have. The Peavey 120/120 that I'm considering is bridgeable though I have two cabs anyway. And though I don't know exactly what tubes are in them, they seem like the coke-bottle biggie types that I see in bass amps. I dunno. My knowledge in this area is lacking as well.

    Best of luck!

    -T
     
  4. kringle77

    kringle77 Supporting Member

    Jul 30, 2004
    Massena NY
    Yeah, I have tried this before at home but never on a gig because I like my live st up to be as simple as possible. This is a great idea. You get the "tube sound" but with a much better, tighter bottom end. I prefer tubes for top and mid sounds and solid state for lows. Even some small tube guitar combo amps on top of a bass amp sounds great.
     
  5. 6L6

    6L6

    Apr 7, 2005
    Hei !

    this amps are 6L6 equiped.
    They are clean in the sound,
    with a bit of warmth.
    put when they got pushed they have a nice
    "singing zone" where they get soft and sweet
    (listen to BB. kings guitar)
    My first real guitar amp was a
    fender twin reverb (4 x 6L&) and this amp sound's much
    like it. The peavey 120/120 also got 4 x 6L6 pr ch.
    (so it got 2 x fender T.Rev. :) )
    I have tried the amp in a high end HIFI.
    The mid bass and mid-range is surprisingly good !
    The low bass is also fine but, the high trebel
    could use a bit more gain.

    My long term plans are using a 3 amp. system
    one ch for 2 x 10" one ch. for the horn and
    another power full amp for the low bass.

    I am also wondering if i should use a Behringer digital
    crossover , but i am not starting a new thread for that :)

    The system don't have to be so large.
    I could use one 10" and a horn.
    And the PA amp could be a switch mode type.
    altsa the low bass cabinet could be smal if
    the PA amp is powerful.

    take a look at:

    http://www.harmony-central.com/Guitar/Data/Peavey/Classic_60_60-01.html
     
  6. Transverz

    Transverz believer of the Low End Theory

    May 3, 2004
    Los Angeles, CA
    So the Peavey Classics that we are looking at are 6L6 equipped, eh? Hmm. Okay, so that sounds good. What about the issue regarding their original intent (I believe) to have been guitar. Is there some sort of issue about getting "low" enough and recharge time and all that? I hardly know what I'm talking about, but basically, what consequences are there for these not being "made for bass" amps? Or is this not even an issue or concern because the sound is controlled really by the preamp?

    One more question: Think these Peavey Classic tube amps bare any similarity to the power section of other bass amp tube heads? What I mean is, are these amps truly viable replacements for a power section or are we just kinda "pushing" them to go in this direction and hope it works out? Sorry, I'm at my wits end right now trying to decide if I should make the jump and attempt to build this tube rig. Apologies.

    Thanks for all the help,

    -T
     
  7. The 0x

    The 0x

    Aug 24, 2003
    Timonium, MD
    I've done this with SS for lows & tube for mids & highs. Sounds really cool IMO.
     
  8. 6L6

    6L6

    Apr 7, 2005
    First of all i think that usally the kind of
    tube sound bass players are looking for are
    the power amp sound.
    The soft singing sweet spot.
    Just under the distortion zone.
    when the amp starts to compress.
    You can easy hear this sound at
    B.B. Kings solo's (Gibson ES-355 + fender twin reverb)
    listen to "the thrill is gone".
    He never overdrives the preamp but mainly the power amp.

    While overdriving a tube preamp gives you
    more a kind of crunsh or distortion.
    This is a nice sound too, but a different kind of sound.

    Over the years bass amps have been used by guitarists
    and also the other way around.
    How ever i think that guitar players can use
    bass preamps, i think the opposite is harder
    because of the missing EQ and compression.

    The deep bass performance of a tube poweramp
    is much influenced by it's output transformers.
    (Only ac voltage are able to go through trasformers.)
    So very low frequency does'nt go through.

    The 60/60 sound's good even at the low B.
    The amp sound's great with a bit of warmth
    (not overdriven)
    Tested with a single 15" and 2 x 10".
    When driven hard the 60/60 could have just a
    little more control with the 15", but still it's ok
    (the 120/120 is probably sufficient).

    The 120/120 in bridge mode should handle even large
    cone speakers i think.
    Or one ch. can take care of let's say a 15" and the other
    2 x 10" (electronic crossover is a huge advantage).
    So you might not need another SS amp.

    One very nice thing about the peavey is that you can vary
    the output impedance. mine has output for 4, 8 and 16 ohm.
    Running a tube amp in mismatch vill shorten the life on the tube's. (Changing 8 6l6 on the 120/120 is expensive.)

    If you buy this amp, it's importante that the tube's
    aren't old or of poor quality.
    If you already have a nice PA/SS amp the 60/60 might
    be enough to run a 2 x 10" for mid range.
     
  9. Rockbobmel

    Rockbobmel Supporting Member

    I tried this. It works. In fact, you can't tell that you even have a SS amp in the mix. It sounds all tube.!! You could use a small tube combo on top and a powered sub on the bottom. Nice.
     
  10. panazza

    panazza

    Nov 23, 2003
    italy
    hey... I tried something similar with my sansanp BDDI...

    ok, I admit the thing is a little different but...

    I just kept the eq pretty flat, with the blend knob set around 10 o'clock....

    this way the sound was more "SS" than"tube"....

    then I raised the drive and presence knobs, this way obtaining a very trebley overdriven tube sound.... mixing this sound with the "clean" sound using the blend knob, I managed to keep SS sound on the lows, while adding tube crunch on mids and higs.... very nice result.
     
  11. tombowlus

    tombowlus If it sounds good, it is good Gold Supporting Member

    Apr 3, 2003
    North central Ohio
    Editor-in-Chief, Bass Gear Magazine
    I am looking to move into this type of a rig as well. I currently have a couple of rigs in mind. For a "big rig" I would use my Aguilar DB 680/728 along with a Crest CA9 (probably driven by the low frequency output from the 680's crossover). For a "medium rig" I am thinking of using my (soon to arrive) DB 359 with an iAMP 800 (the two would fit nicely in a deep 4-space rack!). For a "small rig", I might try supplementing my Trace Elliot Twin Valve Combo with a Walter Woods and another 1x15.

    I have not tried this in a gig setting, either, but so far, I think that there is real merit to this approach.

    Tom.
     
  12. From my very limited experience with tubes, I think you are on the right track. Tubes definately give a more "alive" higher register sound (sweet to my ears), but the low end just doesn't have the tightness I'm looking for. the fullness yes, but the Tyson punch, no.
     
  13. Transverz

    Transverz believer of the Low End Theory

    May 3, 2004
    Los Angeles, CA
    Very encouraging. Darn you guys... can't you keep any money in my pockets?! Okay, I forgive you :D

    Darn. Just lost a bid for that high powered Peavey single spacer. That plus the tube amp would have made for a nice SS/T poweramp combo. I'll keep looking.

    Glad to hear other people's positive experiences. Especially that the Classic 60/60 is working out for you 6L6.

    Hmm. I do have a QSC RMX 850 and a Classic 50/50 (bridgeable to 100) sittin' around the rehearsal room. Of course the QSC will work out, but I almost know for sure the Classic 50/50 has EL84's in it (8 of them, I believe). That won't work out, will it?
     
  14. BB uses Gibson LAB amps and has for years. They're completely s/s, but have an excellent compressor for guitar application.

    Most decent output transformers are good to 10Hz, most are down only 3dB at 5 Hz. Low B of a five string is roughly 30 Hz. Even if you play on a hideously detuned multi-string beastie, you're not losing ANY fundamental tone to the output transformer. Only subsonic "beat/difference" frequencies get filtered, which helps tube amps be louder, since they're not wasting large amounts of power feeding their speakers frequencies that cannot be reproduced.