Do you get more volume per watt with tubes vs SS

Discussion in 'Amps and Cabs [BG]' started by pgurns, Sep 18, 2005.

  1. pgurns


    Dec 26, 2003
    Northern, IL
    I'm sure this can be greatly subjective and will differ from brand to brand. but, generally speaking, all other things being equal (same cab, bass etc) will you "usually" get more volume per rated watt with tubes in the power section vs all solid state or hybrids?

    The reason I ask is that I'm looking for a new head or pre/power setup, and it appears that a lot of all tube heads are rated at lower wattage than hybrids or all solid state units. Can you get the same volume from 200 watts - all tube as you can from say 400 wattas SS? I am particularly interested in the Traynor YBA-200 but I wonder if it will have the power I want. I used to own a GK 400rb and a SVT 3 PRO. both run through an Avatar B212 cab (4 ohms). Any idea how it might compare?

    Thanks in advance for any input
  2. TheChariot


    Jul 6, 2004
    Boston, MA
    Let me save you before you get mauled by angry gear-heads.

    Technically.... a 300Watts of SS and 300Watts of Tube put out the same amount of volume... according to an SPL meter. However, the human ear PRECEIVES Tube watts to be louder, which I believe is due to the harmonics of tube output.

    So... to be politically correct, tube watts SOUND 3-4X louder than Solidstate watts.

    So as an example, an Ampeg SVT-CL will sound about as loud as an Ampeg SVT4-Pro.

    And in your situation.... the YBA200 will sound like approx 600Watts solidstate, and will be louder then the 3Pro for sure. Hard to believe because its so cheap... but its a great deal, especially after changing the stock tubes.
  3. pgurns


    Dec 26, 2003
    Northern, IL
    Thanks for the speddy reply. I did a search and did not really come up with much as far as this goes, then again I may not have hit the right keywords in the search. I did a search for the yba200 and it seems to get glowing reviews, I just want to make sure it is powerful enough. I have read that tone comes from the pre and not the power amp section so I am still trying to figure the whole deal out LOL.
  4. Plain Old Me

    Plain Old Me

    Dec 14, 2004
    I'd say more tone in a tube amp comes from the power section, though the pre is important too. In most all tube amps the pre has more tubes than a hybrid as well. Besides that, you can't get power tube overdrive from a preamp tube.
  5. Tash


    Feb 13, 2005
    Bel Air Maryland
    The perception of tube watts being louder ahs more to do with the way tubes attenuate as they are pushed. Simply put tubes pushed to 100% or more of their "on paper" capacity sound as good or better than tubes pushed to only a fraction of that. While transitors begin to clip and sound "bad" at only a fraction of their rated output.

    So while a 300 watt tube amp and a 300 watt SS amp are both 300 watts, the 300 watt tube amp is 300 useable watts, while the 300 watt SS amp can probably only deliver 1/2-2/3 of that an still sound good.
  6. Arthur U. Poon

    Arthur U. Poon

    Jan 30, 2004
    SLC, Utah -USA-
    Endorsing Artist: Mike Lull Custom Basses
    I've also read this same statement here many times and I've had the local guys who use all-tube bass heads tell me this also. Of the few all-tube heads I've owned (SVT-CL & SVT 2-Pro) they got plenty loud when you cranked them up, but for some reason, at high volume levels the distortion they produced was too much distortion for my taste. YMMV.

    However, IMO the original SVT head from the late 60's/early 70's that I used to borrow from a friend could get insanely loud, with a more subtle distortion that was the sweetest sounding bass tone I've ever heard. When I think 'harmonic tube distortion' I always think of that old SVT. (I want one really, really bad!)

    I don't have any experience with the YBA200, so I can't offer a comment on it.

    I've owned an SVT 4-Pro and I agree with this 100%. I tried it in bridge mono mode through a 4 ohm SWR Goliath SR 6-10" cab and it's 1200 watts didn't even compare to either of my all tube SVT's cranked from a volume or tone standpoint. Although I do think it's tone is a very good one.

  7. Plain Old Me

    Plain Old Me

    Dec 14, 2004
    +1 on the old SVTs. The new ones give a good impression, but nothing beats the origional!
  8. el_Kabong


    Jul 11, 2005
    I keep reading this, any tube amp gurus here to tell us in hard technical terms why this is the case? Hello PBG are you there?

    edit: oops sorry, didn't mean to hijack!
  9. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Tubes when pushed compress the signal, much like a 'soft knee' setting on a compressor. As a metaphor imagine running full speed into a wall padded with six feet of foam rubber. That's what happens when a tube is pushed hard. The signal is gently 'squished' and eases into clipping, and starts doing so at a fairly low level, which the ear interprets as 'warmth'. The change between pristine clean and fully distorted is so gradual that it's not obvious. SS amps tend to run very clean to their output limit and then go right into a hard clip. Imagine now running full tilt into a brick wall. Because the transition from clean to distorted is so much more obvious with SS one can't run as close to the amp's limit and still have it sound good. Beyond that, the type of distortion created by tubes is pleasing to the ear, so one is not going to immediately back off the volume when it occurs, while the distortion created by SS sounds nasty and is much more obvious when it is present.
  10. jz0h4d


    Apr 26, 2005
    Here's a real world example. I was at a jam about a year ago where there were two bassists. I was using a SWR wm12 12' speaker w/120 watts, he was using a ampeg (tube) b-15, 15' (JBL) speaker w/40 watts .
    The B-15 ruled, it was louder than my WM12. It was quite distorted but it didn't sound bad. It put the WM12 with 3 times as much power to shame.

    Tubes sound louder because you can tolerate the mostly 2nd harmonic distortion.

    P.S. I know you can measure it on a SPL meter.
  11. el_Kabong


    Jul 11, 2005
    No Bill I was completely off topic, I meant why do the old ampeg tube heads supposedly sound superior to the new ones. But I'm probably pushing my luck asking again so I won't. ;)
  12. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    A lot of stuff mentioned above lies somewhere between urban legend and total BS!!!

    1. A watt is a watt. Speakers do not care about tubes vs. transistors.

    2. The idea of tubes clipping and compressing gracefully is nice on paper, but only matters when the amp is driven into clipping! If the overall volume is low enough so the amp never has to put out it's maximum, then this is a moot point.

    3. 3-4X louder to your ears is a ludicrous claim. To be 4x as loud you need 100 times the wattage! That would a mean a 4 watt tube amp would sound as loud as a 400 watt solid state amp...I don't think so!

    What IS true:

    Loudness as perceived by our ears is due to many things. Just having more midrange content makes something sound louder even if the actual SPL is no greater.

    There are some psychoacoustical phenomena regarding distortion artifacts that can make tube amps sound louder. There is an engineering paper from the early 70s that has been posted on the net and is often quoted that discusses this.

    If you need more volume just crank up the midrange in your sound and add some more/larger speakers to get higher acoustical efficiency.
  13. MrBonex


    Jan 2, 2004
    New Hampshire
    OK. Please forgive me, cause I read this YEARS ago. Last century, at least. Some of the facts may be a little skewed, but the gist (I think) is OK.

    John Meyer, of Meyer Sound fame, was asked to develop the sound system for the Apocolypse Now movie. The standard for the time was the "Earthquake" system developed for the movie of the same name, but designed many years before.

    John built this hugely powerful and hugely huge system and installed it side-by-side with an Earthquake system. The EQ system was much, much smaller and much lower powered. By all standards of measurement, the JM system should have blown the EQ system out of the water. But when they tested them, the EQ system seemed much louder. It was a classic *** situation.

    It turns out that the reason the EQ system sounded louder was DISTORTION. The distortion was not percieved as distortion, it was percieved as VOLUME! Apparently, it's not until distortion reaches a very large percentage of the total output is it percieved as annoying distortion. When John purposefully added distortion to his system, it seemed louder.

    SO. What he (and we) learned is that distortion (up to a point) is heard as loudness by the human ear. Now to the point of this thread. Tube amps go into distortion in a way that is more mellifluous to the listener. We don't hear it as distortion per se, we hear it as louder. Because S.S. amps tend to create a more annoying distortion (harsher), the line between the perception of loudness and annoyance happens sooner.

    Hence, tube amps seem louder per watt.
  14. AGCurry


    Jun 29, 2005
    Kansas City
    +1. Thanks for responding to all the misinformation, so I didn't have to.
  15. popinfresh


    Dec 23, 2004
    Melbourne, Aus
    Yeah yeah, I know. Pretty much everything on this matter has being said. But I would just say that my 400 watt all tube V8 is louder than ANY SS head or amp I have ever used, even before it gets 'dirty'.
    I know a watt is a watt etc etc. I know all the facts. But I also know that what I have sitting next to me is the dang loudest thing i've ever put a bass through.
  16. Lyle Caldwell

    Lyle Caldwell

    Sep 7, 2004
    The ear does perceive distortion as louder. That's a big part of it.

    The other issue is how amps are measured and rated. If the amp is measured and the measurement is taken at the onset of distortion, then you get very different results with a tube amp vs a solid state.

    When a tube amp is at the onset of distortion, there's still more volume to be had from the amp, and the ear doesn't hear the onset of tube distortion as distortion. So it will still sound clean quite a bit above the level where distortion is measured. In this instance, a tube amp that measures 200W at the onset of distortion may give 250W before that distortion is heard (these numbers are arbitrary and non-scientific, but good enough for the point).

    When a solid state amp is at the onset of distortion, it's about maxed out. Any further level will result in very apparent distortion, which will sound unpleasing. So if a solid state amp measures 200W at the onset of distortion, you're pretty much only going to get 200 usable W from it.

    That does not mean that a 200W tube amp is louder than a 200W solid state amp. That means that the measurements used don't tell everything the user needs to know. The wattage rating is not the only variable you have to take into consideration.

  17. From my experience, how amps behave at their performance limits is a leading factor in the subjective quality of an amp. Any decently designed power amp should be pretty close to transparent when it's well within its linear range. Differences between power amps become apparent when you approach clipping.

    Part of the 'tube sound' comes from how tube amps behave when pushed. The 'soft clipping' behaviour manifests itself in being able to run a tube amp further into clipping before the distortion becomes identifiable as distortion in the traditional sense. In a class AB power amp (like most big tube amps) I think that the primary differences can be attributed to less global negative feedback than in a solid-state amp and to the output transformer. The whole even-order harmonics thing is not really applicable. All class AB amps suppress the 2nd harmonic by phase cancellation. Now class A will give you lots of 2nd order distortion....But it will with tubes or transistors...
  18. jz0h4d


    Apr 26, 2005
    Since you know everything Brian why was the 40 watt B-15 louder than the 120 watt SWR wm12?
  19. Chasarms

    Chasarms Casual Observer

    May 24, 2001
    Bettendorf, IA USA

    Could be several things and is likely some combination thereof:

    1. 15" v. 12" driver
    2. general efficiency of the speakers
    3. Design of the enclosures including airspace and porting
    4. input signal
    5. Equalization

    There's five. There are at least 20 more that you could talk about.
  20. pgurns


    Dec 26, 2003
    Northern, IL
    Thanks for all the replies. I can see that there is no real answer here. I understand the scientific explanation of a watt being a watt, but the popular concensus from real people in the real world seem to indicate a tube amp being percieved as louder (all other things being equal). Perhaps the biggest reason is the one Lyle pointed out....we may be comparing apples to oranges in that the way one maufacturer derives the ratings may not be the same method as another ones does.