What's difference between guitar and bass speakers...Revisited-PJB

Discussion in 'Amps and Cabs [BG]' started by pixelpounder, Apr 3, 2019.

  1. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area
    Okay so I've seen the threads that explain that Bass speakers are inherently different in construction than Guitar speakers, so the possibility of having one cabinet to play through as a bass player / guitar player is impossible.... That was true for many years... until Phil Jones started producing both Bass and Guitar Combo Amps, with the same speakers.


    Today one can purchase a PhilJones C4 Lite cabinet rated at 400w and a PhilJones D-400 Compact Bass Amp Head and have a lightweight combination for bass.

    Or is it necessary to have a PJB amp with a PJB cabinet? Or could one just amp with something that has the potential to "do both" guitars and basses? Are we getting closer to a technology that just amplifies everything? Are we there yet? Thoughts?
     
  2. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    The main difference between guitar and bass drivers is that bass drivers have lower Fs and longer xmax.
    Understanding Loudspeaker Data | Eminence Speaker

    If you use the same drivers for guitar and bass there are going to be major compromises. One or the other can sound good through them, but not both. Up until the 1970s there were very few drivers that could be called bass specific, most were generic musical instrument drivers that had specs the same as modern guitar drivers. They sounded OK on bass, but they couldn't go very low because of the high Fs nor very loud because of the short xmax. Using a modern bass driver with guitar it won't have good highs due to the low Fs, and won't give an overdriven tone due to the long xmax.
     
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  3. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area

    So how does the Eminence Speaker data compare to what PhilJones has done? Are you saying that basically the PJB stuff is nerfed compared to larger bass specific drivers? Thanks
     
  4. Yosbank

    Yosbank

    Feb 6, 2019
    +1
    [​IMG]
     
  5. Fs and Xmax are important differences.

    Qts is typically lower for bass speakers (commonly 0.3-0.5). Qts for guitar speakers tends to run relatively high (0.6 - 1.5) so that the low end is reasonably full when used in an open back cab - the most common enclosure type for guitar speakers, or in sealed cabs (common to 412 cabs).

    Another significant difference is that (electric) guitar speakers are usually designed to contribute to the tone via substantial cone breakup.

    Along with this, electric guitar speakers are designed to have a more extended high end, typically 4-6 kHz. In order to accomplish this, voice coil mass is kept low by keeping the diameter in the 1-2 inch range, and coil length small (Xmax commonly 2 mm or less). These voice coil differences also result in lower thermal power handling - a 75-100w power rating is pretty healthy for a guitar speaker.
     
  6. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area

    Got it, thanks. All old school stuff. Question though: Is it possible to make one cabinet that can produce both a good guitar sound and a good bass sound. Can the new tech and little drivers that PJB uses do the job for both?
     
  7. It depends on your application: electric guitar or amplified acoustic guitar.

    The PJB's are more hifi than typical electric guitar speakers. They are well suited to amplified acoustic guitar.

    There are a few good guitar drivers that could produce decent bass to maybe 70 Hz at levels suitable for practice or small venue, acoustic gigs. You would have to tame the elevated highs with EQ.
     
    Last edited: Apr 3, 2019
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  8. fdeck

    fdeck Supporting Member Commercial User

    Mar 20, 2004
    Madison WI
    HPF Technology LLC
    In my view a full range speaker could work fine for guitar, but if you were counting on getting a particular tone quality, you might have to get it through some sort of effects or modeling. One of my band mates plays through such a system, with a Kemper box, and can dial in practically any conceivable tone quality at any volume.

    In my view, a speaker that works well for bass will involve some practical compromises when used with guitar, notably too big and expensive. If you want to play guitar, then take advantage of not having to haul a giant rig around.
     
  9. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    Bass drivers are designed to go a full octave lower than guitar drivers with high output in the lows, pretty much the exact opposite of guitar drivers. There's no new tech about the drivers that PJB uses. Also, bass cabinets are totally different from guitar cabinets, for the same reason that bass drivers are different from guitar drivers. They're no more interchangeable than bass and guitar strings.
     
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  10. What they all said, but I will add that my Genz-Benz NeoX2 2x12 cab sounds fantastic with Bass and Acoustic Guitar going through it, even at the same time.
    Bass into the front of the head as usual, Guitar through the mixer then into the head's power section. This was the only thing amplifying the instruments this day. Have done it a few times with others playing the Bass.
    It is fantastic.



    [​IMG]
     
  11. (electric bass amplification) Bass speakers tend to compliment the sound of electric bass.

    (electric guitar amplification) Guitar speakers tend to compliment the sound of electric guitar.

    Studio monitors / home stereo / upper shelf PA / f.o.h. systems tend to reproduce the whole enchilada.

    If good is good, then why aren't bassists and guitarists using PA cabs? Why aren't f.o.h. systems using bass or guitar cabs? Because they don't sound right.... try it, you will see. And, to quote a friend:

    "However, your results may differ. No warranty is offered. Please inspect prior to purchase. Dry clean only. Tumble dry on low setting. Check lug nut tightness after each 50 miles. Tire wear in excess of specification voids the non-existent warranty. Use DOT-3 brake fluid only. Inspect for water ingress."
     
  12. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area
    I was hoping that technology would save the day here, Sounds like I'll just grab a 2x12 guitar cab.
    Thanks, everyone for the wisdom.
     
  13. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    Unless you're playing 500 seat and larger rooms without PA support a 1x12 is sufficient. The #1 reason why bands play too freaking loud is guitar players using bigger rigs than they need, which they have to push much louder than they should in order to get the tone they want. #2 is they use cabs with more than one driver, which exacerbates high frequency beaming, which makes them turn up even more.
     
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  14. nilorius

    nilorius Inactive

    Oct 27, 2016
    Riga - Latvia
    Bass speakers are built to sing in lower freq. and they are biger and powerfull, guitars - higher freq. and smaller.
     
  15. johnpbass

    johnpbass

    Feb 18, 2008
    Glen Mills, PA
    The new Tech21 Power Engine Deuce Deluxe looks interesting for at least small to medium size gigs. I haven't seen any bass demos as of yet though, just electric and acoustic guitars.
     
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  16. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area
    Yea, and drummers with no volume control in smaller venues. Then the guitar players all
    That makes general sense but if you listen to this video you can hear that the PJB box with 5" drivers sound better than the others with large drivers. It appears that PJB has made that old argument go away.

     
  17. nilorius

    nilorius Inactive

    Oct 27, 2016
    Riga - Latvia
    What means better for you, means worse for others.
     
  18. pixelpounder

    pixelpounder

    Aug 26, 2006
    Chitown area
    Not sure I understand that response. It is clear from the video that the driver size issue is a non-issue for PJB boxes. The small drivers he uses "can easily" reproduce low bass notes.
     
  19. Rick James

    Rick James Inactive

    Feb 24, 2007
    New Jersey
    There's a basic flaw in that test. To be sure the difference heard they'd all have to be driven with the same amp without changing the settings. Besides, no one has said you can't use five inch drivers for bass. What determines how a driver works isn't the size, it's the T/S specs. Go back to Post #2. One of the constantly recurring questions here is about driver size versus response. The answer always given by those qualified to do so is that driver size does not determine frequency response.

    On the flip side is what would happen if any of those speakers were used with a '59 Paul through a cranked Marshall Plexi. None of them would give competition to a Greenback.
     
  20. lug

    lug Supporting Member

    Feb 11, 2005
    League City, Tx
    This is incorrect!!!

    (they are 4" speakers :D )
     
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