Huh!?! are they nuts?!?

Discussion in 'Amps and Cabs [BG]' started by SRSiegel, Nov 28, 2001.

  1. SRSiegel

    SRSiegel Guest

    Sep 17, 2001
    Ann Arbor, Michigan
    Ive been looking for a cab that handles the B string well. many have pointed me to the Peavey 412TVX, and i may go that way when i get the cash. But i found this:

    the specs give the box tuning frequency at 50 Hz. doest this mean that it would be dangerous to feed any note below 50 Hz into this cab? hence, even low E could unload the speakers? Bgavin? Joris? Opinions? Peavey doesnt state the tuning frequency on their website. The 50 Hz thing has me a little paranoid. It would make sense for 30 Hz, but 50!?

    One other thing. on the peavey website, they give 450 watts as the continuous RMS, and 900 as the program handling. then if you go to their "compare cabinets" spreadsheet, its listed as 600 watts RMS and 1200 peak. so which is it? or am i just not up on all the terms?

  2. Every speaker manufacturer around will tell you "do not use the cabinet below the tuning frequency." It's in print, and it's been proven in the lab. The drivers unload at a 24 to 36 dB per octave slope below the tuning frequency. This is the same as running your drivers in open air.

    Can you do it? Yes
    Is it the right thing to do? No

    I'd pass on the Peavey if you are a 5 string player. Or a 4 string player.
  3. Matthias


    May 30, 2000
    Vienna, Austria
    I have noticed a certain 'tuning hype' here on TB recently.
    I don't care too much about this - theory is one thing, practice another.
    (E.g. I've been using a home-made cab which is tuned at around 80Hz for years now without any problem, and yes I do play a 5-stringer)

    Either you like the sound of a cab or not.
    I guess they would not sell a cab which will puke speaker cones as soon you hit the low B.

    However I did not like the Peavey 412 at all. It is very loud, yes, but it lacks some ... bottom, which I would expect from a cab of this weight and size...

  4. SRSiegel

    SRSiegel Guest

    Sep 17, 2001
    Ann Arbor, Michigan
    thanks for the replies guys. yeah the 50 Hz this has me wary, ill probably pass, although i do have a get feeling that it may be incorrect, because well.. thats just idiotic. like bgavin said, thats not even properly tuned for a 4 string player. of course peavey gear cant be mail ordered anyways, so id have to try it out. i think ill try and contact peavey if i can. anyone know a good way to do so?
  5. I'm happy you have discovered an acoustic secret about how to use a cab at 80Hz with your bass. That secret has eluded the best minds and JBL, ElectroVoice, Altec, and the others for more than 50 years. You are welcome to believe anything you want, and discredit all those engineers as 'hype' if you choose. Religion has always been based on faith. However, facts vs beliefs are often times quite different.

    From the ElectroVoice 15BX datasheet:

    Generally, bass-guitar system performance is improved if the enclosure is vented or tuned for roughly the lowest notes that will be played through it. For standard tuning four-string bass, a 44 Hz tuning is recommended. The low "E" on a bass guitar actually vibrates at 41.2 Hz, but a 44 Hz tuning will provide a reasonable amount of vent contribution or additional output at 41.2 Hz. Similarly, an enclosure tuning of 34 Hz is recommended for a system that will reproduce standard five- or six-string signals. If a four-string bass with a "dropped-D" is used, the recommended tuning frequency is 40 Hz.

    From the JBL Enclosure Guide:

    Do Not Expect 20 Hz From a 40 Hz Box. Bass-reflex systems should not be operated below their tuned frequency. If you try to operate the cabinet below the tuned frequency, you will break woofers. Do not try to reproduce alpha waves or lunar cycles with a speaker not designed for that purpose.


    Gee folks, that second quote is just about as simple and direct as it can possibly be: "you will break woofers."

    Why not call Peavey and ask them why? Maybe it's a typo or maybe it's just a crappy design.
  6. SRSiegel

    SRSiegel Guest

    Sep 17, 2001
    Ann Arbor, Michigan
    i don't know about the rest of us, but i am quite willing to say that i know close to nothing about speaker cabinets. and what i have learned, i owe to the guys on talkbass here. (esp. bgavin and Joris) i appreciate your help. i will try and call peavey as soon as i can find a phone number for someone to contact, and some spare time to sit down and do it. damn college...
  7. BigBohn


    Sep 29, 2001
    WPB, Florida
    I'm not sure about the Peavey, but the Eden D-410XLT, a popular among alot of 5-stringers, has a frequency range of 2dB with 50Hz to 13KhZ. The B string on it is very well defined to hearing, and the B can be felt, as well.
  8. Slater

    Slater Leave that thing alone.

    Apr 17, 2000
    The Great Lakes State
    Peavey does a decent job answering questions on their website Forums.
  9. Davemell0


    Nov 19, 2001
    SW Virginia
    ok, my humble opinion on the whole thing. you can have a cabinet that has a really good sound and is tuned to a higher frequency, its just not going to be helping the speakers produce any more bass than they would in a free air system, this is fine for playing quietly (relatively quietly anyway) but if you want people's chests to be rattling 30 feet away when you hit your low B, you need a speaker cabinet that has a flat response curve down into the 30hz range. However as other posters have said, I'd be dissappointed if I had to carry such a big cabinet around and it didn't put out some kickin bass.
  10. 50 Hz is pretty low. The fundamental frequency of the string is only a few percent of the total sound (See thread "tech junkies gather round"). You'd be surprised at how clean and b*tt shaking a low B can sound on a cab with a 50 Hz tuning. I have a 2x8 cab which is tuned to 70 Hz. It completely rocks, down to low D. low D is 36 Hz. But this 36 Hz is only a few percent of the signal. The first harmonic, 72 Hz, that's where your bottom is. It's 5 times stronger than the fundamental.

    Don't let specs get in the way of choosing a cabinet. You're not gonna know how a cab sound if you don't LISTEN to it.
  11. SRSiegel

    SRSiegel Guest

    Sep 17, 2001
    Ann Arbor, Michigan
    alright, thanks for the info. what i am the most concerned about is wether or not the cabinet would be able to take the abuse a low B string throws at it. the 50 Hz tunign frequency made me worry that playing a lower note through them at any volume would blow the woofers.
  12. Matthias


    May 30, 2000
    Vienna, Austria
    There is no secret.
    It is a 12" PA-woofer (Celestion K12-200e) in a small ported box.
    All I know is: when I plug in my bass (and amp of cause) it works. It makes a sound that sounds very much like my bass without breaking cones at a volume level more than sufficient for my needs.
    FYI the speaker is rated 200W/8Ohm and I use amps which are rated 125W resp. 75W @ 8Ohms.
    This is not a question of 'believe'.
    This cab is working for 9 years and 8 months now without a problem - that's a fact, believe it or not...

    Also I did not mean to discredit any engineers.
    All I wanted to say is, that it is simply not true that you can not use a cab which is tuned higher than 40Hz or so. And that you should rather listen to the cab than study it's specsheets.

    And no, I do not want to discredit specsheets here.:D
    You need specs of a woofer when you want to design a cab for sure. But as pointed out in numerous discussions here on TB, CAB specs provided by the manufactureres are questionable in many cases and not really comparable, because we don't know how they are derived.

    I remember someone saying: All the specs I care for are impedance and weight. I like that. :)

    Finally I did not mean to insult you.
    I know that you work a lot with and on specs of drivers and cabs, design your own cabs and all that.

    But I consider it unfair, to tell someone not to buy a certain cab, only because it is rated at 50Hz and not 44Hz or lower.

  13. Bruce Lindfield

    Bruce Lindfield Unprofessional TalkBass Contributor Gold Supporting Member In Memoriam

    I agree with that entirely - just listen to it! I have found over 20 years that specs just bear no relation to how the thing sounds and one cab can sound exactly how you want but have the same basic specs as another cab that sounds horrible!!
  14. I think the original question should be read once more: he wants something that handles the B string well. He also mentions 450 watts RMS input power. What is apparently not being considered here, is the intended use of the cabinet. He is considering a 4x12 here... this is a lot more than something he is going to run in his living room. The question is about suitability to a task, and not about "tone".

    As for your cab working, I fully expect your 12" small box to work, and I also don't expect it to hold up under high power and low notes. But then I have a feeling you don't really push it very hard, as it has lasted 9 years and 8 months. If you never push hard enough to exceed Xmax, you'll never blow it up no matter where it is tuned. As for being tuned at 80 Hz, and being in a small box, it must have a substantial boom in the midbass, but this is a preference issue, and not a suitability issue.

    For example, I run my Peavey Minx 110 with my RB5 on the open B all the time, and it sure isn't tuned at 31 Hz. Does it work? Of course it works. And it reproduces the harmonics of my low B, but not the fundamental. The fundamental is there alright, but isn't reproduced well. And if I could drive it with more than 30 watts, I'd blow it up on Low B due to excessive cone movement from lack of damping at 31 Hz.

    We can all find examples of things that work outside the design specs. You can tach your car into the redline. It will probably work, and maybe even for 9 years and 8 months. But you will eventually destroy the engine by being bull headed and operating it outside its design limits. You can overclock your computer, if you can keep the heat under control, but you still burn it up prematurely. And we all know those guitar players who overdrive the crap out of their tube amps in the name of "tone", and then have to retube frequently.

    C'mon guys... this is looking like you can't see the forest for the trees here. :D

    I'm not so much insulted as I'm amazed at how "just listen to it" (read: faith) is used to justify operating a piece of equipment beyond its design parameters. Those of you who are builders certainly understand cone unloading and the rapid increase in excursion below Fob. Operating below Fob with high power blows drivers. JBL knows this and so does E-V.

    As to unfair? I don't think so. Fairness never enters into this. My statement above was "I'd pass", and I would still pass. IMO, this 4x12 is going to driven loud and low, and is not suitable for that purpose. Tone never enters into it. There are better choices than this Peavey for his purpose.
  15. Matthias


    May 30, 2000
    Vienna, Austria

    He also asked if "it would be dangerous to feed any note below 50 Hz into this cab".
    I don't use my 112 in my living room either.
    He did not mention what will be the task of this cab (not the living room, agreed ;)) but the first question about handling the low B well has got something to do with tone IMHO.

    Sometimes I ran the amp close to clipping, but as I said, the power rating of the cab is quite a bit a higher than the rating of the amp.
    The cab has midbass boom indeed - but this is not too bad in a live situation...


    So you believe that this cab is designed for 3-stringers (A-D-G) or what?
    Maybe Peavey should attach some warning sign...
    I see things different here.
    He will have to see if the cab plays loud and low enough for his needs. And if he likes what he hears, he should not stay away form buying only because of the tuning frequency.
    I still don't believe that this cab will break, when used with a 500W amp (without clipping) and a 5-stringer.
    Agreed :D

  16. I think this whole dialog has become pointless. It is useless to argue points back and forth because I see no merit in your points, and you see no merit in mine. We can agree to disagree.

    As I stated earlier, he should contact Peavey and ask them. The 50 Hz thing might be a typo made by the person creating the ad copy. Wouldn't that be a joke?
  17. Matthias


    May 30, 2000
    Vienna, Austria
  18. CrawlingEye

    CrawlingEye Member

    Mar 20, 2001
    Easton, Pennsylvania

    I know that it's incorrect.

    "Frequency response: 30Hz to 15kHz"
  19. From what I can tell, the discussion is about box tuning frequency, not about frequency response. Although I couldn't find the spec sheets online at the Peavy site for the TVX cabs, the 115 BX BW spec sheet shows a 30hz frequency response and 40hz box tuning frequency.
  20. SRSiegel

    SRSiegel Guest

    Sep 17, 2001
    Ann Arbor, Michigan
    well guys, heres the verdict. The ad is correct. I emailed the customer service guy at peavey (Roger) and he replied:

    "Hello Scott,

    The box tuning frequency of the 412 TVX is 50 Hz. This is just the box tuning,
    and has little bearing on the low end frequency cutoff.
    The low end cutoff is 30 Hz. this rating is the -3 dB downpoint. All Peavey
    frequency response specs are given at the - 3 dB point.

    Let us know if we can assist further."

    So it looks as if the frequency response curve is accurate, and quite impressive, also given that the cab is rated at 100 Db SPL. i may be wrong though. I sent a reply asking "wouldnt the high tuning frequency cause the drivers to unload below 50 Hz, and hence possibly cause mechanical damage at any frequency below 50 Hz?" I will post Peavey's reply when i get it.

    However, Peavey is a well reputed company and known for their durability. Is there somethign I am missing here? Is there some secret that makes the Sheffield drivers invinceable? hopefully I'll find out. when i do, ill be sure to let you know. thanks for the replies.