I think I screwed up!

Discussion in 'Amps and Cabs [BG]' started by pom134, May 20, 2007.

  1. pom134


    Apr 2, 2007
    So I know have an Ampeg B4R, a Bag End Q10BX-D and an S18E-D. I'm picking up the 18 Hz Integrator soon, but now that I think about it I think I really screwed up.

    The amp is running in mono bridged mode so there is only one output. From what I understand, I run the integrator before the amp and the processed signal goes to the amp and is amplified and BAM huge low end. The problem is only one of my cabinets is able to take the super low frequencies!

    So is there anything i can do to run both cabs effectively with the integrator? I was thinking of putting a high-pass filter on the 4x10 but I don't know if that will effect the signal going to the 18!

    my buddy is an electrical engineer, he said i should put an inductor of the right H in parallel after the 18 but before the 4x10 and it should act as a high-pass. As I understand it, usually capacitors in series are used for highpass, but he said in my case it would make more sense to get an inductor in parallel

  2. Hum it probalby won't help you but...

    If you really dislike the sound of your amp that much, why go through so much hassle, and put inductors capacitors in order to get more low end. Just sell your head and buy a new one that suits your needs better. You do realize that everytime you heard a really good bass sound live or recorded it was through stock equipement. Do whatever you want to do. but in all honestly I think you are taking the worst possible route in getting a sound you like. Experience told me that if you don't like a bass, head or cab no mods you'll ever do to them is going to make you like them. There are thousands of amp brands out there with teams of proffessionals paid to design amps, Don't forget that.
  3. 4Mal

    4Mal Supporting Member

    Jun 2, 2002
    Columbia River Gorge
    Best way I see out of your scenario is to add a power amp and take a line off the Ampeg to drive the integrator then the amp. You could nail down a QSC PLX2402 at 400 to 450 in the used market - problem solved ...
  4. pom134


    Apr 2, 2007
    Well all im saying is, the INFRA thing boosts the signal at lower frequencies and that boost is getting sent to BOTH cabinets. The problem is the 4x10 is not designed to play down to 18 hz or whatever.

    first of all I havent heard it all together yet, the amp and 4x10 are up at school. so if i throw the highpass in front of the 4x10 then it should counter act that boost and i should be getting what i was getting before with no processer. im not modifying any equipment im just blocking some low end coming from the amp.

    now this is all assuming that the 4x10 wont like taking anything under its posted 40 hz. but a low B is around 30 hz and im sure people use 5 strings with these things so im not convinced it will be that bad. i play in c# sometimes with a metal band and thats 36 hz so its not like im going to be pushing 18 hz.
  5. Daytona955i


    Feb 17, 2005
    Albany, NY
    Why don't you just use the biamp feature in the head?
  6. pom134


    Apr 2, 2007
    cuz thats only 200 watts per channel then. not enough power for either cab.
  7. pom134


    Apr 2, 2007
    how does that crown work? I could use the XLS 202 to get 600 watts to the 18 and have the integrator.
  8. I've got the same (except for a B5R) rig as you. You really need to run you system bi-amped (another amp) to make this system work. The integrator adds a specific slope equivalent to the roll off of the Infra cab on the low pass output to acheive a flat response out to 18hz or 8hz depending on you're itegrator and it's settings. The high pass output doesn't have this slope and has a fairly high pass frequncy removing a lot of lows out of the 4x10 cab. I believe this is adjustable by either moving some resistors inside the integrator or front panel adjustments depending on you're integrator. I currently run the pre-amp out of the ampeg into the integrator, low out to an external amp and high out looped back into the power amp in on the ampeg. It works but I'm going to go to bigger amps for both cabs before too much longer.
  9. pom134


    Apr 2, 2007
    ok i got it all figured out.

    Bass > INFRA

    INFRA low > QSC XLS202 > S18E-D
    INFRA high > B4R > Q10BX-D

    but does the infra have a highpass that will make my q10bx-d not play and lows???
  10. pom134


    Apr 2, 2007
    ooo yea tahts better so

    Bass > B4R > Q10BX-D

    B4R line out > INFRA > INFRA low > QSC XLS202 > S18E-D
  11. Quite frankly, why do you need to go down to 18 Hz? The human ear cannot even hear that frequency! I play a 5-string, and when I record most of my sound is really in the 100 Hz and up range. Sure, I get some 32 Hz fundamental of the low B, but when its cut you can barely hear the difference. While you can do it the way you have it (instrument-->signal splitter-->Ampeg head and Infra+power amp-->cabs) I dont see any reason to do it.
  12. pom134


    Apr 2, 2007
    beacuse the 18 has alot of roll off below like 50 hz (I think). honestly im going to actually listen to it before i decide.
  13. Hi.

    Just to cover my behind ;) .You might not want to do this experiment unless both Your amp and Your speakers are of quite good quality. A creased cone is just a few seconds away.

    :) If You haven't done it already, input these frequencies:


    To the WinISD signal generator, or something similar. Then CAREFULLY fiddle with the low frequencies and the volume pot/slider whatever, to get the sound out from Your speakers.

    When You see the cone flapping like bat wings in a Ozzy show, back off the volume a little.

    These are obviously only the fundamentals, but gives You an idea.

    As You are reading that link, pay attention to the low end wavelenghts also, something to consider ;) .

    Just my 0.02€
  14. greenboy


    Dec 18, 2000
    remote mountain cabin Montana
    greenboy designs: fEARful, bassic, dually, crazy88 etc
    People and installations using INFRA/whatevertheoldnamewas processors and INFRA-designed cabs don't necessarily need to go to 18 Hz, but because INFRA can go down to 18 Hz, it also can deal with say 30.87 Hz fundamentals without the huge rolloff conventional cabs and processing are capable of.
  15. greenboy


    Dec 18, 2000
    remote mountain cabin Montana
    greenboy designs: fEARful, bassic, dually, crazy88 etc
    There is a physical cost for using INFRA/ELF principles however. At 24 dB per octave boost below I think it's 80 Hz, and the thermal and excursion limitations of the cabs, if you plan on having a lot of SPL, the lower you go, the more cabs and amps you need. Again, no free lunch. However, a lot of Infra use in bass rigs has not been to have equal SPL at the lowest desired frequency, but just to have some SPL down there, making the general spectrum more obvious and pleasing.
  16. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis

    You are gonna use up all your power on those lows, and nothing left for tone and projection, IMO....

    B) the parallel inductor is a particularly bad idea, as it becomes a short at low frequencies. Tell him "the source impedance is well under 0.1 ohm" and he should get it. Never mind what that means, he'll know.

    C) The bag end stuff can sound pretty nice, but it DOES suck up power, AND it really pushes the motion limits of the speakers, as well as the thermal limits. I have heard systems at the NAMM show that sounded great, right up the the point where you suddenly heard an obnoxious "BLAAAAT" noise. Not sure if it was clipping or motion limits, bit it clearly was over the "TOF".
  17. Geddyfleaharris

    Geddyfleaharris Supporting Member

    This thread is way too complex for me. I have not yet attained my degree in electronic engineering. If I have to think this much to play bass then I am ****ed! LOL

    Not flaming or disrespecting.

Share This Page