Low B - How to get it sound well
 

I own an Ampeg B2-RE with a GK 115BLX cabinet, and a combo GK Backline 112.

In both cases, my low B sounds horrible. Notes from E and higher sound very clear and well defined, but my low notes which I love so much are difficult to hear and not clear at all.

Any help on how to set my amp to fix this? Or what equipment I could get to get a really powerful and clear sound from the lowest notes

Kick down the bass, and bump up the lower mids. Or think about different cabs.

Most low B issues involve the bass, strings, technique and EQ issues, not the amp/cab in particular.

While most cabs cannot produce the Low B (and lower note) fundamental of 32hz or so, the primary 'meat' to the notes on the B string are the second harmonic, which even a little sealed 110 cab can reproduce.

EQ wise, the key is to NOT boost bass to try to force those deep fundamentals through a rig that can't reproduce them... you will just end up with mud and farting of the driver.

With the bass itself, a good setup will help, as will (especially on lower end basses without a lot of neck stiffness) a large gauge B string.

Finally, and often overlooked, is technique. Make sure that when you are playing your bass unplugged, you get the same basic response from the B string compared to the E string. Playing a B string cleanly can take quite a bit of practice and finesse.

So, the simple thing is to not overboost your bass control. The rest can take some time and experimentation. I often gigged back in the day with a little sealed 112 GK combo (the tiny little metal box model they still make). That combo rolled off at 100 hz, and the B string notes sounded great:). Not huge of course, but even with the E string.

Missing one important bit of info. What bass are you using? Also what type of strings?

As posted, most bass cabinets aren't made for fundamental notes of 32Hz and most ported cabinets will fart out or just not produce enough energy in that range to do any good. I posted some comments about the need for a sub-sonic filter in all bass amps and I stand by that. Also, as was posted, don't boost the bass- work with mid-bass and decrease the mid-range/treble and increase the volume/master/gain controls. The frequencies that we're most sensitive to, e.g., NOT bass, will mask the ones we're not sensitive to. If you cut the mids/treble, leave the bass alone and boost the volume, you have effectively boosted the bass, but you haven't reduced your headroom. Your frequency response curve won't indicate how you changed it, but it does show you that it was changed.

In order to get a clear sound from very low notes you need to look at both bass and amp/cab setup:

Amp: need to have lots of headroom. i.e. if you have thing thing set at 10, you're pushing too hard and will probably have significant distortion. Keep in mind that lower notes take more power to reproduce.

Cab: In order to reproduce low frequencies and still be loud, you need speakers with high excursion (termed, xmax). If your speakers have low xmax, you are at risk of cone over-excursion that will cause the dreaded "fart out". Unfortunately, most manufacturers do not give xmax as a specification but I would guess your cabs are in the 4-5mm range. A high-excursion woofer would be double.

Bass/strings: higher tension on your B string will help with definition. You can make some improvements with string gauge, but even better with a long "speaking length" of the B string (length from nut to bridge). This is why those Dingwall basses create such well-defined notes on the low B. The fan-fret design allows for the extended speaking length on the B.

+1 in general to your amp comment. Of course, at moderate volumes, you don't need a ton of power, so this all depends on how loud the player needs to get.

On high excursion, not as simple as you state it. Yes, if you want to get close to the fundamental of the lowest notes, a higher xmax will get those notes out there more loudly, if you have a single driver and all other things are equal. Multiple driver cabs with more standard drivers can actually result (IMO and IME) in a better B string response, if you are one who values the second harmonic, where most of the articulation and definition is.

Yes, most of what you hear in a B are in the harmonics BUT there is still energy (and thus cone excursion) being spent on the fundamental. Once you go into over excursion, you WILL distort. Some people solve this using high pass filtering. I guess we can add that to the list. Alternatively, a sealed cab doesn't really have to be concerned with unloading (but at the expense of SPL (volume)).

As I understand, you are referring to keeping xmax down by using more speakers? Sure, that can work too--but again, it comes back to excursion. As you know, low end SPL is all about surface area and cone excursion--no free lunch. You either need larger excursion or more surface area (more speakers). This is why a high excursion 15" can complete in low-end SPL with 6 "standard" excursion 10s.

Anyway, I think we are both just showing that there are many options to choose to improve the low end definition.

Most likely this is not an amp settings issue... :hmm:

Assuming you have a solid signal coming from the instrument, then it's likely a question of whether your cabs can handle that signal.

If not, then that leaves the instrument itself... :hmm:

MM

Check out this video!

http://www.youtube.com/watch?v=cLcwYNHDnPY

And try some lighter strings

+1 I'd put at at more like 2 x 12 or 4 x 10 for good quality drivers versus a 'PA subwoofer spec 15), and of course, the box needed to open up a speaker like a 3015LF is larger than most 212's and 410's. No free lunch in this business.

Almost certainly you can get a big improvement with EQing out the fundamentals and paying attention to KJung.

There are a lot of bass cabs that aren't very strong at 64hz relative to 82hz all the same. You can test this by playing sines from your computer.

The problem is compounded as the lower you go the worse you hear so even though the speakers may be doing ok it's not so impressive to the ears. Be careful with the sines.

To be perfectly honest, I rarely play on open "B". I use that string to play lines without having to adjust my left hand.

Me, either. The low B isn't the reason I have a B string.

+1... However, same issue all the way down from the E regarding gear, and same technique issue across the length of the sting.

What makes a low B sound good?

1 - A good setup flatten out the neck and get the action low enough and check the nut height.
2 - Good strings.
3 - Good EQ. 2 band preamps and scooped out eq's are not your friend here. You need to boost mids to get a good low B tone.
4 - Good amp.

I agree with every points here except one: nº3

Actually a well centered low eq enhance a lot the B string response if you use it judiciously. Example: Sadowsky pre, Glockenklang pre are one of the pre I tried and really helps the B string.

Boosting anything below 64hz is counterproductive.

Thanks for the help guys.

Regarding the question of what bass I'm using, it's an Ibanez BTB 556MP.

The strings are quite old (I think) cause I bought this bass very recently, 2nd hand, so I have no idea how long they've been there, but I'll be changing them as soon as I find the time to buy strings. I'm going for Elixir strings, but I'm not sure what gauge yet. Any recommendations?

Also some mentioned words which are new to me...what do these mean in the context of bass guitars & amps:
xmax
excursion
second harmonic
fundamental
sealed cabinet/non-sealed cabinet...what's the difference?

Thanks loads! xD

There is a little trick to get a bit more definition from a B string. Press down on the string with your thumb, just immediately in front of the bridge saddle. This creates a sharper witness point over the saddle, resulting in a better focus. It's surprising how many 5 string basses I see where the string comes over the saddle in a big arc, rather than a nice, defined bend.