need some help from the bass players

I dont personally play much bass, but my dad does in a band.

I'd make sure it's flat to at least the lowest string on a 5 string which if I remember correctly is 31hz

High frequency extension is also vital due to the many harmonics produced by string plucking(slapping picking or whatever style you choose to play). I dont know a specific cutoff there, but I'm sure 10k is more than adequate and you can probably get away with Alot less.
 
If the bass is a 4 string, then you can make it flat to ~40 Hz.
I would use a large ported enclosure with a nice Pro woofer or a coaxial. You need to be flat to 40 Hz if you plan to play outdoors or in very large rooms. If it's for a small room, you could use a shallow rolloff from 200 Hz to about -6 dB at 40 Hz I guess.
 
xstephanx said:
but if the lowest fundamental is 31hz i might be in some trouble, there arent a lot of woofers that will play up to 3khz and drop down to 30hz. within my price range that is.

Well, you haven't said what your price range is, but I find that statement hard to believe. For budget applications, you can just use a PA speaker instead of a proper bass speaker, and PA speakers are available very cheaply, there are many cheap 15" PA speakers out there. Personally, I would prefer a smaller brand name bass speaker to a bigger no-name PA speaker, but that's just my opinion.
 
Pro drivers are probably the way to go.

If you have alot of money to spend on it, and I'm guessing you dont because you said it was a tight budge, you could use a few extremis midwoofers from adire. I think those would be killer for a bass amp. 30hz-5khz but at $100 apeice and 86db efficiency they might not be the best option.
 
xstephanx said:
Im going to chase my 11 year old dream and finally get a bass. I decided to build my own amp. Im fine with modelling stuff, i just need to know certain things

How low should a bass amp be able to play? (eg"it should be able to play -6db at 40hz")

will two 15s each getting 100 watts do the trick?

thanks all!

Is this going to be for practice, or do you plan to do some shows right out of the blocks? If for practice, then there is no reason for large dual-15" cabs man, not even close.

If I may make a suggestion, while you are learning, and getting started, go with the KISS approach here. Build yourself a cabinet for the Eminence Legend B102 10" Bass Guitar driver and have at it. This driver is an excellent learner/practive driver and covers the top end well enough to where you don't really need the tweet.

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=290-495&ctab=2#Tabs

If, after you learn to play really well, or at least well enough to warrant building anything bigger, then by all means, go bigger and badder.

What amp/head are you panning on using for said learning/practice set-up?

Noidster
 
hi .. i m playin bass and i m tryin to build a cab myself ...
here is my forum u ll find very useful info there : http://www.diyaudio.com/forums/showthread.php?s=&threadid=52976
.. the lowest string on a five strings bass is about 31 hz ... but u don need to find a woofer to handle 31 hz .. cuz in the most of famous ampeg cabs the response freq is startin at 55 hz ! ..
lol . it s concern to what kind of music u wanna play ...
so if it s hard for u to find a woofer to handle 31 hz forget it ... just try to find some good driver to handle 55 hz up ... i suggest EMINENCE ( eminence kappa or kappa pro )... cuz some great company like ampeg use the eminence drivers in their cab ! ...
but if u still want to have a full range respond , use a 18" or 15" driver w a large cab for low freq and a 4*10" cab for harmonics ( and of course a horn driver if u want a full range ) , cuz a 18" driver or 15" cant respond well in harmonics ...
if u wanna use this amp for practice use 2*10" or 2*12" cab at last and they don need to handle 31 hz , MOST of the famous bass combos like marshal ampeg , peavy , etc ...use one 10 or 12 " driver in their cabs ,and they never handle lower than 60 or 50 hz cuz it s really not necessary ... i m playin my ibanez sr3005 prestige model bass in my computer speakers !!! lol ,...
so don worry to handle 31 hz ... and here s the bass preamp i m usin for amp , it s a reall bass amp that made by a real bassist ! lol : http://www.albertkreuzer.com/start.htm ( bass jfet pre amp ) u ll not disapointed ...
so just search a lottttttt ... and try to understand how the famous manufacturer build their cabs and how is their freq response ...
if u think i can help u , just tell me .. i ll help u as i can , CUZ I REALLY KNOW HOW U DREAM FOR A BASS AND AN AMP AND WHAT U FEEL NOW ... ;)
 
Hi guys. I can't resist throwing my $.02 in. I played bass many many years ago and still pick one up now & then. There are a few things you need to keep in mind:

1) You are not trying to accurately REPRODUCE a recorded sound, you are trying to PRODUCE a musical sound.
2) Harmonic distortion (can) sound good. (See #1 above.)
3) Unless your pickup is mounted at the 12th fret, the amplitude of the fundamental will be way down relative to the harmonics of that vibrating string. This is at least partly why the benchmark Ampeg 8X10 can get away with what would otherwise be horribly poor, weak bass extension.
4) If you really want to produce the fundamentals, consider biamping: One true subwoofer with a low-pass crossover and its own level control, and a "regular" bass with a high-pass crossover.

Food for thought.

Thanks.
 
You guys are right... most of the production bass amps dont go very low

In my opinion that's pretty weak and I surely wouldnt buy one. But its really about how you want it to sound and not how everyone else wants it to sound.... Thats the whole point in DIY!

Trust me though... if you make a bass amp that can go down to 30hz and you have a 5 string people will be impressed when you hit the low B and it RATTLES EVERYTHING!

I think the amp itself should be clean... if you want distortion there are always effects pedals and other units to add prior to amplification. Just my opinion though
 
BassAwdyO said:
You guys are right... most of the production bass amps dont go very low

In my opinion that's pretty weak and I surely wouldnt buy one.

If you look at the bass rigs of the big name bass players, they are more often than not a one-off custom. They themselves are often not happy with production cabinets. But if you look at the amp rigs of famous guitar players, they are more likely made of of vintage amps with production cabs. In short, bass is a different kettle of fish and there's plenty of room for DIY.
 

Ron E

Member
2002-06-27 10:41 pm
USA, MN
Lowest fundamental on a 4 string bass is 41Hz. IF you look at a spectrum analysis of a typical open E, the 2nd harmonic is about +10dB over the fundamental. If you want to build a bass cabinet, you are best trading extension for efficiency and designing for a F3 around 55-60Hz using professional drivers designed for Bass guitar.

I have played a bass direct through HiFi speakers, and let me tell you, it sounds bad. Even a crappy little practice amp sounds better than bass through HiFi speakers. We didn't patch in any effects boxes because it wasn't convenient at the time, but whatever you do, you want to accomodate effects loops.

Get a synthesizer program off the net and make a tone with a bunch of harmonics, then progressively reduce the fundamental until you notice a difference - you will be able to almost completely eliminate the fundamental and the sound will be the same - try it and see.
 
Get a synthesizer program off the net and make a tone with a bunch of harmonics, then progressively reduce the fundamental until you notice a difference - you will be able to almost completely eliminate the fundamental and the sound will be the same - try it and see.

Have you done this with an extremely low note say <40hz where you can feel the fundemental rattle everything. I'm sure it might sound the same to your ears, but it wont feel the same to your body.


I have played a bass direct through HiFi speakers, and let me tell you, it sounds bad. Even a crappy little practice amp sounds better than bass through HiFi speakers.

Thats all perspective really. I'm sure it sounded pure and clean. Too clean for your tastes apparently. What does that practice amp have that the HiFi doesn't? Superior drivers and amplification? I hope not! Distortion, yes!
 
Yes, playing bass(or guitar) through the usual hi-fi speakers feels and sounds flat, boring, colorless, dead and uninvolving.
The amp and speaker is actually an important part of the instrument.

Its true that the harmonics are louder than the fundametal, but in my experience 4, 5 or 6 string bass sounds better, bigger, fatter and meaner if the amp/speaker can handle lower frequensies.

In smaller rooms you can get away with less, because of room gain. If it just for practice, you don`t need two 15", but for playing with a band, you need it.

Regards,
Peter
 
reply

I think something like a twin enclosure will be the best.

So you have an 18 inch or 15 inch in the bottom section which will be ported and tuned to 30hz for the deep bass.And a 10 inch or 8 inch above that in a sealed cab for the slap and thumb sounds.

Something like Eminence Legend CB15 or B15 for the sub bass and an Eminence Legend B102 or Eminence Legend 875 for slap/thumb sounds[higher harmonics to 8khz].
 
Yes, playing bass(or guitar) through the usual hi-fi speakers feels and sounds flat, boring, colorless, dead and uninvolving.

I can agree if one's playing style and instrument fit the above description !

There are basses that sound fine played through a mostly flat amplifying chain.

Furtermore I can't stand the live-sound of most bass players using max compression and played over cabs that emphasize the range around 100 Hz.
It is a shame that most musicians have bad taste regarding sound (guitar players being far worse than bass-players even).

Sorry for the ranting.

Regards

Charles
 

nate

Member
2004-06-07 10:42 pm
USA