vented vs closed cabinets in bass amp construction?
#975680 - 14/03/12 12:50 PM
i have a friend i am recording some guitar clips for demonstrating the sound acheivable
with a guitar pick up he made. he is now building a bass amp and he has emailed me the
following question -
reevo, im designing an amp speaker cabinet for an
eminence ca2010 bass speaker, theres a downloadable spec on thier web site
eminence.com whats the difference between a small vented cabinet & a small
closed cabinet....in terms of sound ?.this is for a bass driver . theres also mention of 2 holes in the vented , 1 at 4" diameter & a 2nd at 7.5" diameter ?
does the larger one need to be front mounted? i dont understand it . can you help?
im using this with a wal bass which is a modern sounding bass with very high &
low outputs , have a look on their site ... walbasses.co.uk theres a bit about
the preamp & filters in the instruments & how low they go. im ordering the
wood (oak) 20mm thick for the construction as its quite cheap here & natural
woods sound better than composites . ive figured out the internal area from the cubic
foot guide from eminence , just dont know wether to build a vented or closed cab.
cheers , mh
my understanding of a vented cab is that it sounds better
with low end freq as it pushes the sound generated from the rear of the speaker out of the
front. is this correct? I have never built anything like this before and thought someone
one here may be able to explain a little better than me.
Re: vented vs closed cabinets in bass amp construction?
#975784 - 14/03/12 11:11 PM
Alex, the advantage of a reflex enclosure is that it gives more LF output for a given
size of cab but at the expense of a worse, often much worse response in terms of
"flatness" and (for the hi fi buffs) a worse transient response. Even then the extra
output will only be realized if cab and port follow very closely the drive units
parameters, i.e. you need a makers drawing and stick rigidly to it! Ported cabs also
"unload" the speaker for VLF and this can lead to speaker damage.
absence of a detailed drawing go for the biggest sealed cab you reasonably can. I
would not use natural timber and oak is a bugger to work with! MDF is acoustically better
as it is dense and inert but will be too heavy for a portable speaker cab. Marine grade
ply and plenty of bracings should do the trick.