Okay to use too small cab? (VAS)

[NighthawkGS]

Hi folks, quick question with hopefully quick answer.

What will be the negative effects of using a cab with insufficient VAS?

I want to put an Eminence bp122 12in speaker in my Eden ex112 cab. OEM whizzer speaker not working for me.

The Eminence bp122 frequency response chart looks awesome for me. I want lots of very high mids, 1000 to 2000 Hertz. Also want low and high mids, but I can put those back with EQ on my markbass LM 250, which will also boost the low end of the very high mids a bit. My sweet spot is 1300 Hertz.

EDIT: my second choice of speaker, eminence basslite S 2012, has much lower VAS, but frequency graph not so good for me. ALSO, not super interested in trying and returning a bunch of factory cabs that don't publish their specs. My experience so far has been that factory bass amps don't provide what I want.

Not concerned with overall sensitivity or efficiency, or a ton of low Bass. Not worried about blowing out speaker, it's for a light weight solution for practice and quieter gigs with classic rock band. One of the guitar players uses a 15 watt amp..

Thanks!

 

[Stumbo]

Here's a thread on the topic:
Thoughts on the Eminence Legend BP122

 

[Wasnex]

Hi folks, quick question with hopefully quick answer.

What will be the negative effects of using a cab with insufficient VAS?

I want to put an Eminence bp12 two 12in speaker in my Eden ex112 cab. OEM whizzer speaker not working for me.

The Eminence bp122 frequency response chart looks awesome for me. I want lots of very high mids, 1000 to 2000 Hertz. Also want low and high mids, but I can put those back with EQ on my markbass LM 250, which will also boost the low end of the very high mids a bit. My sweet spot is 1300 Hertz.

Not concerned with overall sensitivity or efficiency, or a ton of low Bass. Not worried about blowing out speaker, it's for a light weight solution for practice and quieter gigs with classic rock band. One of the guitar players uses a 15 watt amp..

Thanks!

I am not an expert on these matters, but I don't think you are asking a legitimate question as VAS is a driver parameter. Understanding Loudspeaker Data | Eminence Speaker

 

[NighthawkGS]

Here's a thread on the topic:
Thoughts on the Eminence Legend BP122

Thanks, read through that thread twice I think.

I neglected to mention in original post that some 12 inch drivers, such as the eminence basslite s2012, have a much lower VAS. I am wondering, what is the direct effect of using a high VAS speaker in small vented cab?

 

[Rick James]

High Vas in a small cab will give boomy midbass and weak lows. So will high Qts is a ported cab. This isn't something you have to guess about, use speaker modeling software to find out what the result will be. If that's not part of your skill set rather than take a shot in the dark you should try cabs until you find one you like and trade in the Eden towards it.

 

[BassmanPaul]

In order to work at it’s best a driver needs to be supported by it’s enclosure. It’s not just a matter of picking a new driver out of thin air and dropping it into an existing box. US Speaker is apparently very good at helping folk who want to achieve this. Measure the inside dimensions of the cabinet and any ports/vents it may have. Give them these measurements and they’ll give you a viable suggestion.

 

[fast slapper]

That's too small for either driver. Kappalite 3012HO will be 2nd to none in that box size with the amp you're using.

 

[NighthawkGS]

Thanks guys... Would still like to hear a quick summary of the actual effect of insufficient VAS. If that is possible?

Trying to find some rig solution that meets my seemingly unusual needs. Once I know what works, can expand and improve from there. Currently have couple of Markbass lightweight rear ported cabs, they are going back to GC unfortunately. Sound fantastic by themselves, but in rehearsal or gigs, need to turn them way up for big success.

All three of my heads have a knob called Contour/Enhance/VLF. I call them the suck knobs. Scooped mid-range? No!!!

I threw an Eminence bp102-4 into old dead SWR LA10 amp (cab). Almost right! Drummer and myself were laughing with joy this week. May try a bp102-8, frequencies look bit better.

The bp122 has a spike on frequency response chart right where I want it, 1300 Hertz... so, wondering what effect the grossly mismatched VAS will have with tiny (front) ported ex112 cab.

Thanks for reading this far!!!

 

[HaphAsSard]

ported

Considered sealing it?
The low-end profile below F3 would be about the same, and the upper bass peak would be reduced by quite a lot - at a quick modellage, to about +2dB vs. as high as +5dB, unless the existing port tunes the box very low to begin with. Conversely, if the tuning is around 50Hz, the peak would be severe as said, but the mechanical power handling quite good, and you would lose some if going sealed.
Anyway, a relevant thread:
Small Sealed 1x12: Best Driver?
Paging @voided3 for long-term impressions.

 

[voided3]

Considered sealing it?
Small Sealed 1x12: Best Driver?
Paging @voided3 for long-term impressions.

I found the BP122 effective in a small sealed box, but I didn't attempt to use it on gigs prior to swapping it for a Trace Elliot ELF 1x10" cab. The BP122 had good low end extension, but even for a guy like me who doesn't use tweeters, I felt it needed a tweeter to compliment it.

 

[NighthawkGS]

Thanks guys...

I will try plugging the long slot ports at bottom front, what the hell.

Yeah the BP series speakers fall off a cliff above about 2k Hertz. That's been the fly in the ointment so far for me.

I'm reading all about the KappaLites. Too much money and way too much wattage, but frequency response looks pretty good.

Not quite sure what midbass is. But all the undersized 12 in cabs I've tried have boomed quite a bit around 5th or 7th fret of E string.