Eminence Beta 15 vs Delta 15 for Bassman cab

[benzomite]

Hello knowledgeable people at Talkbass!

I have a 70s fender bassman 100 amp and 4x12 cabinet. I'm going to convert the cabinet into a 2x15. I believe I've read all post related to this topic, and I've pretty much narrowed my choices down to either the Eminence Beta 15 A or Delta 15 A.

I have very limited understanding of thiele-small parameters etc, and I don't know how to use winISD, so I'm asking simple advice in layman's terms.

The cabinet is sealed, and has an internal volume of approximately 9 cu.ft. The enclosure size recommended for these drivers in a sealed cab is 1.6-2.2 cu. ft. for the Beta 15, and 1.3-1.5 for the Delta 15. My cab will have about 4.5 cu. ft per speaker. Is there any disadvantages to mounting the drivers in a cabinet that's bigger than the recommended size? I believe I've read that the 'ideal' enclosure size will be a lot bigger than the 'recommended' size..
And does the larger recommended enclosure size for the Beta mean that it will be better suited for a big cabinet like mine?

Given that they both could work in my cab, any opinions on the differences in sound and performance between the Beta 15 and Delta 15 would be highly appreciated!

I'm also a bit curious about whether the Eminence Legend cb15 would work and give me any sonic improvements compared with these?

The cabinet will be used for bass with the 100w bassman head.

cheers

[billfitzmaurice]

Delta 15. It's better in the mids, and the short xmax is no issue with the low power you have. BTW, the 'ideal' size for a Beta 12 is 27 cu ft, for the Delta 15 10 cu ft.

[will33]

Let me know how it turns out. I have a 135 I like the sound of. Had many different speakers under it trying to get "that sound" loud enough but aside from carrying a truckload of giant bins, failed every time. I'm in a more sane band now, intend on keeping it that way. Considering re-visiting the idea. Delta's look like they'd have just enough output, on paper anyway, for smallish gigs and stage volume elsewhere.

[benzomite]

Thanks for your quick replies, that's all I needed to know.
I'll go for the Deltas, and let you know how it turns out.

[JimmyM]

Originally Posted by will33

Let me know how it turns out. I have a 135 I like the sound of. Had many different speakers under it trying to get "that sound" loud enough but aside from carrying a truckload of giant bins, failed every time. I'm in a more sane band now, intend on keeping it that way. Considering re-visiting the idea. Delta's look like they'd have just enough output, on paper anyway, for smallish gigs and stage volume elsewhere.

Despite them not having as much xmax as the Beta, Deltas aren't wussy speakers. I've got them in my B-15 repro cabs, and I've slammed one pretty hard with a 300w amp and it took it and got way louder than I'll ever need. Don't know if I reached the 300w mark, but I had the amp's limiter tapping out before I had the cab farting. Plus they sound about identical to the 60's CTS speakers that Ampeg used. They're pretty loud speakers, really. The Betas might take a bit more but the Deltas take as much as I'd ever need.

[will33]

Originally Posted by JimmyM

Despite them not having as much xmax as the Beta, Deltas aren't wussy speakers. I've got them in my B-15 repro cabs, and I've slammed one pretty hard with a 300w amp and it took it and got way louder than I'll ever need. Don't know if I reached the 300w mark, but I had the amp's limiter tapping out before I had the cab farting. Plus they sound about identical to the 60's CTS speakers that Ampeg used. They're pretty loud speakers, really. The Betas might take a bit more but the Deltas take as much as I'd ever need.

Ya, I recall you discussing them in your B15 cabs, and I trust your ear. I don't know if I'm just wierd or what. Old guys who had to play bassmans and showmans because there wasn't anything else say they sucked....I like them. Not for grit though, for the kinda "warm but clean" bounce you get with a P-bass. You can't turn them up very far before you start to lose that. It isn't really finding a speaker that can handle much power, it's finding one that gets loud enough with very little power. I've gone round and round with this with little success but in the back of my mind, there has to be that better mousetrap out there somewhere.

[walls]

Originally Posted by billfitzmaurice

Delta 15. It's better in the mids, and the short xmax is no issue with the low power you have. BTW, the 'ideal' size for a Beta 12 is 27 cu ft, for the Delta 15 10 cu ft.

Would you recommend these for non ported cabs? or strictly ported?

I'm contemplating trading a 2x12 Fender cab I have for a buddy's 2x15. I may just trading one problem for another however.

[billfitzmaurice]

Originally Posted by walls

Would you recommend these for non ported cabs? or strictly ported?

I'm contemplating trading a 2x12 Fender cab I have for a buddy's 2x15. I may just trading one problem for another however.

Only for sealed. Qts is too high for vented, there are much better choices.