I have a bass cab with a 15" speaker that is no good. I beleive it is a homemade cab. I was going to replace the speaker with an Eminence Deltalite 2515 I. The cab is 25"w x 22"h x 10'd with a 2 3/4" dia. x 4 1/2" long port. Would it be OK to just change the speaker? Or should I enlarge,add or modify the port. Any help would be greatly appreciated. Thanks
Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
15" speaker replacement & port ?
- Thread starter markman
- Start date
The original Deltalite 2515 (I) is a terrible driver. Avoid it.
The right way to replace your driver is by figuring out the net internal volume of your cabinet, then getting the closest matching driver.
Link Removed
If you have Excel, you can use this tool to select from more than 1,000 drivers. You can sort by brand, box volume, etc.
The right way to replace your driver is by figuring out the net internal volume of your cabinet, then getting the closest matching driver.
Link Removed
If you have Excel, you can use this tool to select from more than 1,000 drivers. You can sort by brand, box volume, etc.
Did you mean the 2515-II driver? Eminence has some published designs for that driver at their website, including one with 2.3 cubic foot internal volume. The recommended port is 4 inches in diameter, by 5.4 deep. Your exising port is small enough to cause serious chuffing if that speaker is played loud, assuming the driver has any reasonable sensitivity.
It is worth opening up the cab and seeing what the driver is. What's no good about it? Blown? Or just bad sound?
It is worth opening up the cab and seeing what the driver is. What's no good about it? Blown? Or just bad sound?
Avatar has the Deltalite 2515 I & the Eminence 15 inch Kappa PRO LF in their overstock section. Being a homemade cab, I didn't want to put alot of cash into it unless it would turn out good. Would the Kappa pro LF be any better? What is chuffing? If I figured right, my cab is about 3.15 cubic feet (2.08 x 1.83 x .83).
Buzzing can be a little tricky to pinpoint. It very well could be the speaker, but it could also just as easily be the cab. I would open it up and check the speaker model for starters. Then check alll joints for possible movement inside the cab. Tighten the speaker into the cab and try it again. It could also be a grill that rattles. While you're at it block the port with a towel to make sure it isn't a chuffing noise.
I just checked your cab dimensions in Winisd. I am assuming you gave the interior dimensions based on your cab volume calculations. It appears your port is tuning the cab to about 28 hz. That would probavly rule out chuffing because the tuning is too low to be effective with most pro sound drivers that I'm aware of.
If you decide you need to replace the driver I would recommend the Kappa pro15lf only because I have experience with it and I think it is a very good quality driver. I would change the portint to 2 ports that measure 3 x 3.75 to give you about a 45hz tuning. This particular tuning with this driver is a good area for bass extension, good group delay, and good protection of the driver from unloading below box tuning.
Of course all of these calculations are out of the window if your box dimensions are actually outside dims.
I just checked your cab dimensions in Winisd. I am assuming you gave the interior dimensions based on your cab volume calculations. It appears your port is tuning the cab to about 28 hz. That would probavly rule out chuffing because the tuning is too low to be effective with most pro sound drivers that I'm aware of.
If you decide you need to replace the driver I would recommend the Kappa pro15lf only because I have experience with it and I think it is a very good quality driver. I would change the portint to 2 ports that measure 3 x 3.75 to give you about a 45hz tuning. This particular tuning with this driver is a good area for bass extension, good group delay, and good protection of the driver from unloading below box tuning.
Of course all of these calculations are out of the window if your box dimensions are actually outside dims.
You could alternatively (is that a word?) add 2 more ports of the same size as your existing one for a cab tuning of about 48hz. That is still well within reason and would offer you much better bass extension than your current setup.
Before you spend any money on that cab think about buying a cab from somebody who knows what they are doing. If the cab doesn't match the driver it will sound like JUNK, plain and simple. Companies like Avatar computer optomize their cabs for the speakers they put in them.
GreyBeard said:
The avatar cabs are no where near the optimum cab size and tuning frequency for the used drivers. They are in the size they are because of practical and economical reasons. Same size cab for the 1x15, 4x10 and 2x12...
There is no way a good computer program designed those boxes. Im not saying they sound bad (I have never played one) but they are not designed right IMO.
If that is the only port in your cab I would seriously look at design programme, I think that it will recomend a minimum of 4" diametre for a single port in a 15" cab.
The dimensions I listed above, 25"W x 22"H x 10"D, are the inside of the cab. There is fiberglass insulation lining the cab. There are no markings on the speaker, so I can't tell what it is. I'll post a picture of the speaker later and see if anybody can recognize it.
MuzikMan, I'm thinking of pluging my existing port and putting the 2- 3" x 3.75" ports. I don't have the room to enlarge the existing port to 4".
Thanks for all the help!
MuzikMan, I'm thinking of pluging my existing port and putting the 2- 3" x 3.75" ports. I don't have the room to enlarge the existing port to 4".
Thanks for all the help!
The buzzing could be the under-sized port. It could also be air leakage past the driver flange (been there done that on both accounts). I am not sure how good a seal you are getting with the carpet in there like that. It really has to be a good seal, like a rubber gasket.
So long as your port is not long enough to touch the back of the box, once you choose a diameter, you can tune it by trimming or adding length.
Multiple smaller ports should be OK. You can use WinISD to help design the port. Once it gives you a port diameter, you turn it into an area, and make sure your collection of ports adds up to the same area. Make the length the same as what WinISD gives -- don't divide it up. A port tuning of around 50 Hz is a good starting point if you play 4-string.
To design the port tuning frequency, you can throw in any driver into WinISD, because the port dimensions don't depend on driver parameters. For instance a 50 Hz port will be the same size and length regardless of driver. It does depend on box volume.
So long as your port is not long enough to touch the back of the box, once you choose a diameter, you can tune it by trimming or adding length.
Multiple smaller ports should be OK. You can use WinISD to help design the port. Once it gives you a port diameter, you turn it into an area, and make sure your collection of ports adds up to the same area. Make the length the same as what WinISD gives -- don't divide it up. A port tuning of around 50 Hz is a good starting point if you play 4-string.
To design the port tuning frequency, you can throw in any driver into WinISD, because the port dimensions don't depend on driver parameters. For instance a 50 Hz port will be the same size and length regardless of driver. It does depend on box volume.
billfitzmaurice
Commercial User
- Sep 15, 2004
- 16,860
- 278
- 76
- Disclosures
- Owner, Bill Fitzmaurice Loudspeaker Design
I don't know what it is but it appears ancient and quite likely is a hi-fi driver, not pro-sound. That would jibe with the very low tuning frequency of the box. It was probably made for DJ work.markman said:
billfitzmaurice
Commercial User
- Sep 15, 2004
- 16,860
- 278
- 76
- Disclosures
- Owner, Bill Fitzmaurice Loudspeaker Design
Major mistake. The Kappalite 3015LF weighs less than half what the KPro does and will take twice the power before exceeding xmax. In short, the KPro is obsolete.markman said:
That might be true but he can get a brand new 4 ohm Kappa Pro15lf for $77 delivered right now.billfitzmaurice said:
Markman..
There are ALL KINDS of really reputable used speakers with PLENTY of legit specs listed on eBay all the time. Sometimes you can even score a 'twofor' when someone is just so anxious to unload his current cab and load in new upgraded bass speakers.
Yeah that looks like a HiFi speaker alright. Your cab looks pretty small too, you gonna get the bass response you need with such a small internal space for that freq range?
There are ALL KINDS of really reputable used speakers with PLENTY of legit specs listed on eBay all the time. Sometimes you can even score a 'twofor' when someone is just so anxious to unload his current cab and load in new upgraded bass speakers.
Yeah that looks like a HiFi speaker alright. Your cab looks pretty small too, you gonna get the bass response you need with such a small internal space for that freq range?
The Kappa Pro 15lf will have an F3 of 47 hz in a 3cu. ft. box tuned to 45hz. That's pretty darn good for a box that size if you ask me.
Sorry that I'm gushing about that particular driver but I really think it is a very good quality speaker and you can't go wrong at that price.
Sorry that I'm gushing about that particular driver but I really think it is a very good quality speaker and you can't go wrong at that price.
billfitzmaurice
Commercial User
- Sep 15, 2004
- 16,860
- 278
- 76
- Disclosures
- Owner, Bill Fitzmaurice Loudspeaker Design
It's also excursion limited at 250W in the area of highest demand, 60 Hz, and weighs 15 pounds more than the Kappalite. Saving $50 amounts to $2.50 a year over the average life-span of the driver. I'd rather save the 15 pounds, at 3AM the fifty bucks won't seem nearly as significant.MuzikMan said:
