carvin ls1503 speaker swap

hobbes1 · #1 01-24-2012, 08:05 AM

i've searched around and asked question here previously about this cab. i decided to get one of the newer versions of this cab as i got it a reduced cost. it is a nice sounding cab but it can get farty below low E when pushed a little. i'm using a peavey classic 50/50 poweramp to run it.
i know that the consensus from the megathreads seemed to be: drop in a neo 15" replacement, but i don't want to fork out $300+ for one of those. can anyone comment on:

delta pro 15a, legend CB158, kappa pro15a or delta 15a

as to which might be the best replacement? i plan on increasing/adding polyester batting in the cab as need and a brace or two as well if needed.

a fEarful or avatar 153 isn't in the cards for me now but i have considered those for the future. adding one of the above woofers will still keep me well below the costs on these other two. thanks in advance.

anderbass · #2 01-24-2012, 09:52 AM

I'm not disagreeing a new speaker might help, but have you ruled out the possibility that your tube poweramp is simply overdriving on those louder/low notes?

BassmanPaul · #3 01-24-2012, 10:18 AM

Quote:

Originally Posted by anderbass

I'm not disagreeing a new speaker might help, but have you ruled out the possibility that your tube poweramp is simply overdriving on those louder/low notes?

+1 - This was surely my first thought as well.

hobbes1 · #4 01-24-2012, 10:22 AM

hi. thanks for the thought. i think that is not the issue as i have the fartiness without turning the amp all the way up. in fact, it can be farty on the low notes with volume on the amp turned to 5 and resonance all the way down to zero. the other notes are clear, it just seems to me that the speaker can not handle the low frequencies well. i have good control of my dynamics when playing and am not pounding the low B string either.

anderbass · #5 01-24-2012, 11:24 AM

I still think its your amp. (do you have it bridged to 100 watt output?)

Before spending any money, I'd suggest taking your bass/whole-rig to a music store and do some A-B comparisons using the stores 1x15 cabs with your 50/50 poweramp, and then try some higher powered amps with your current cab.

Just tell-em your not sure if you wanna buy a new amp or a cab, they'll let you try out some different combinations so you can be absolutely sure of what your problem really is...

lbwdog · #6 01-24-2012, 12:21 PM

I know they've gotten expensive, but a Kappalite 3015LF (or 3015) will sure put a grin on your face!

BTW, You can always sell the stock driver to recoup some of the expenditure.

hobbes1 · #7 01-24-2012, 12:22 PM

Ok. reasonable suggestion. thanks.
i have run the amp bridged (100w) and not bridged (50w). it's the lower freqs that cause the fartiness. notes below low E are the problem. i also used the same power amp on my mesa boogie 1516B cab (which i recently sold) and running everything else the same, did not get the fartiness in the low end. the boogie cab was superior to the LS1503 in that regard but also weighed more than double the carvin cab. this is what has led me to feel that a speaker swap is needed in the carvin.

hobbes1 · #8 01-24-2012, 12:26 PM

hi eric, yes i have seen that the prices have dropped off some and i could prob get them a little cheaper via a friend at a music store. still, more than i want to spend if i can get a a non-neo speaker that is better than what i have now.
this is why i'm hoping someone will chime in here that knows more about the in's and out's of this cab and speaker building software and could comment on which speaker is likely to perform best of the ones i referenced.

hobbes1 · #9 01-26-2012, 07:42 AM

bump for any more ideas/comments.

craig.p · #10 01-26-2012, 08:45 AM

You said the problem was with notes below low E. That tells me there are fundamental components in those notes that probably duck under that box's cutoff. Could be especially troublesome if you're using even a small amount of boost at the low end. Even more so if the knee points of your bass tone controls are very low -- say, 40 Hz or thereabouts. [1] Even more so if one or more bass controls are shelving rather than peaking, because you'd also be raising the gain down in the subsonic region. (Though even with a peaking control, the peak may be broad enough to run up the gain in the subsonic region anyway.) I think it's important to grab the internal dimensions of that box, subtract the volume displaced by the mid and tweeter, measure the port dimensions, and then, using the net volume, model the box with WinISD and any drivers you're thinking of installing. Run up the power in the model. I suspect when you do that you'll find you hit xmax at 60 Hz and below at an absurdly low power level. (60 Hz is just a wild guess. Could be 50, could be 70, whatever.) Plenty of info here and on the Web, and some at the vendor's site, about how to use that product. Make sure you use the pro/alpha version, however.

If you want to model the 1503 in its stock form, call Carvin, ask them which driver they're using in it (have your serial number handy so they know your 1503's vintage), and grab the specs for that driver to plug into WinISD.

Note 1: I used the plural in case you're boosting bass not just with the amp's bass control but also with an active preamp (stomp box or inside the BG cavity).

hobbes1 · #11 01-26-2012, 12:01 PM

thanks craig. good advise. only problem is i have a Mac not windows. is there any comparable ware online for macs? i know about ISD online but guessing it's not as complete as the pro/alpha?
thanks

BassmanPaul · #12 01-26-2012, 02:40 PM

Quote:

Originally Posted by hobbes1

thanks craig. good advise. only problem is i have a Mac not windows. is there any comparable ware online for macs? i know about ISD online but guessing it's not as complete as the pro/alpha?
thanks

You can run the program in a Safari window right from the website. You could use VirtualPC or Parallels. If you have a Intel Mac you can run Windows natively.

Written on my MacBook Pro.

hobbes1 · #13 01-26-2012, 03:03 PM

hi. yes, i can use ISD online but i was under the impression the pro/alpha was more comprehensive in it's abilities? the only one that will run in safari is the ISD online. not sure if that is what you are talking about?

will33 · #14 01-26-2012, 03:13 PM

Try a different amp with your carvin first. While the carvin speaker is no kappalite, it can handle your 50 or 100 watts. It might be something about that driver used in the ported design, an impedance spike your tube amp doesn't like. A different driver might help that but we don't know what the actual problem is yet. I doubt it's running out of excursion with less than 100 watts.

hobbes1 · #15 01-26-2012, 04:33 PM

hi will33. i had actually had opportunity to try it with a crown xls1000 bridged and still got similar results with the low end as with the peavey.
my main bass is a tobias growler from the gibson years. i usually play it with the rear bass control flat and the neck bass control flat or a little boost. same settings i had used with the old mesa 1516b cab. no problems with the mesa cab at all. i'm really just thinking that the LS1503 is using a 15" that isn't up to par with the performance i'm looking for.

John Bigboote · #16 01-26-2012, 05:34 PM

You're probably not going to like hearing this, but...

I picked up a new 1503 with the bed liner after reading all the great stuff here on TB, and I found it to be a total POS, and immediately sent it back to Carvin. After eliminating all variables (different heads, different cables, different cabs) I couldn't escape the fact that the cab just wasn't very good for bass apps. And it was surprisingly heavy, and an awkward carry.

IMO, swapping drivers isn't your best solution...

-jb

will33 · #17 01-26-2012, 05:43 PM

Quote:

Originally Posted by hobbes1

hi will33. i had actually had opportunity to try it with a crown xls1000 bridged and still got similar results with the low end as with the peavey.
my main bass is a tobias growler from the gibson years. i usually play it with the rear bass control flat and the neck bass control flat or a little boost. same settings i had used with the old mesa 1516b cab. no problems with the mesa cab at all. i'm really just thinking that the LS1503 is using a 15" that isn't up to par with the performance i'm looking for.

Then it's the speaker. Depending on how old yours is, it may not have the same driver as the earlier ones. Carvin switched suppliers from eminence to celestion somewhere along the way. I don't know what exactly they're using in there, but I haven't seen too much from celestion that was really up to snuff for bass. More useable for vocal PA type stuff......and of course, guitar speakers.

hobbes1 · #18 01-26-2012, 05:48 PM

john and will: thanks for the thoughts. you have summed up exactly my reason for requesting a little help. i also feel that the 15" is not up to par but the price was right and so i have the cab. now, i just need a little help, if anyone wouldn't mind, figuring out which of the speakers i mentioned in the original post above, would be the best replacement for this cab or a suggestion for an alternative. i don't want to pay neo prices either. i know it will never be a fEarful but i am willing to drop a little more money into the cab if i can improve the low end.
so, with that in mind: suggestions? much appreciate your time

will33 · #19 01-26-2012, 05:53 PM

Assuming you're happy with the rest of the sound, just not the woofer, the Eminence Legend CB158 models pretty nice in those cabs. Sure to be far better than what you have for around $130.

Just make sure you've eliminated the other possibilities before you buy one. Glue seams or dustcap coming loose on your current speaker, cabinet hardware rattling, etc.

hobbes1 · #20 01-26-2012, 06:11 PM

thanks. i'll check that one out!