Which replacement speaker do I need??

[Wooks79]

SO I blew a speaker, and I dunno what I should get to replace it, as I always keep reading that they need to be specific for the dimensions of the cab etc... and I know nowt about all that!

The speaker in question is a Celestion Sidewinder from my Marshall 1525 2x15, 250watts 8ohms.

I cant seem to find a straight replacement Celestion Sidewinder anywhere, so what do I need?

I would Ideally like to replace both speakers together and go with some Neodymium if I could to let some of the weight go.

Help me basschatters, you're my only hope... *Fzztk* Help me basschatters, you're my only hope...

Edited June 9, 2011 by Wooks79

[Moos3h]

I'm yet to hear a situation where an Eminence Kappalite 15" hasn't sounded, ahem "teh awesome1!1" so my vote would go for that.

Not the most scientific of answers, you'll understand.

[Bill Fitzmaurice]

[quote name='Wooks79' post='1263326' date='Jun 9 2011, 04:47 PM']SO I blew a speaker, and I dunno what I should get to replace it, as I always keep reading that they need to be specific for the dimensions of the cab etc..[/quote]You posted no dimensions, so no answer is possible. Complete internal dimensions, including ports if there are any, and what you're using for an amp are required.

Edited June 9, 2011 by Bill Fitzmaurice

[Wooks79]

[quote name='Bill Fitzmaurice' post='1263387' date='Jun 9 2011, 10:39 PM']You posted no dimensions, so no answer is possible. Complete internal dimensions, including ports if there are any, and what you're using for an amp are required.[/quote]

As I said in my original post, I know nothing about all that part of it, so don't know what dimensions you need, or what difference the amp being used makes, cos I use a few different amps at different times with this cab...

Thats why I thought it best to post the details of the cab that I do know off hand, like model number, and what speaker is in there at the mo to be replaced... I thought someone may know of a direct replacement to a celestion sidewinder.

The cab is in the studio, and I am at home, so cant go measure...

I just thought it might have been easier than it obviously is

[stevie]

The Sidewinders were quite good speakers in their day. They were introduced in the mid 1980s and were based on Electrovoice designs. You should be able to pick one up on eBay for not very much money, but you'll probably have to wait a while for one to appear.

Still, if you follow Moos3h's advice I'm sure you'll be fine. If you would like someone to double check the technical aspects of the design, post the internal dimensions of the cab (to get the internal volume) and the dimensions of the ports (internal diameter and length). But it certainly looks like a fairly standard box and you should be perfectly OK fitting a pair of Kappalite 15s in there. As these seem to be be quite expensive now, it might also be worth looking at the equivalent B&C or BMS, which will sound better if you don't mind investing a bit more dosh.

Edited June 10, 2011 by stevie

[Wooks79]

Right, finally got the measurements, so please, if anyone with the magic can help?

the cab is the same space for both speakers, the space is -

42cms High
63cms Wide
33cms Deep

It has a round hole at the front of each section with a diameter of 12.5cms

The shelf that divides the sections has 2 rectangular holes, 17.5cms by 12.5cms

Here is a picture of the cab -



SO can anyone with whatever computer programs or brilliant knowledge please tell me which bass speakers to buy to replace these?

Original spec still applies, each speaker would ideally be Neodymium, minimum of 250 watts, and 8 ohms per speaker.

Thanks!

[Balcro]

Yes, I think Moos3h is right. I've had a bit of a dabble at this with winISD and I reckon an Eminence Kappalite 3015 (not the LF variant) will fit the bill. It's nominal overall power handling is 450 watts and it's very efficient; like LOUD. It models quite well and even showed a rising bass output below 100Hz. Smoothing that bass out is relatively simple, but see if any other respondents agree with my assessment.
Didn't check the cost.

Balcro.

[escholl]

[quote name='Moos3h' post='1263344' date='Jun 9 2011, 10:02 PM']I'm yet to hear a situation where an Eminence Kappalite 15" hasn't sounded, ahem "teh awesome1!1" so my vote would go for that.[/quote]
This is also my recommendation.

Although, other options are certainly available.

[Bill Fitzmaurice]

Still need your amp specifics, as which you'll use makes a big difference.

[Wooks79]

[quote name='Bill Fitzmaurice' post='1294199' date='Jul 6 2011, 01:07 AM']Still need your amp specifics, as which you'll use makes a big difference.[/quote]

Really? How come? Surely speakers for a cab are speakers for a cab, according to the cabs dimensions, regardless of what amp you use?

Excuse me if I'm being thick thinking that... I just don't get it, cos what I use now, may not be what I always use, and I don't plan on changing speakers out to swap amps...

Anyway, my current amps are in my sig - Ampeg SVT-3pro, Sound City b120 mk4 and an Orange Terror Bass 500. I'm sure there will be others in the future...

Thanks for helping.

[Bill Fitzmaurice]

With low power you want a hgher Q driver that delivers a humped midbass response, for adequate output. With high power you want adequate xmax to handle it, whereas with low power high xmax is unwarranted. And then there's the matter of impedance, being sure that it's appropriate for the amp. That's far more complicated than it seems on the surface; Ampeg is having some major problems with their mini-stack, as the load offered by a pair of the 2x10s is fundamentally at odds with the needs of the amp.

Edited July 6, 2011 by Bill Fitzmaurice

[Wooks79]

Might just sell this cheap since I've now decided to flog a hell of a lot of stuff to save towards a matamp.

[Balcro]

Reading between the lines, I think Bill is cautiously referring to the potential for damage that may occur to the amplifier
if your amp is not capable of operating into a 4 Ohm load. Therefore he has asked you for amp details. He wouldn't want to
give you an unqualified recommendation on loudspeakers if your changes caused your amp to burn out

If you replace the speakers, you'll need two 8 ohm drivers. When wired in parallel - which is what you probably
have now - (check it anyway) you amp will see a nominal 4 ohm load. It looks like the SVT-3Pro is comfortable with that. I don't know if your other amps are the same. There's probably a reference to Ohms/Resistance in the forum wiki.

Balcro.

[Bill Fitzmaurice]

[quote name='Balcro' post='1294629' date='Jul 6 2011, 07:29 AM']Reading between the lines, I think Bill is cautiously referring to the potential for damage that may occur to the amplifier
if your amp is not capable of operating into a 4 Ohm load.[/quote]Not quite. Load figures are only vast generalizations, based on the DCR of the drivers used. Even with the same nominal load rating different cabs have very different loads, even when using the same drivers, as shown here:



This shows the same driver in a sealed and vented cab. A tube amp will be much happier with the lower average impedance load of the sealed cab, SS will be happier with the higher average impedance load of the vented cab. The inverse is also the case, and is likely the source of Ampeg's problem with its Micro VR SS head and sealed 2x10 cabs.

Edited July 6, 2011 by Bill Fitzmaurice

[Wooks79]

That's a lovely story bill, thanks

[Balcro]

[quote name='Bill Fitzmaurice' post='1294958' date='Jul 6 2011, 05:09 PM']Not quite. Load figures are only vast generalizations, based on the DCR of the drivers used. Even with the same nominal load rating different cabs have very different loads, even when using the same drivers, as shown here:

This shows the same driver in a sealed and vented cab. A tube amp will be much happier with the lower average impedance load of the sealed cab, SS will be happier with the higher average impedance load of the vented cab. The inverse is also the case, and is likely the source of Ampeg's problem with its Micro VR SS head and sealed 2x10 cabs.[/quote]

Further to your post No. #14 above:-

Wooks79 has a SS power amp section to his SVT3 Pro and its operated into a vented cabinet, which
displays that typical double peak impedance (red-line) plot. Therefore from your explanation,
can it be assumed that amp will be reasonably comfortable under such conditions?

Balcro.

[escholl]

[quote name='Balcro' post='1295388' date='Jul 6 2011, 11:13 PM']Further to your post No. #14 above:-

Wooks79 has a SS power amp section to his SVT3 Pro and its operated into a vented cabinet, which
displays that typical double peak impedance (red-line) plot. Therefore from your explanation,
can it be assumed that amp will be reasonably comfortable under such conditions?

Balcro.[/quote]
Any well-designed SS head will be fine with any cabinet type.

It's also worth pointing out that valve amps have been paired with vented enclosures successfully and without issue for many years.

A simple magnitude plot of the impedance doesn't quite tell the whole story, and to be honest I wouldn't worry about it too much.

[Bill Fitzmaurice]

[quote name='Balcro' post='1295388' date='Jul 6 2011, 06:13 PM']Further to your post No. #14 above:-

Wooks79 has a SS power amp section to his SVT3 Pro and its operated into a vented cabinet, which
displays that typical double peak impedance (red-line) plot. Therefore from your explanation,
can it be assumed that amp will be reasonably comfortable under such conditions?

Balcro.[/quote]SS is generally fine with all vented cabs, not so much with sealed cabs when run at the amp minimum load rating. The opposite is true of tubes. They'll run into a dead short without complaint, but aren't happy with some vented cabs, especially those with very low Q drivers, which have very high peak impedance values. Now defunct Basson is an example, well known for bragging on their very low Q drivers with 20 pound magnets, almost as well known for their cabs toasting output transformers as a result of same.