Bottom Dweller help needed....

[Zippy]

Guys/Girls, I have two of these from my old days,



I have a Fender 75 designed by Paul Rivera that utilizes a 12" or 15" speaker at 8 ohms. The amp I own has a 12" Electro Voice speaker. I want to build an extension cabinet with one of my 15" E-130 8 speakers just for a different sound with that amp. My hope is I can plug it into the 75 extension and use it for a bass test cabinet. Is this possible?

Bass guys, what do I need for a true enough bass circuit just for testing? I've got a meter of course, but want to hear it as well. Do I need to buy/build another amp to match this 15" speaker and cabinet?

Thanks,
Zippy

[Elwood]

Zippy,
Have you seen this gearpage thread?
Andy Fuchs chimes in about 15's at the end.
Interesting posts that aren't too long -
http://www.thegearpage.net/board/archiv ... 68880.html

Make sure anything you build is overbuilt and ported properly if closed back(at least 3/4" quality ply with stiffening supports will make sure you
are shaking the air and not the cab walls.) .
Those JBLs are unforgiving earthquake engines in the low freq's.

[Zippy]

Elwood,

Yeah, I read that and thank you for the help. I do a bit of work on bass guitars of course, so I just wanted a little something a player could plug into for a quick listen. Researching, I found crazy crossover, compressor, and speaker/cabinet combinations that made my mnd numb.

Basically I guess the question is can I use my Ed Jahns designed Fender 75 to power the JBL loaded extension cab and expect a reasonable bass tone?

Zippy

[Elwood]

Elwood,


Basically I guess the question is can I use my Ed Jahns designed Fender 75 to power the JBL loaded extension cab and expect a reasonable bass tone?

Zippy

Yes, especially if you keep some overhead throughout. I'd keep the pre volumes low with the master vol almost dimed.

On some Fender circuits (dual showman) a flat response is achieved by setting the bass at 2-3, mids 7-8, treble 2-3 . Not sure if this applies toyour amp but it's worth trying to see if it's close to the right starting point.

You should be able to get good sound at lower volumes.

When plugging in the extension cab, does it disconnect the 12" ?

[Zippy]

Elwood,

Thanks for the response. I must manually unplug the 12" in my combo and plug the 15" extension cabinet in. It's quick and easy as they're both just 1/4" jacks and 8 ohms.

Zippy

[Elwood]

Cool,
No problems guessing internal wiring then which could affect the speaker load the amp wants to see.
That's why I asked.

cheers

elwood

[bassman]

I used a guitar amp for years to teach bass lessons. At low volume it should be fine even through the stock 12" speaker.
The 15 extension cabinet is just gravy.