DIY Polk LSI7 ribbon tweeter

ramiro77

Hi everyone!
My name is Ramiro.
I´m from Argentina.

I´m close to start a new DIY project.
It´s basically a Polk LSI7 but instead using the ring radiator tweeter, i would use a matched pair of Fountek Neocd3 ribbon tweeters.

I wanted to start today with the project, but here is the question: i bought two Polk LSI7 midbass. I´ve heard from many friends and colleagues that polk´s midbass are the Peerless HDS134. Is this true? Because if it isn´t true, i haven´t got the T&S parameters to build the cabinet. And i don´t know where they got that information.

Sorry if there is any mistake in my spelling or something that you can´t understand.
I don´t like Google Translate so i have write everything by myself, and my english is not so good.

Ramiro.

Face

They may be similar to the HDS134, but they are not the same.

If you don't know what you're doing, you either have to buy the tools to make the necessary measurements or copy another existing design.

For some nice DIY designs check out these links.

http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm

http://www.humblehomemadehifi.com/index.html

http://www.htguide.com/forum/forumdisplay.php4?f=39

ramiro77

Thanks for your help Face!

It´s a pity...
I know what i´m doing, but i haven´t got T&S parameters, so i can´t build the cabinet for this midbass.

I thought this midbass was Peerless HDS134. I have T&S parameters for that.

There is any chance to get the LSI7 cabinet size? Or the liters of the cabinet? So i can use this midbass.

Face

You can use this to find out the T&S parameters: http://www.parts-express.com/pe/showdetl.cfm?Partnumber=390-803

FTGV

Even if you could obtain the T/S parameters they won't help with the all important crossover design. Good crossoveer development requires accurate frequency response and impedance measurements of the individual drivers in the enclosure being used and a good simulation software would be a huge help.

Face

Well said Fred.