Pioneer Project

[Fast1one]

Very soon (within a couple weeks) i will be making a pair of TLs for Pioneer B20 8s(http://www.partsexpress.com/pe/showd...number=290-045) found on parts express. Looking at the specs and reviews from people that have used them, i have decided to add two piezos per tower for upper reinforcement these here: http://www.partsexpress.com/pe/showd...number=270-011

Do you guys have suggestions for the resisters and caps I should use to wire two of them and the speaker to a ~4 ohm load? Also do you think you can look over the design I made and give me suggestions on that? The line length is 87 inches for reference and the driver is mounted 1/3 of the way through the line. Thanks a lot, this forum is awesome

BTW sorry for the image resolution, had to resize it

[Nelson Pass]

From the spec, these tweeters look to be about 6 dB hotter
than the B20's (which I think are more like 88 dB in reality) and
so I can't really see needing two of them.

You are definitely going to want to think about being able to
attenuate them and/or providing a high pass filter at about 10 KHz
or so. I would recommend a cap followed by a 2 resistor-in-
series network to ground, tapping the tweeter at the mid-point.
I would consider starting values at 1 uF and a pair of 4 ohm
resistors and take it from there.

[Fast1one]

Thanks for the suggestion...sorry if this is a little redundant, but im a bit of a newb when it comes to crossover networks...the way I understood it was Cap>Resistor>Piezo>Resistor>Ground...is that correct? Also how would I tame the harshness if any at all? Lets say from 18K and up? Thanks a lot for the help...

Anyone have suggestions for the cabinet?

[Nelson Pass]

I guess I could try describing this with a netlist:

Node 0 = Ground Node 1 = input

Node/Node/Part

1 / 2 / C

2 / 3 / R1

3 / 0 / R2

3 / 0 / Piezo

You will probably want to play with the values for R1 and
R2 to get your level, and as I suggested, 4 ohms each is a
good place to start.

I don't think you're going to experience much in the way of
harshness at 18K

And the box you pictured looks like a nice one.

[Fast1one]

Ahhhh now that makes sense...thanks a ton, once I get everything done Ill post my thoughts on the setup. This is my first home built speaker system, although ive been playing with car audio for a while now. Wish me luck hehe...

Any other opinions are welcome. Thanks!

[AdamThorne]

Neato project! I've seen a number of nice things said about the pioneer 8". Been wondering if anyone wanted to get exotic on the enclosure.

The project I read about before (Godzilla's project on the single driver website) talked about using the piezo with the pioneer, with tweaks and crossover. Is this what led you to choose the piezo? I understand Godzilla wanting to throw up the cheapest little speaker he could, but I have to wonder if maybe a little more budget for the tweeter might not make for a little easier / nicer integration. I've been particularly wondering about the ribbon tweeters that Apex Jr. has on his site. Not that I've actually heard either the tweeter or the woofer...

Anyway, I look forward to hearing about whatever you decide to do, and also the thoughts of others about interesting and fun directions to go with the pioneer 8".

A

[Fast1one]

Actually yes it was his idea that spawned this project...I wanted something cheap and effiecient...the pioneer isnt that effiecient but it sure is cheap We shall see how it goes...

[flg]

Well, I'm up for a B20FU project. I have a pair sitting right here in a (cardboard) box waiting for a good enclosure

[GM]

Greets!

FYI: http://www.partsexpress.com/pdf/piezo.pdf

GM

[GM]

Originally posted by flg
Well, I'm up for a B20FU project. I have a pair sitting right here in a (cardboard) box waiting for a good enclosure

Greets!

Well, if you're up for a simple pipe horn: http://www.zillaspeak.com/bib-pioneer.asp

GM