2 way mini bookshelf w/bose fullrange and HiVi tn28 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 20th June 2011, 06:27 PM   #1
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
Default 2 way mini bookshelf w/bose fullrange and HiVi tn28

So I had a pair of the pictured pioneers laying around and was disappointed with the performance in the lower frequencies. I thought I could improve on it and make a good set for a SET tube amp. I chose the bose full range driver based on the TS parameters found at parts express. The problem I'm having however is that the sound is horribly shrill between 2-4khz. I have not installed a low pass filter since I'm awaiting the tweeters; however the crossover point for the high pass (lowest recommended being 1800hz) is going to leave a big gap in that range.

I opted to get genuine bose drivers (from a car) since they were way cheap and didn't have to wait (unlike P-E). Perhaps the characteristics of the bose are worse than the P-E replacements?

Parts Express Parts Express Replacement Speaker Driver for Bose 901 4-1/2" 1 Ohm : Questions, Answers, How To, FAQs, Tips, Advice, Answers, Buying Guide
Attached Images
File Type: jpg IMG_2695.JPG (351.6 KB, 209 views)
  Reply With Quote
Old 20th June 2011, 06:43 PM   #2
kevinkr is offline kevinkr  United States
diyAudio Moderator
 
kevinkr's Avatar
 
Join Date: Sep 2004
Location: Boston, Massachusetts
Blog Entries: 6
May need a shallow notch between 2 - 4kHz to make these sound right..

Do this with a parallel LRC network in series with the "full range driver."

Edit: Bose makes a lot of different 4" drivers, not sure that you can safely assume that the car drivers are anything like the ones being sold by Parts Express. Variants I am aware of include ones with 1,2,4, and 8 ohm voice coils, with and without magnetic shunts, different cone material formulations, and different spiders.
__________________
"Extraordinary claims require extraordinary evidence." - Carl Sagan
  Reply With Quote
Old 20th June 2011, 07:00 PM   #3
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
this is a 1 ohm driver w/a cloth surround (unlike the foam surround of the 901's and PE's). Paper cone w/o doping (unlike the 151's)

I've heard of impedance mismatch affecting tone (although I am not sure how); my test amp is a ss rated to run 4-16 ohm loads. I figure since the drivers are relatively efficient and am only cracking the vol. 1/4 of the way, it wouldn't hurt anything.
  Reply With Quote
Old 20th June 2011, 07:03 PM   #4
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
I have 2 pair of those Pioneers. I didn't listen to them much stock, but EnABLed they sound fine. You are never going to get much bass out of a 3" driver.

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 21st June 2011, 11:16 PM   #5
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
Quote:
Originally Posted by kevinkr View Post
May need a shallow notch between 2 - 4kHz to make these sound right..

Do this with a parallel LRC network in series with the "full range driver."

Edit: Bose makes a lot of different 4" drivers, not sure that you can safely assume that the car drivers are anything like the ones being sold by Parts Express. Variants I am aware of include ones with 1,2,4, and 8 ohm voice coils, with and without magnetic shunts, different cone material formulations, and different spiders.
I've tried two different crossovers (left overs from something) and did see an improvement. Granted these are not sized for the application.

One was a car crossover (what looks like a 2nd order Linkwitz-Riley)...I think it was sized for 4 ohm loads; 2x10uF caps, a big ceramic resistor and two identical inductors of unknown value.

The other one came from a home speaker, looks like a 2nd order xover....10&12uF caps, different sized inductors sharing a single ferrite core and big resistor like the other one.

The 1st one had less bass than the 2nd one, but the 2nd one's bass was too boomy. I guess i'll salvage the car xovers' circuit boards to fit my application; but I'm still affraid of the tweeter's Fo being so close to the xover point. Any advice?

I was initially hoping to just have a high pass filter (cap on tweeter) and that's it.
  Reply With Quote
Old 21st June 2011, 11:56 PM   #6
diyAudio Member
 
Join Date: Feb 2011
Location: Devon, UK
regardless of any other problems, how are you going to drive the driver, at 1 ohm, volts and amps are the same value!!! Surely, these drive units were meant to be used in multiples?
  Reply With Quote
Old 22nd June 2011, 12:38 AM   #7
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
yes, parallel array of 9 I think. I've gotta read up on impedance mismatch I reckon, but my luxman seems to be doing ok....should I stop before I burn something?
  Reply With Quote
Old 22nd June 2011, 02:19 AM   #8
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
Quote:
Originally Posted by kevinkr View Post
May need a shallow notch between 2 - 4kHz to make these sound right..

Do this with a parallel LRC network in series with the "full range driver."
Thanks; for posterity:
Car Audio - Parallel Notch Filter Circuit for Speaker Design

Now i just need to take some frequency response measurements. Any recommendations for quick and dirty freeware?
  Reply With Quote
Old 22nd June 2011, 02:33 AM   #9
just another
diyAudio Moderator
 
wintermute's Avatar
 
Join Date: Aug 2003
Location: Sydney
Blog Entries: 22
I'd definitely recommend holmimpulse!

Tony.
__________________
Any intelligence I may appear to have is purely artificial!
Some of my photos
  Reply With Quote
Old 22nd June 2011, 05:32 AM   #10
ching0n is offline ching0n  United States
diyAudio Member
 
Join Date: Jun 2011
Quote:
Originally Posted by wintermute View Post
I'd definitely recommend holmimpulse!

Tony.
can you use any run of the mill microphone? I'm having a hard time finding calibration procedures for something other than certain units.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
HiVi B3S in mini transmission-line DocLorren Full Range 55 25th September 2009 07:08 AM
FS: Vifa D25ASG and HiVi TN28 tweeters creek Swap Meet 0 9th January 2008 03:09 AM
Bookshelf fullrange advice wanted Rocky Full Range 56 26th June 2006 02:10 PM
8 - 8 inch Silver Flute and 8 TN28 HIVI jadenlinkletter Multi-Way 5 27th January 2005 02:58 AM


New To Site? Need Help?

All times are GMT. The time now is 01:26 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2