Crossover point and Impedance. - 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 18th February 2012, 04:28 AM   #1
diyAudio Member
 
Join Date: Jan 2012
Default Crossover point and Impedance.

Hi Guys:

I have a question for you. I am looking at the Erse 2 way crossovers sold by Simplyspeakers that look very much like the Dayton sold by Parts-express. I think they are the same thing. They both have a jumper in the low pass to adjust it depending on the impedance of the woofer, 4 Ohms or 8 Ohms. Now, here is my question, when the jumper is at the 4 Ohms setting and a 4 Ohms woofer is used, the crossover point remains the same or becomes double?. If I get a 2500hz and I use it with a 4 Ohms woofer and set the jumper to 4 Ohms, will the crossover point remain at 2500hz or will it increase to 5000hz?.

Thank you very much.
  Reply With Quote
Old 18th February 2012, 07:13 PM   #2
Lojzek is offline Lojzek  Croatia
diyAudio Member
 
Lojzek's Avatar
 
Join Date: Feb 2012
Quote:
Originally Posted by Aguilabrava View Post
Hi Guys:

I have a question for you. I am looking at the Erse 2 way crossovers ...
Now, here is my question, when the jumper is at the 4 Ohms setting
and a 4 Ohms woofer is used, the crossover point remains the same
or becomes double?. ?.
Thank you very much.
In theory for the LP X-over point:

4 ohms woofer, jumper 4 ohms, Fc= 2500 Hz
8 ohms woofer, jumper 8 ohms, Fc= 2500 Hz
  Reply With Quote
Old 18th February 2012, 07:48 PM   #3
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
do not expect much of that
  Reply With Quote
Old 19th February 2012, 03:13 AM   #4
mdocod is offline mdocod  United States
diyAudio Member
 
Join Date: Dec 2011
Location: Black Forest, CO
Send a message via AIM to mdocod
Why not have a proper crossover at least simulated based on driver data? At least it would be a lot closer to ideal than throwing a one-size-fits-nothing pre-made unit at the problem.

I'd be happy to give a simulation a go if you are interested.. I've found that you can often build a decent x-over that is specific to YOUR drivers from good quality components for less than the cost of those off the shelf pre-made units.
  Reply With Quote
Old 19th February 2012, 05:08 PM   #5
diyAudio Member
 
Join Date: Jan 2012
Default Thanks, and more details...

Thank you all for your help. Here, I'll give you more details. Few weeks ago I purchased a Topping TP-60 amplifier. I had a pair of Cerwin Vega D-1 speakers I purchased 20 years ago but never used, I kept them in their original boxes until now. I wanted to use my new amplifier with these speakers since they are 4 Ohms speakers, even though Cerwin Vega specifications say 8 Ohms. I got them out of their boxes and connected them to the TP-60, they are in excellent condition, surrounds, everything is great because they were never used, but I didn't like the sound they produce, so I came here to ask if it would be possible to change the OEM crossovers with something else that would make them sound better. The answer I got was no. Anyhow, after that I decided to leave them alone and just get used to their sound, but few days ago I discovered that the tweeter in one of them was not sounding, and the one in the other was distorting and at medium/high volume levels would go on and off. At first I thought the tweeters were fried, but I took them off and connected them directly to the amplifier's outputs and try them at low volume and both sound perfect. The woofers sound perfect, so I figured it was the crossovers. Before I just wanted to replace them to see if I could improve the quality of sound, now I have because they went bad. I was checking and saw those I mention in SimplySpeakers.com and parts-express.com that have the jumper for the low pass filter. I don't know much about this, but they look better than the OEM crossovers that came with the speakers, the original crossovers look pretty cheap and basic, I believe I paid about $190 for these back in the 90's when I bought them, my guess is that CW installs something OK and production cost has a lot to do with it, but perhaps installing a crossover with better components could improve the sound they produce, and now I am forced to install something since they don't work. Right now I'm using my TP-60 with a pair of B&W DM-220 and the sound is beutiful, what a difference, I know that the CW will never produce the same sound, but in my opinion all they need to sound a little better is more separation, they sound muddy, the bass is much stronger than the high frequencies, so the sound is flat, the DM-220 in the other hand sound great, I can hear clearly all instruments, very clean. Can you help me?. I still want to fix the CW D-1, and improve them if possible.
Thank you again.
  Reply With Quote
Old 19th February 2012, 05:18 PM   #6
diyAudio Member
 
Join Date: Jan 2012
Default Cerwin Vega D-1 Components

I forgot to mention the components in the Cerwin Vega D-1, I guess you need to know this in order to help me, they have a 8" woofer with a part number in the back, 81W4, and their impedance is actually 3.6 Ohms, I don't have any more details on them, I contacted Cerwin Vega to request the specifics on these components but they never replied back. The tweeters are like this below, sold at parts-express:
Pioneer AHE60-51F 3-1/2" Horn Tweeter 270-050
They are what they call "bullet type horn tweeters", mine read 7.3 Ohms.
Thank you again.
  Reply With Quote
Old 19th February 2012, 05:48 PM   #7
Lojzek is offline Lojzek  Croatia
diyAudio Member
 
Lojzek's Avatar
 
Join Date: Feb 2012
Quote:
Originally Posted by Aguilabrava View Post
I know that the CW will never produce the same sound, but in my opinion all they need
to sound a little better is more separation, they sound muddy, the bass is much stronger
than the high frequencies, Thank you again.
Would it be too much trouble to take a photo of the X-over assembly ?
If your drivers work just fine without X-over and have their normal DC
resistance values, there may be something wrong with tweeter capacitor.
  Reply With Quote
Old 19th February 2012, 07:52 PM   #8
diyAudio Member
 
Join Date: Jan 2012
Default Crossover Pictures

Hi:

Here are the pictures of the crossover. This thing is very small, about 1 1/2 inches long by 1 inch wide, attached to the inside of back plate of the connectors.
Attached Images
File Type: jpg _DSC0001.jpg (969.3 KB, 163 views)
File Type: jpg _DSC0002.jpg (705.4 KB, 151 views)
File Type: jpg _DSC0003.jpg (649.0 KB, 142 views)
  Reply With Quote
Old 19th February 2012, 07:57 PM   #9
diyAudio Member
 
Join Date: Jan 2012
I have pictures of the back of the PCB, but for some reason I'm having problems uploading them. I will try to post upload them later.
  Reply With Quote
Old 19th February 2012, 09:49 PM   #10
AllenB is offline AllenB  Australia
diyAudio Member
 
Join Date: Oct 2008
Maybe they need to be shrunk before they'll accept?

Would you be interested in fixing the ones you have, assuming that's where your tweeter problem is?
  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
crossover point - effects of impedance? champ222 Multi-Way 6 17th November 2009 07:41 AM
Can you hear the crossover point of a speaker with a well-designed crossover? 454Casull Multi-Way 11 2nd April 2004 05:48 AM
Point to point crossover soldering Ilianh Multi-Way 9 24th December 2002 04:14 AM
A better crossover point Westrock2000 Multi-Way 9 26th October 2002 05:13 PM
Sub crossover point AudioFreak Multi-Way 2 31st December 2001 11:33 AM


New To Site? Need Help?

All times are GMT. The time now is 04:18 AM.


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