Frugal-Horn Sub-Woofer - Page 3 - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 24th October 2011, 09:13 PM   #21
diyAudio Member
Join Date: Jan 2006
Location: North west England
  Reply With Quote
Old 31st January 2016, 08:08 AM   #22
AlexQS is offline AlexQS  United States
diyAudio Member
Join Date: Jan 2012
Location: Pacific Northwest
Originally Posted by planet10 View Post
I don't actually have a drawing (yet). The design process went like this (and probably over the phone): let's do a right triangular prism the height of the FH3 big enuff to give the 14-17 litres needed to accomodate a sealed SDX7. Shortly thereafter proto-units appeared at my door.

Here is a quick picture.

Click the image to open in full size.

The key to making a helper woofer work is extended top end (700-1000 hz minimum). Many dedicated subwoofers don't qualify. But there are tons of decent midbasses.

It would probably work a bit better as a deflector if the angle was as in the FH1, but we chose 45 degrees since it is a less complicated build.

One could also do it as a diamond shaped prism for more volume.

Hi, I need some advice on a pair of woofer boxes to go with a pair of FH3 with Alpair 7.3

I'm excited, just picked up a few sheets of 13 ply BB today

I happen to have four Eminence Eminator 2515. I got them because my goal at the time was efficiency, and they're 94dB/w/m with a low Fs, and were very inexpensive. Currently there's two in a rediciously huge (330 liter) bass reflex.

I'm thinking I'll try them in a sealed box, as I'm hoping to find crisper, cleaner, tighter, etc (I know subjective terms,... sorry -I listen to jazz, classic rock, no rap or hip/hop, and I'm not worried about movies at this point)

I'll try to keep this short:
I calculated some interior volumes for right-angle prisms, drew one up in sketch-up, etc:
  • Looks like if I put one in a sealed enclosure of ~80 liters I can have a Qtc of ~.704
  • If I go bigger, ~145 liters comes to Qtc .588
  • If I go aesthetically as large as I can, that would be 21inch, 21 inch, 29.7 inch, 60 inch tall, the interior volume will be 182 liters, with a Qtc of .551

    I'll attach a photo with some of the things I was looking at in Jeff Bagby's excel sim (includes some T/S of the driver).

    Can someone please make a suggestion? I'm sure a different driver would be a good suggestion, but for now I want to try to use the drivers I have on hand with miniDSP.

    Will a sealed arrangement work for this Eminator 2515 woofer? Should I try to figure out a tapped horn or something else instead?

    Looking forward to any suggestions about the best way to try to incorporate this driver to compliment Frugal Horns.

Attached Images
File Type: jpg diyaudio stealthwoof idea.jpg (113.2 KB, 259 views)
File Type: jpg Eminence Response.jpg (103.5 KB, 256 views)
  Reply With Quote
Old 31st January 2016, 08:35 AM   #23
diyAudio Member
Scottmoose's Avatar
Join Date: Mar 2005
Location: UK
Qtc is going to vary somewhat depending on the internal damping type & quantities. 145 litres with a fairly heavy stuffing density for e.g. should get you into the region of the 'optimum' 0.5 (critically damped). Gain is another issue; it won't be massive under anechoic conditions; F3 being 63Hz or thereabouts, notwithstanding step-loss etc. With lighter damping, you should still be in the Bessel region, so not too bad. If they're loaded into corners, assuming reasonably solid boundaries, the latter will become a non-issue, and you should get significant lift down to about 40Hz, before any EQ you may wish to add.
"'That'll do", comes the cry of the perfectionist down the ages.' James May -The Reassembler Community sites
  Reply With Quote
Old 31st January 2016, 07:12 PM   #24
jjcarr is offline jjcarr  United States
diyAudio Member
Join Date: May 2007
Location: Normandy Park, WA
Originally Posted by dbailey View Post

I'd like to hear from people who have matted a sub-woofer with Frugal-Horns. Did to find a sub what complemented the frugal's particularly well? Any subs that just flat out didn't mate with the frugals?

Any other full-range and sub comment/recommendations will be appreciated.

For what its worth, my amp is a RH84 with 12at7 driver, my source is a Squeezebox Touch. My listening room is 12' x 9' x 20' and my music listening preference is electric blues.

Thanks in advance four your input.

I've found the Martin Logan Dynamo, the original with 10" driver and 10" passive radiator works well if you want to add a good low-end. It's more musical than most subs and can be had on the used market for around $200-$250. I use a Grotto now myself, which is like the Dynamo with more adjustability.

Keep in mind, when you integrate the sub, don't let the signal that goes to the FH's pass through the crossover in the sub. Run it in a FAST configuration, where the speaker is full-range and the sub is just low-fill.
  Reply With Quote
Old 2nd February 2016, 02:01 AM   #25
AlexQS is offline AlexQS  United States
diyAudio Member
Join Date: Jan 2012
Location: Pacific Northwest
Thank you Scott. I'll plan my cut sheet for 145 liters and cross my fingers. I realize this isn't the most ideal driver for this application, but I'll let you guys know how it works out. A more appropriate woofer may be next years upgrade.

jjcarr, thank you too. Great suggestion to run the Alpairs FR.

Dave, you mention importance of crossing around 700 to 1000Hz. Why is this a key making it blend well? How low in frequency will FH3 play? I figure if they come down to 50 or 60hz, then I should cross an octave above at 100hz or 120hz. I think the 15" woofer should play up to at least 250hz pretty well, and that's slightly more than octave above the 120hz for the low pass. I have the flexibility of DSP, so I can experiment,...but good results are always found sooner when I follow good advice. Please let me know your thoughts about crossing at 700 to 1000 vs crossing at 100 to 120hz range.

Thanks again.

  Reply With Quote
Old 2nd February 2016, 02:08 AM   #26
diyAudio Moderator
planet10's Avatar
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Originally Posted by AlexQS View Post
you mention importance of crossing around 700 to 1000Hz.
No. I meant the woofer needs to reach up at least that high au natural.

community sites,, ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 2nd February 2016, 02:47 AM   #27
AlexQS is offline AlexQS  United States
diyAudio Member
Join Date: Jan 2012
Location: Pacific Northwest
Oh I see. That makes sense. I might just be in luck! Looking at some measurements I took a while back, a near field, 1m on axis, and 1m windowed at 5ms; there all a little wavy, showing a droop around 250hz to 350hz, but it falls off a cliff at 1100 down 25dB by the time the frequency reaches 2000hz.

Thanks again for everything.
  Reply With Quote
Old 3rd February 2016, 04:18 PM   #28
diyAudio Member
Join Date: Feb 2005
Location: Elk Grove, California
Send a message via Yahoo to layertone
It has most certainly been a long while. I'd like to chime in! My favorite subs now have been tapped horns - very efficient & clean, something like the Tangband 30Hz tapped horn?

Tapped Horns
  Reply With Quote


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
Frugal Horn and Audio Nirvana Pemo Full Range 2 21st November 2010 05:43 PM
Frugal horn build djdaveysprocket Full Range 16 3rd May 2010 06:36 PM
fe 127 & frugal-horn mcr483 Full Range 2 26th December 2009 08:25 PM
Single Driver Horn Base Port from Frugal Horn EmergencyDpt Swap Meet 0 26th October 2008 01:24 AM
mikasa/spawn family/frugal horn lornie Full Range 11 15th June 2008 10:24 PM

New To Site? Need Help?

All times are GMT. The time now is 06:06 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2