Go Back   Home > Forums > >

Headphone Systems Everything to do with Headphones

AM I CRAZY? DIY nearfield nude driver desktop headphone concept
AM I CRAZY? DIY nearfield nude driver desktop headphone concept
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
Old 16th March 2016, 05:29 PM   #1
CharlieLaub is offline CharlieLaub  United States
diyAudio Member
 
Join Date: Mar 2007
Location: Michigan
Default AM I CRAZY? DIY nearfield nude driver desktop headphone concept

I think I have a crazy idea... or maybe not so crazy (but for DIY only!). Read on for details...

I've often espoused the use of a nearfield driver for the "ultimate fidelity" subwoofer. Assuming this would be used when you are seated in one place only (e.g. at the computer) for music listening, the idea is this:
  • Construct a means to place a large-ish (e.g. 12 or larger) diameter driver right behind your head or as close as possible to this location.
  • The driver is mounted in a minimal open baffle or very shallow open-rear baffle-and-2-sides frame.
  • Because of the driver diameter and the proximity of one's head to the driver, you are in the nearfield. As such, the response will be essentially the infinite-baffle response of the driver.
The idea is that the "ultimate" bass extends low in frequency, is free of cabinet resonances and small-box-distortion, and has no peaks and valleys from room modes. About the only way I know of achieving this apart from being in a very small space like a car cabin is via the nearfield method. I happen to have the perfect driver for this - a 15" free air type subwoofer with Qts=0.7, Fs=20Hz, and 15mm Xmax. If I listen to this in the nearfield the response should be essentially the infinite-volume, closed box response! Wow. So that would cover the bass nicely.

I started wondering to myself lately if this concept could be extended to the full audio spectrum, that is to add a driver on either side of my head near my ears. If the drivers are large enough in diameter, I would again be in the nearfield (up to some relatively high frequency at least) and I would be creating something like an open-back headphone but with completely open-air drivers. Is this a crazy idea? Not sure, I have never attempted something like this. I am concerned that above 1kHz or so, some odd effects from the interaction of my head and the driver (e.g. interference) will take place and the frequency response will be anything but smooth. Also, there will be no way to measure the response (I like to measure) so I will need to adjust any FR irregularities by the "seat of my pants" (e.g. by guessing).

Can anyone recall something like this - a full range nearfield "listening station"? Could this bring some real high fidelity in a DIY-only package? I might have to build a "listening throne" (e.g. a chair-and-speaker contraption) test bed.

Any thoughts on driver selection (size, type, etc) for full-range nearfield listening are welcome. What is the best way to implement this idea?
__________________
Visit my Audio Web Page <<--CLICK TO LEARN MORE-->> Get my LADSPA plugins
  Reply With Quote
Old 16th March 2016, 05:36 PM   #2
billshurv is offline billshurv  United Kingdom
diyAudio Member
 
billshurv's Avatar
 
Join Date: Mar 2014
AM I CRAZY? DIY nearfield nude driver desktop headphone concept
SubPac S2 - TheSubPac.com wear the sub?

If you are not careful you might end up re-inventing the 'egg' chair Modern Pod and Egg Chairs For a Retro Look | Decorating Room
  Reply With Quote
Old 16th March 2016, 05:44 PM   #3
CharlieLaub is offline CharlieLaub  United States
diyAudio Member
 
Join Date: Mar 2007
Location: Michigan
Quote:
Originally Posted by billshurv View Post
Hey, that's a cool product. They mention they use "tactile" (transducers) like a Bass Shaker. I'm thinking more along the lines of an actual direct radiator driver application (since I have a few of these!)...

Quote:
Originally Posted by billshurv View Post
If you are not careful you might end up re-inventing the 'egg' chair Modern Pod and Egg Chairs For a Retro Look | Decorating Room
Ah yes, maybe the wicker version... Well, no, I was thinking more like something with a baffle running from the floor up, behind my "chair" seat, and ending just behind my head. The two "arms" sticking out from there to hold drivers on either side of my head. The only challenge I see with this arrangement is that I couldn't move my head from side to side much without bumping into one of the drivers placed there... Maybe if I came up with a counterbalanced positioning system with some kind of headgear-strap contraption to keep the drivers and head in a relative alignment... See, CRAZY!
__________________
Visit my Audio Web Page <<--CLICK TO LEARN MORE-->> Get my LADSPA plugins
  Reply With Quote
Old 20th March 2016, 04:28 PM   #4
Grasso789 is offline Grasso789  Germany
diyAudio Member
 
Join Date: Mar 2016
Location: Juelich
Hi, for my desk and workbench speakers i use 13 x 7 cm oval fullrange drivers also for the beaming they provide. Still, the remaining reflections off the walls and table help me to understand where i am and not hurt myself. What works is much determined by practic, ergonomic issues, even tho man strives for the useless, exceptional. Thy idea fits into this frame, Charlie. Uli
  Reply With Quote
Old 20th March 2016, 05:03 PM   #5
rayma is online now rayma  United States
diyAudio Member
 
Join Date: Apr 2011
Quote:
Originally Posted by CharlieLaub View Post
Maybe if I came up with a counterbalanced positioning system with some kind of headgear-strap
contraption to keep the drivers and head in a relative alignment... See, CRAZY!
You think that's crazy?
Jecklin Float electrostatic headphones | Stereophile.com

Last edited by rayma; 20th March 2016 at 05:05 PM.
  Reply With Quote
Old 23rd March 2016, 04:15 AM   #6
CharlieLaub is offline CharlieLaub  United States
diyAudio Member
 
Join Date: Mar 2007
Location: Michigan
Still thinking over how to execute this concept...

I think what I would prefer to do is integrate the nearfield system into a chair like a chaise lounge, for instance something like the Corbusier LC4 chaise. I have a Wassily chair that I rarely use that I might also use. The advantage of a reclined chair is that the height of the sub, which should be behind but still near the head, is lower. This makes the height of the drivers lower and reduces the size of the base.

Once the geometry is fixed I can build the fixture to hold the sub and the two side speakers that are placed on either side of the head.

Apart from the large subwoofer that I can use for this project, I am trying to figure out what might work best for the "side" drivers. I have a pair of 3.5" TangBand full range speakers that would work, but I think that something larger woudl work better, because the nearfield extends farther out away from the plane of the driver mounting ring. So, for example, this 8" full range driver with whizzer cone might be a good option from Parts Express. Not cheap, however.

Then there is the small problem that this system will lack all room reflections because you are sitting in the nearfield. I think many people underestimate the importance of room reflections in generating an "enhancement" of the stereo image and increasing depth and width of the sound stage. Well, I will have to add these into the sound sent to the drivers, artificially. I could do this by mixing in a delayed copy of the sound but that would be rather crude. Instead I may put into use a venerable Sony TA-E2000ESD preamp that I have lying around. This can "synthesize" room reflections and add them to the audio. It also has a multiband PEQ as well as a mono subwoofer output with crossover (fixed at 80Hz, 18dB/oct). If the nearfield response of the drivers is flat enough, I might only need this kind of correction to provide relatively flat response from the system.

So, some food for thought. This could turn out to be something interesting...
__________________
Visit my Audio Web Page <<--CLICK TO LEARN MORE-->> Get my LADSPA plugins
  Reply With Quote
Old 23rd March 2016, 05:54 AM   #7
Fast Eddie D is offline Fast Eddie D  United States
diyAudio Member
 
Join Date: May 2010
Location: Skokie Il
Quote:
Originally Posted by billshurv View Post

If you are not careful you might end up re-inventing the 'egg' chair Modern Pod and Egg Chairs For a Retro Look | Decorating Room
That's the first thing I thought of. Sitting in one was like listening to headphones without having to wear them. And they played loud with next to no power.
  Reply With Quote
Old 23rd March 2016, 08:17 AM   #8
sgrossklass is offline sgrossklass  Germany
diyAudio Member
 
sgrossklass's Avatar
 
Join Date: Nov 2004
Location: Germany
The one thing that strikes me as problematic about a project like this is the issue of sweet spot. You may end up so close to the drivers that moving your head by a few inches could affect frequency response and relative levels more than you like. Making your best impersonation of a statue does not sound like the ideal way of listening to music to me...
  Reply With Quote
Old 25th March 2016, 02:21 AM   #9
marsupialx is offline marsupialx  United States
diyAudio Member
 
marsupialx's Avatar
 
Join Date: Mar 2004
Location: Kansas City
There are fake heads with microphones that one could use for measurements, if one was so inclined. I've held raw drivers in close proximity to my head that sounded great!
  Reply With Quote
Old 27th March 2016, 04:20 PM   #10
CharlieLaub is offline CharlieLaub  United States
diyAudio Member
 
Join Date: Mar 2007
Location: Michigan
Quote:
Originally Posted by sgrossklass View Post
The one thing that strikes me as problematic about a project like this is the issue of sweet spot. You may end up so close to the drivers that moving your head by a few inches could affect frequency response and relative levels more than you like. Making your best impersonation of a statue does not sound like the ideal way of listening to music to me...
This is true but it depends on the size of the driver. This is because the nearfield extends out from the driver a distance that corresponds to some fraction of the width of the driver where it starts to transition to the far field. If I can use two large drivers they do not need to be that close to the head, giving one some freedom of movement. In any case, this isn't a system that one would use to do anything else besides listen to 2-channel audio while lounging in a chair. The listening position is fixed, and therefore so is the listener. The advantage is that the nearfield positioning should essentially eliminate all room interaction (for better or worse) much like a good headphone set, but can include real tactile bass that the whole body can feel from the subwoofer. I'm hoping that with larger drivers the frequency response could be flatter than many headphones can achieve because of the lack of a sealed cavity between the driver and the head.
__________________
Visit my Audio Web Page <<--CLICK TO LEARN MORE-->> Get my LADSPA plugins
  Reply With Quote

Reply


AM I CRAZY? DIY nearfield nude driver desktop headphone conceptHide this!Advertise here!
Thread Tools

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Desirable traits for nearfield/desktop setup Pallas Multi-Way 25 26th November 2013 01:21 PM
FR plan for desktop/nearfield? uFonken? mMar-Ken70? matt_garman Full Range 6 17th August 2012 02:14 PM
Desktop headphone setup advice roadlesstraveled PC Based 2 15th November 2011 11:54 PM
Burr Brown TI, driver DIY parts crazy sale! jazzy Swap Meet 8 19th May 2010 12:53 AM
Desktop Bipole Concept: Fact or Fantasy? roadsterdriver Full Range 3 11th September 2009 10:30 PM


New To Site? Need Help?

All times are GMT. The time now is 05:11 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Copyright ©1999-2021 diyAudio
Wiki