Advanced Loudspeaker Application Development Project

Multiple-Degree of Freedom Cavity Resonator System


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Welcome to the world of the most advanced bass-reflex loudspeakers!
Here are some sample drawings actually made and not tested. Models not tested are just for reference only.
Models actually made are selected ones that the autor believes that may be recommended for trial use.
There are some comments along with model descriptions.
On the other hand, preference is due to each of you. You are to determine if you make or modify presented models at your risk.
No satisfaction is guaranteed at all for each model, so that you determine if you go ahead or decline.
Generally speaking, the tested models have unique features that most of you have not yet experienced.
Therefore, it will be a joy to experience the world of multiple degree of freedom cavity resonators.
The author, myself, actually enjoyed and discovered that they are good for him.
It will be an interesting trial for you, if you have environment to manufacture complex models.

If you want some suggested models that have NOT been made, refer to archive.



This is the very first MCAP-CR model!
System configuration of this model is two-subchamber + four ducts.
Tangband's full range driver W3-517SB is applied, though not limited to.
Sound of this model is natural and this model generates considerablly low frequency down to approximately 50 Hz.
It is the easiest to assemble this model among all the MCAP-CR systems.

Original model was assembled with 14mm and 10mm thickness plates, because there were unused materials.
It does not have to be assembled as the very original.
Rev.2 equivalent system drawing are uploaded.

DU080a Rev.2 Assembly
DU080a Rev.2 Isometric Assembly
DU080a Rev.2 Cutting Plan

Original system drawing is below:
DU080a Original Assembly


This is a standard MCAP-CR with two subchambers.
Drivers' layout is unique. This layout is typical of QNDR(Quasi Non-DimensionalRadiator) models.
NDR(Non-DimensionalRadiator) system was developed by someone else, but, unfortunately, no details are not available now.
My friend let me know how the NDR works.
I tried similar but different drivers' layout to NDR.
I named it QNDR. Its effect is different from NDR; however, it realized unique sound field representation.
With tis layout, listner dose not care about where to stay.
This is very unique and will present position-free sound field.

Used driver models is Tangband's W2-802SE. This model was tested with Foster's FF57BK as well.
Both driver models perform well with this enclosure design.
This model should be set as high as practically possible.
Recommended installation is to suspend the system from ceiling in a spacious room.

DU050x4a Assembly (isometric)
DU080x4a cutting plan
Triangular section (recommended shape) rod should be pasted to corner in addition to plates.

Con Gioia

This model was designed for Fostex's FE83En.
This model has more than enough volume for 3" driver. 4" driver may be applied.
A hole of wall between subchambers is not necessary. It may be better not to make a hole here.
If this hole is made, this model is a type of AICC-CR, and not made, it is a type of standard MCAP-CR.
This model generates enough low frequency sound down to approximately 40Hz+.

Reference (sorry. It is in Japanese)
Visual structure. Thank you. Jason! Front View
Visual structure. Thank you. Jason! Rear View

TR080b / CBT080a / AIT080a

I made these three models to know difference among standard MCAP-CR, CBS-CR, and AICC-CR.

TR080b standard MCAP-CR Isometric Cutting Plan(AIT080a & TR080b)
AIT080a AICC-CR Isometric
CBT080a CBS-CR Isometric Cutting Plan(CBT080a)
Assembly All Models
Note that rod along corner needs to be prepared separately.

Each model has exactly the same appearace. Sounds are similar, but listners noticed some differences.
I recommend Standard MCAP-CR. Majority of audiences at my presentation chose CBT080a. My friend chose AIT080a.
In any way, they are interesting.
Note that assembling these models are extremely challenging. Good for master of handcraft.

5" models

TR130e/TR130e2 Author's Current Main Model

TR130e / TR130e2
I like 5" drivers. 5" drivers have enough effective area and moderate high frequency performance.
Most 5" drivers will be applicable to MCAP-CR.
Author is currently using Tangband's W5-1611SA and Feastrex's NF5Exciter models.
Fostex's highest end models may perform well with MCAP-CR.
TR130e Assembly
TR130e Internal View. (Thank you. Mr. Nakata)
TR130e Cutting Plan

TR130e2 Assembly
TR130e2 Cutting Plan

These two variations were not basic design change.
I wanted to make two sets of TR130e, but I had to redesign because 4" paper pipe became unavailable.
I would recommend "e" model rather than "e2", if appropreate paper pipe is available.

Note that opening for TR130e2 in the drawing is indicated for Feastrex's NF5Exciter. It is unique.
Opening hole must be designed for specified driver unit to be used.
Rear hole in TR130e2 is for exciter wiring terminal.
It is used for exciter driver only.
Refer to Wide-Range Loudspeaker System with 5" Full-Range Drivers for more information.

TR130b - Pretty old, but good performance model

This is the first 5" model.
Recommended driver is Tangband's W5-1611SA.
Feastrex's NF5Exciter showed good match with this enclosure model.
My American friend gave me information that he made this model wit Fostex's FE138ES-R.
He was surprized at the performance of the system.
This is not easy model to assemble. TR130e model is easier to assemble, but some may prefer this TR130b.
Thickness of plates may be changed.

TR130b Internal Structure
TR130b Assembly
TR130b Cutting Plan(1)
TR130b Cutting Plan (2) for Fostex Driver

Terms & Conditions to Use MCAP-CR

MCAP-CR is patented by Japan Patent Office (patent# 5083703).
You may not use MCAP-CR for commercial purpose without contract, while you are allowed to make MCAP-CR applications for evaluation puropse.
This is personal small laboratory. Any kind of financial assistance is appreciated.
Use "Send Message" option in the top-left menu to contact me. Have good business with me

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