Archive for High Efficiency Multi Way

Project Harbinger: High Efficiency Loudspeaker System 高効率スピーカーシステム Part 2

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Hello,

こんにちは,

To continue with Harbinger project i would like to investigate the drivers and what could be expected from them. I already mentioned two of the 15 inchers and that i decided to use a version of 8512F.

The motor on this driver is very strong 220mm in diameter, noiseless vent and T-shaped central pole piece for symmetric field in gap as seen below.

 

T-shaped pole piece Loudspeaker

T-shaped pole piece 8512F

 

The original had this set of parameters:

Mms: 144 g
Fs: 41.9 Hz
Cms: 0.1 mm/N
Bl: 26 Tm
Rms: 12.8 mech-ohm
SD: 0.09 m2

This results in the following equivalent electrical components:

Lces: 67.6 mH
Cmes: 213.017751 uF
Res: 52.8125 ohm

Lces -> corresponds to Cms; Cmes -> corresponds to Mms; Res -> corresponds to Rms

First modification was changing the suspension system with a more softer one. The new spider has larger deeper and fewer corrugations. I made this modification so that the woofer can perform better at lower input power.

Spider for 4" Voice Coil 15インチスピーカー、DIYのホーンスピーカー

Original spider of the 15 incher

Spider for 4" Voice Coil 15インチスピーカー、DIYのホーンスピーカー

New spider for the 15 incher

The replacement spider i used before for a 10 inch driver modification to fit in a 4″ voice coil.

At this point i needed to build a new box to put in the woofer and study it’s behavior. I built a 160 Liters vented box with 2 ports each of 72mm diameter and 140mm length.

High efficiency Loudspeaker Enclosure

High efficiency Loudspeaker Enclosure

High efficiency Loudspeaker Enclosure

High efficiency Loudspeaker Enclosure

High efficiency Loudspeaker Enclosure

High efficiency Loudspeaker Enclosure

After placing the driver in the box i ran impedance test and simulation of the model created with the spreadsheet from Electric Equivalent Model of Loudspeakers article. As you can see the model is very close to the measured result.

Spice simulation of loudspeaker equivalent model with LPF

Spice simulation of loudspeaker equivalent model with LPF

Measured impedance of 15 incher with LPF

Measured impedance of 15 incher with LPF

The box wasn’t well braced and needed some strengthening but the output in the bass region was satisfactory. Even at low levels the bass was low with a good amount of punch. My room helps a lot though on the low end. I have wooden floors and ceiling and lots of furniture.

In the next article we will look at what else can be improved on the drivers and the box.

Thank you for visiting,

ご覧いただきありがとうございます。

 

New Paper Cones For Ryu Field Coil Loudspeaker

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Hello, こんにちは

私の日本語があまり上手くありませんが許して下さい.

Work on Project Ryu continues with a new model. This one will be a mid-bass by design but as always i will try to push the limits in bandwidth and sensitivity. The new cones are a bit on the heavy side weighting 18 grams but i think it will balance out very well in the mass controlled region.

プロジェクトの作業は、新しいモデルを継続します。このモデルは、MID_BASSスピーカーとなります、しかし、私は、SENSITIVITYとBANDWIDTHを高めるためにしようとします。フィールド·コイル·モータは、18グラムのスピーカーコーンとのバランスになります。

12 inch Cone for Ryu Field Coil Loudspeakers

12 inch Cone for Ryu Field Coil Loudspeakers

The 12 inch cone has a curved profile and concentric rings to reduce breakup effects.

12 inch Cone for Ryu Field Coil Loudspeakers

 

12 inch Cone for Ryu Field Coil Loudspeakers

 

Voice coil was designed using my Excel spreadsheet tool. You can find a link to download it at the end of the article. Double coil, each with estimated 8 ohm impedance allowing for 4-8-16 ohm operation.

私は私のExcelのスプレッドシートツールでボイスコイルを作りました。あなたは、記事の最後にそれをダウンロードするためのリンクを見つけることができます。ボイスコイルは、4または8または16オームとして使用することができます。

12 inch Cone for Ryu Field Coil Loudspeakers プロジェクト龍のフィールドコイルスピーカーのための12インチのコーン

 

voice coil design tool

 

You can download the spreadsheet here:

Voice Coil

Thank you for visiting,

ご覧いただきありがとうございます。

Modern JBL Loudspeaker Lineup

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Here are some pictures of loudspeakers currently in JBL offer preserving the old monitors look.

JBL 4306 Loudspeaker

JBL 4306 Loudspeaker

JBL STUDIO Series

JBL STUDIO Series

JBL SAS101

JBL SAS101

JBL S4700

JBL S4700

JBL STUDIO 590CH

JBL STUDIO 590CH

JBL S4700 Grill off

JBL S4700 Grill off

JBL S4700 Grill off

JBL S4700 Grill off

JBL 4365

JBL 4365

From Left to Right: JBL 4365 JBL 4429 JBL 4306 JBL 4319 JBL 4312E

From Left to Right:
JBL 4365
JBL 4429
JBL 4306
JBL 4319
JBL 4312E

JBL 4319 JBL 4312E

JBL 4319
JBL 4312E

JBL 4365

JBL 4365 and JBL Everest DD66000

JBL K2 S9900 and a Pair of JBL S4700

JBL K2 S9900 and a Pair of JBL S4700

 

Thanks for visiting

 

 

 

 

 

 

 

 

 

 

 

 

Project Harbinger: High Efficiency Loudspeaker System 高効率スピーカーシステム Part 1

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Hello, こんにちは

私にとって、ライブ感のある音にするには、素晴らしい強弱と高感度、大きな放射エリアが必要であると考えます。私のプロジェクトはそういった局面から始まり、今ではそれらが大きく効率に関わっていることが理解できます。

効率は音の比率で、音響効果では配信される音響のパワー対電気消費力です。このパラメーターがいかに重要であるかについては議論はあります。(多くのメーカーは公表していませんが。)というのも、多くのオーディオアンプは電源としてではなく電圧源として設計されているためです。スピーカーの電気抵抗は振動によって変化するので、アンプから引き出される電力が振動によって変化すると言うことができます。

ホーンは最も効率的な音響再生システムであるが、受動部品であるため低周波数で非常に大きくなります。サイズと複雑性のため、多くのシステムは低周波数と中·高周波数のためのロードホーンのためのダイレクトラジエーターを使って設計されています。しかし、ダイレクトラジエーターは十分な効率を作ることができるでしょうか。

それは実にコンポーネントによって異なります。高効率のために大きなモーター(強い磁束)が必要となります。光移動アセンブリ(ライトコーンとボイスコイル)、そして放射面積(大錐径)も必要になります。ダイレクトラジエーターからの良い低音は、少なくとも12インチのコーンを必要とすると考えています。家庭用としては、私は15インチのコーンが好きで、長年にわたってその価値を証明したこの直径の多くの素晴らしいドライバーがあります。

For me, to reach a live like sound it means i need great dynamics, high sensitivity and big radiation area. Many of my projects start with these aspects in mind and it is clear now that all these are related to efficiency.

Efficiency is a power ratio and in acoustics it is acoustic power delivered vs electric power consumed. There is some debate on how important this parameter is (many manufacturers don’t even publish it), because most audio amplifiers are designed as voltage sources and not power sources. Since impedance of a loudspeaker varies with frequency we can say that the power drawn from the amplifier will vary with frequency.

In the below simulation you can see this variation.

Impedance curve of woofer model

Modeled impedance curve of high efficiency woofer

 

Calculated input power with constant voltage source having the above impedance as load

Calculated input power with constant voltage source having the above impedance as load

 

You can easily see how power drawn in the low frequencies drops pretty much this causes sensitivity to drop but not because of low efficiency in the low register but because of how amplifiers are made.

A very important aspect i found to be true is to use high power amplifiers with high efficiency loudspeakers. These amplifiers will most likely have their output stages powered by high voltage and this allows for high voltage swings necessary when driving the high impedance at high levels.

Horns are by far the most efficient sound reproduction systems but since they are passive components they get very large at low frequencies. Because of size and complexity a large number of systems were designed using a direct radiator for low frequencies and horn loading for medium and high frequencies. But can a direct radiator reach a good enough efficiency?

It really depends on its components. For high efficiency you will need a big motor (strong magnetic flux), you will need a light moving assembly (light cones and voice coil) and you will need a big radiating area (large cone diameter).

It is my belief that for good bass from direct radiators one needs at least a 12 inch cone. For domestic use i like the 15 inch cone and there are many great drivers at this diameter that have proven their worth over the years.

At these diameters most drivers one can find come from the professional audio sector. There are many very good designs on the market, it can be hard to find something that can totally please me but given the fact that i like to modify the drivers a new project begun.

First thoughts were to make a standard 2 way system using the 500Hz sectoral horns i had in stock. For this purpose i build a couple of test boxes but first i will introduce the drivers.

First 15 incher was 6523C having a 3 inch voice coil and while the motor provided a good flux density in the gap, the thickness of the top plate was about 10mm. Not the thinnest but the greatest either. The structure is very simple with straight poles and no faraday rings. On the mechanical side again it revealed this was not a woofer for this project for the filter needed alot of optimization to make it work good with a xover point around 1kHz.

Here is the impedance model for this woofer:

Impedance model for 15 inch wooferhttp://www.hipowerpro.com/lbpdf/L15-6523C.pdf

High efficiency 2 way horn loudspeakerHigh efficiency 2 way horn loudspeaker

The second 15 incher is based on the 8512F which i modified in various ways. Originally this woofer is designed compact bandpass pro applications, the suspension system is pretty stiff and it needs alot of power to get it moving. So first i changed its spider and outer suspension.

15 incher high efficiency woofer

15 incher high efficiency woofer

 

15 incher high efficiency woofer

 

The unit has a tremendous motor designed to match JBL 2226H with a 220mm ceramic magnet ring and 12mm thick top plate. A 4 inch voice coil, a T shaped pole piece makes this 15 incher a real beast.

High efficiency 15 inch woofer

The first compression driver tested was a 1″ exit with Ti diaphragm and Ti suspension. I later replaced the suspension with mylar one. I had a sheet of mylar and cut out a ring to form the suspension. This improved on the transition region between the woofer and the CD as i will later show.

compression driver diaphragm

Compression driver mylar suspension

15 incher and enclosure model

Phase plug is after the old Tannoy Monitor Gold and should provide a better low frequency response.

Below you can see the model for the 15 incher and the bass reflex box. The box is tuned lower as the xover will bring the second peak down a bit.


15woofermodel

simulated impedance

Here are some of the first ideas for the enclosure:

2 way horn high efficiency loudspeaker

2 way horn high efficiency loudspeaker

I will end here the first article and will continue soon.

Thank you for visiting,

ご覧いただきありがとうございます。

ミッドレンジホルン型ラウドスピーカー / Midrange Front Loaded Horns Continued

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以前も述べたように、ホルンスピーカーから流れるあの力強いサウンドが好きで、ミッドバスシステムも発表しました。制作の流れや反響振動の測定値、ALTEC 511Bホルンクローンや3インチ圧縮ドライバーは後日アップします。

In previous article i mentioned i like the powerfull sound from horn loudspeakers and presented a mid-bass horn system. I will continue showing how it was built and show frequency response measurements and how i integrated the ALTEC 511B horn clone and 3 inch compression driver.

The 10 incher driver i used was a 6366 i worked on with HiPower. Other 10 inch drivers that can be used:

RCF L10-568

Precision Devices PDN.10MH25

Faital Pro 10PR310

The mid bass construction is made of MDF of 20mm thickness and 8mm thickness. Below you can see some pictures with the construction:

Mid bass horn dual 10 inch Mid bass horn dual 10 inch Mid bass horn dual 10 inch Mid bass horn dual 10 inch Mid bass horn dual 10 inch Mid bass horn dual 10 inch

The main problem with front horns loading cone drivers is high frequency response. Especially if the cone is large in diameter. You can have a strong motor, a very light cone, and a low inductance and still have a poor high frequency response. That is because of the air trapped between the cone and the horn throat.

This is similar to compression chamber in high frequency compression drivers. What happens is that at low frequencies all the air is pushed to the horn through so air behaves like a mass, similar to the air in a bass reflex port. At high frequency however not all the air from that volume gets into the throat. At some point is starts to be compressed and thus it acts like a compliance. This is a basic acoustic low pass filter and it’s the main culprit for high frequency response roll off.

Compliance of air at horn throat

This is very important when front loading a fullrange driver. You can only use minimal compression ratio so that most of the radiating surface of the driver is in the horn throat.

Observing this i constructed a 10 inch driver with a 4 inch voice coil so that the cone has a flatter profile and be closer to the horn throat.Took some experimenting but i went for a softer suspension and a high BL of 24Tm. Below you can check some pictures:

DIY 10 inch Horn Cone Driver DIY 10 inch Horn Cone Driver DIY 10 inch Horn Cone Driver DIY 10 inch Horn Cone Driver DIY 10 inch Horn Cone Driver DIY 10 inch Horn Cone Driver

High Frequency response did increase and the driver had tremendous force but unfortunately i built just one. Not only high frequency improved but the overall sensitivity improved due to the stronger motor. The diameter of the magnet ring is 200mm and the system had a Qts of 0.14!

Below you can see two on axis frequency response curves for the horn using 2 6366 10 inch units. The black trace shows response with the back wall installed and the blue one is with the back chamber left open.

Frequency Response of mid-bass horn

For high frequency i used a large format compression driver with a 3 inch diaphragm made from titanium and mylar surround. The driver can go to 700Hz fairly easily and has a pretty good high frequency response. It is based on 8074 from Hipower but modified the design for mylar surround and different phaseplug.

3 inch compression driver

3 inch compression driver and ALTEC 511 Clone Horn  コンプレッションドライバーとALTEC511ホーン

I used an active crossover to setup the system, using a first order filter at 3kHz managed to get an acoustic xover point around 700Hz. Horn cut at 600Hz 12db/octave. Here is the on axis system response:

Front loaded Horn frequency response

I also tested Peavey RX-22 and RCF ND650 and winner would be the RCF driver having better top end.

As this is an old project of mine i am still trying to find the detailed schematic of the horn through my files. I will do another followup once i find them.

Thank you for visiting.

ご覧いただきありがとうございます。

ミッドレンジホルン型ラウドスピーカー / Midrange Front Loaded Horns

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Hello / こんにちは,

I like very much the sound of front loaded horns. They have very good dynamics and the impact that i associate with live sound. I had quite a few experiences with front loaded horns which i will be presenting on this blog.

In the video above you can see a 2 way FLH system composed of a mid-bass horn with dual 10 inchers and a 500Hz horn clone of Altec 511B loading a 3 inch compression driver.

I made this horn because i felt there is not enough impact from direct radiators in the midrange. A driver that can be crossed low can be pretty expensive although i have been looking at Monacor KU-516 or Klipsch K55 which are reasonably priced.

A basic sketch of the mid-bass horn is shown below. It is a conical horn loading the front of the drivers and a bass reflex enclosure loading the back of the drivers.

horn 2x10

You can find below the Akabak script that describes this horn system:

|FLH 210 Mid-bass

Def_Driver ‘6366’
dD1=8cm dD=23.2cm tD1=4.8cm
Mms=34.9g Cms=0.19mm/N Rms=.15mks
Re=5.3ohm BL=13.8Tm Le=0.95mH

System ‘Mid-Bass Horn’

Driver Def=’6366′ ‘D1′ Node=0=1=10=20
Driver Def=’6366′ ‘D2′ Node=0=1=30=40

|Front Wave

Duct ‘FrontChamber1′ Node=10=11
dD=23.2cm Len=2cm
Duct ‘FrontChamber2′ Node=30=12
dD=23.2cm Len=2cm
AcouMass ‘Entry1′ Node=11=13
Ma={ (1.2/(3.14*0.1))*(sqr(0.26-0.23)/(2*0.26*0.23))*ln((0.26+0.23)/(0.26-0.23))+ln(sqr(0.26+0.23)/(4*0.26*0.23))}
Horn ‘FrontHorn1′ Node=13=14
Conical
WTh=10cm HTh=26cm
WMo=54cm HMo=34.5cm
Len=30cm
x=0 y=17.5cm z=0 HAngle=0 VAngle=0
AcouMass ‘Entry2′ Node=12=15
Ma={ (1.2/(3.14*0.1))*(sqr(0.26-0.23)/(2*0.26*0.23))*ln((0.26+0.23)/(0.26-0.23))+ln(sqr(0.26+0.23)/(4*0.26*0.23))}
Horn ‘FrontHorn2′ Node=15=16
Conical
WTh=10cm HTh=26cm
WMo=54cm HMo=34.5cm
Len=30cm
x=0 y=-17.5cm z=0 HAngle=0 VAngle=0

|Back Wave

Duct ‘D_rear1′ Node=20
WD=26.5cm HD=21cm Len=32cm
Duct ‘D_rear2′ Node=20=40
WD=26.5cm HD=27cm Len=32cm
Duct ‘D_rear3′ Node=40=41
WD=26.5cm HD=21cm Len=32cm
|AcouMass ‘Entry1′ Node=41=50
|Ma={ (1.2/(3.14*0.1))*(sqr(0.12-0.04)/(2*0.12*0.04))*ln((0.12+0.04)/(0.12-0.04))+ln(sqr(0.04+0.12)/(4*0.04*0.12))}
Waveguide ‘D_rear4′ Node=41=42
WTh=16.5cm HTh=4cm Len=35cm
WMo=27cm HMo=4cm
Radiator ‘R1′ Node=42
WD=27cm HD=4cm
x=-14.5cm Y=-30.4cm z=0
Waveguide ‘D_rear5′ Node=41=43
WTh=16.5cm HTh=4cm Len=35cm
WMo=27cm HMo=4cm
Radiator ‘R2′ Node=43
WD=27cm HD=4cm
x=14.5cm Y=-30.4cm z=0

You can remove “|” from:

|AcouMass ‘Entry1′ Node=41=50
|Ma={ (1.2/(3.14*0.1))*(sqr(0.12-0.04)/(2*0.12*0.04))*ln((0.12+0.04)/(0.12-0.04))+ln(sqr(0.04+0.12)/(4*0.04*0.12))}

and modify nodes 41 with 50 on D_rear4 and D_rear5 to consider acoustic mass at the port entrance caused by the 90 degrees bend. Also you can model any other 10 inch driver by defining its parameters.

Running the sims you can see results below. 90 degree directivity point is at 700Hz somewhat lower than i expected and that meant i need to cross the high frequency horn below 1kHz.

Front loaded horn polar response

Front loaded horn polar response

Front loaded horn frequency response

Front loaded horn frequency response

Frequency response is optimistic on high frequency but we will see how it turns out in next article.

 

Thank you for visiting.

ご覧いただきありがとうございます。

ホーンプロファイル研究 / Horn Profile Study

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Presented here is the way to design and build a quadrant
horn. This horn was born from the need of a simple to build contour. An
exponential or hypex contour can pose problems for an amateur builder
having access just to handheld tools. The quadrant horn can be easily
constructed with the use of a hand operated router.

ここで展示されているのは、Quadrant ホーンの設計と構築の方法です。このホーンは、音調曲線を作るというシンプルな必要性から生まれました。急上昇またはhypexな音調曲線は、小型ツールへのアクセスを持つアマチュア製作者にとっては問題になることがあります。四分円ホーンは、手操作ルーターの使用で簡単に組み立てることができます。

1. The contour calculation:
The horn contour describes an arc of a circle equal in length with
the circumference of a quadrant. Looking at a cross-section along the x
axis we can see that each side defines the outline of a quadrant. The
circles have their centers on the same plane with the horn’s throat so x
coordinate of the center will always be 0.
In practice it can differ as other segments can be added between
the throat and the driver to provide a better loading of the diaphragm.
In order to plot the curve we will look at the fourth quadrant of a
circle. Starting from the circle equation: (x-a)^2+(y-b)^2=R^2. With
(a,b) being the coordinates of the circle’s center and as we stated a=0
then our equation will be x^2+(y-b)^2=R^2.
The reason we chose a=0 is that x will be the axis of expansion for
our curve. This means that for each value of x>=a we will calculate the
value of y and plot the (x,y) point.
Fig. 1. shows a drawing of the horn’s contour. It is important to
notice that the value of b will be calculated knowing the radius of the
throat and either the radius of the circle or the radius of the mouth.
The radius of the mouth can be chosen to meet a desired system’s
dimensions or from the common term in the PA world “mouth frequency” or
the horn’s cutoff frequency.
In fig. 1. we can see that b=Rt+Rc, with Rt= throat radius, Rc=
circle radius. The mouth radius will always equal the value of b,
Rm=Rt+Rc.
Our equation now becomes x^2+(y-Rt-Rc)^2=Rc^2. To determine the
values of y for the fourth quadrant we are interested in the negative
solutions for x=0…Rc. It is important to notice that the value of x
can never exceed the value of Rc.
To plot the curve in positive x,y coordinates the equation is:
y=(Rt+Rc)-sqrt(Rc^2-x^2)
The values of y(x) with x=0…Rc describe just the radius at
distance x of an axisymmetric horn. To determine the diameter or width
we just need to multiply by 2:
D(x)=2*[(Rt+Rc)-sqrt(Rc^2-x^2)]

Horn profile calculation

Fig. 1.

 2. Modeling
A spreadsheet was developed for calculation of Baffle input
parameters for AxiDriver based on the last equation.
There are some observations that can be easily made looking at
fig.1. As it is, the horn will always have the mouth diameter more than
2 times the length of the horn. This rapid expansion makes it more
suitable for midrange and high frequency usage.
In the next pages are the results of AxiDriver simulations of
different sizes of Rm for the quadrant horn.

110 130 150 170 190 210 230 250 270 290 310 330 350

As can be seen from BEM simulations, the profile maintains a nice 60 degree directivity all the way to 20kHz.

Attached you can find the spreadsheet to run your own simulations.

quadrant horn spreadsheet

Thank you for visiting / ご覧いただきありがとうございます。

TANNOY KINGDOM ROYALスピーカー

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こんにちは、ここでは、TANNOY KINGDOM ROYALのいくつかの写真です。私はEsotericアンプで聞きましたが、格別な演奏を楽しむことができました。

Tannoy Kingdom Royal Components view

Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view Tannoy Kingdom Royal Components view

ご覧いただきありがとうございます。

同軸TQWTスピーカープロジェクト/Coaxial TQWT Loudspeaker Project

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This is an old TQWT Loudspeaker project on which i still have some data saved and i thought i should present it.

One of the other drivers from HiPower Audio Co. was 6366 a very nice 10″ mid-bass with quite a smooth frequency response and low distortion. With a high resonance frequency though they were shy on bass in a bass reflex enclosure though so for home hi-fi systems other alignments needed to be considered.

A FLH horn was considered due to the strong motor and the stiff suspension system but with a Mms of 34.9g is not really light enough for this kind of application. So the next thing that came to mind was a TQWT Loudspeaker.

I had built other TQWT/VTP  loudspeakers and i usually have the mouth area between 0.5 and 1.5 of SD of the driver. This however requires a strong motor on the driver to control it.

Here are specs for 6366:

  • Nominal Diameter: 250mm/10inch
  • Power Handling: 180W
  • SPL: 95dB/W/m
  • Minimum Impedance: 6.1 ohm
  • Re: 5.3 ohms BL: 13.8 Tm Le: 0.95mH
  • Mms: 34.9g Cms: 0.19mm/N Re: 1.15 mecks
  • Fs: 61Hz Vas: 32.2L SD: 350cm^2
  • Qes: 0.38 Qms: 11.8 Qts: 0.37
  • Efficiency: 1.95%

Similar mid-bass that will work well is Monacor SP-10/150PA

Below you can find the drawings of the enclosure as well as acoustic fill material placement along the line.

同軸TQWTスピーカープロジェクト TQWT Loudspeaker同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker

The acoustic fill material inside the enclosure was chosen to be mineral wool. It has a very good price/quality ratio. Several tests were performed before choosing the best positioning.

Thinking of the high frequency unit, the mid-woofer had a vent of 30mm diameter and i realized i that could be the acoustic path for a compression driver mounted on the back of the woofer. This way i could create a coaxial driver with its coherence advantages.

I create a simple aluminum tube to transition smootly from 25mm to 30mm. Once it exit  the mid-bass pole piece it needed a small horn, otherwise it would beam very much and there are many changes to get high amounts of doppler distortion.

I have found a pair of small Bi-radial like horns that seems perfect for the job. Running a test in AxiDriver demo shows a pretty good directivity control up until 12-13Khz, after that it start lobbing.

同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT LoudspeakerCrossover starter from my old first order at around 20kHz for the compression driver. This allows the elimination of an L-pad with i don’t like to use very much. Allowing a slow slope 6db/octave evens out the rise in the lower frequency that horns give to compression drivers so not only you will match sensitivity to that of the woofer without L-pad but you also reach a linear frequency response.

同軸TQWTスピーカープロジェクト TQWT Loudspeaker

Axial frequency response of mid-bass

同軸TQWTスピーカープロジェクト TQWT Loudspeaker同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT LoudspeakerFirst crossover version and frequency response.

同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker同軸TQWTスピーカープロジェクト TQWT Loudspeaker

 Second crossover schematic, response and electrical impedance

同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker 同軸TQWTスピーカープロジェクト TQWT Loudspeaker

First test was done on my RH84 amplifier. High resolution, good tonal balance and the best stereo image i ever got. The coaxial experiment resulted in a nice coherent source. All sounds come from the same center, the speakers just disappear completly. With the russian 6P3S-E PP amp the fullness and power started to show. Its a very dynamic speaker and can deliver really high output. It is amazing how much bass you can get from a woofer with a resonance frequency of 63Hz if used in a TQWT loudspeaker and properly loaded.

JBL EVEREST内部 / Inside JBL EVEREST DD66000

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バスレフ・ポートは、低いひずみと圧縮を最適化します。

Bass reflex port seems to be optimized for low distortion and compression.
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JBL EVERESTは、高性能スピーカーシステムです。私はAccuphaseアンプやマークレビンソンアンプで聞きましたが、格別な演奏を楽しむことができました。個人的にはAccuphaseの方が好きでしたが、同じセットアップ上ではAvalon timeよりは良い響きだったと思います。ダイナミックなインパクトと高解像度のフルサウンドを同時に。

 

JBL EVEREST is a high fidelity loudspeaker system. I enjoyed exceptional performance with Accuphase amp and Mark Levinson amp. I liked it more with ACCUPHASE and to me it sounded better than AVALON TIME on the same setup.Full sound with great impact and high resolution at the same time.