Tag Archive for Horn Speaker

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

 

 

 

 

 

 

 

 

 

 

 

 

JBL Everest DD66000 Bi-Amped with Accuphase

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Looking through some of my pictures, I remember a setup i really liked and i thought i should share it.

JBL DD66000 running bi-amped with Accuphase P-6100 driving Mid-High Drivers and M-6000 driving Low Drivers. This was presented when DF-55 crossover unit was introduced.

Hope you will enjoy the pictures.

JBL Everest  and Accuphase Bi-Amp Setup

JBL Everest and Accuphase Bi-Amp Setup

JBL Everest DD66000

JBL Everest DD66000

JBL Everest DD66000 also Avalon

JBL Everest DD66000 also Avalon

JBL Everest DD66000 2WAY

JBL Everest DD66000 2WAY

The Mighty Accuphase M-6000

The Mighty Accuphase M-6000

 

Thank you for visiting.

 

 

Electric Equivalent Model of Loudspeakers スピーカーの電気モデル

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Hello again,

In this article i will present a way to model the impedance of a speaker driver and how to use that in crossover design. Most crossover calculators on the internet assume a linear fixed impedance as the load of the filter but as you will see this is not the case. For this purpose I created a spreadsheet that will calculate the parameters for you.

The spreadsheet uses Electrical and Mechanical parameters of the loudspeaker driver and calculates the equivalent electrical component value to be used with any circuit simulation software (e.q. SPICE).

Re and Le are electrical components and describe the voice coil properties. Lces, Cmes and Res are mechanical components that are shifted via the BL coupling factor to the electrical side of the impedance model.

It is important to take this fact into consideration because more often than not the mechanical part of the impedance has an influence on the way the filter will respond.

In the below example you can see a standard L-R lowpass filter with a corner frequency of 1kHz. You can see the filter applied to a 8 ohm resistor in the way the most online calculators are being used and you can also see the filter applied to a complex load which represents the electrical model of the loudspeaker (without a box).

2nd order LR 1khz LPFNow lets look at the filters response ( dashed line represent the 8 ohm resistor load and the solid line represents the advanced electrical model load )

Compare Response of load on low pass filter

As you can see the differences cannot be negligible. Below you can find the attached spreadsheet that you can use to build the model. Also it can calculate the box influence for a closed box or bass reflex. The tree elements are connected in series and form  a branch that is connected in parallel to the mechanical equivalent components.

Electric Model of Loudspeakers

 

 

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。

ESOTERICの製品内部 – P-02 – D-02 – I-03

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P-02 SACD/ CD Transport

Esoteric P-02 SACD Transport

Esoteric P-02 SACD Transport

Esoteric P-02 SACD Transport

Esoteric P-02 SACD Transport: Top Side

Esoteric P-02 SACD Transport

Esoteric P-02 SACD Transport: Bottom Side

Esoteric P-02 SACD Transport

Esoteric P-02 SACD Transport: Mechanics

D-02 Digital To Analog Decoder

D-02 Digital To Analog Decoder

D-02 Digital To Analog Decoder

D-02 Digital To Analog Decoder

D-02 Digital To Analog Decoder: Bottom Side

D-02 Digital To Analog Decoder

D-02 Digital To Analog Decoder: Top Side

I-03 Integrated Amplifier

I-03 Integrated Amplifier

I-03 Integrated Amplifier

I-03 Integrated Amplifier

I-03 Integrated Amplifier: Top Side

Thank you for visiting,

ご覧いただきありがとうございます。

DENON AVC-A1HD内部 / Inside DENON AVC-A1HD

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こんにちは、

DENON AVC-A1HDの写真。

dsc02160 dsc02159

dsc02161

Thank you for visiting,

ご覧いただきありがとうございます。

Paper Tweeter

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I had a little fun Sunday night while listening to Elvin Jones. Found a pair of small paper tweeters, seemed of german made, probably Grundig, i think used in higher quality TV sets.

I hooked them up via a 3.8uF capacitor and listened a bit. While not the most revealing sound i like their timbre and thought they are good for jazz. I measured their respomse and impedance and then hooked them to a pair of OB speakers i have with a single russian fullrange driver. Very old drivers but got them in great condition.

There sure is something about light paper pulp cones that i like alot. Is it transients, dynamics or sensitivity i dont know for sure but my guess the secret is somewhere along those lines.

Paper Tweeter

Paper Tweeter

Paper Tweeter

Paper Tweeter

Paper Tweeter

Paper Tweeter

You can see response starts falling with increasing frequency. This is a much disputed issue with audio enthusiasts. Some prefer it like this (me as well) some like it flatter some prefer a bit on the rise. Either way you can see the tweeter with a 40mm diameter radiating cone can hold up to almost 60 degree dispertion within 6dB. Pretty impressive and pretty linear power response.

I hooked it to the fullrange system with a 2.2uF MKP capacitor.

Thanks for visiting.

DALI Epicon6スピーカー

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DALI成分の写真。 小さなTHD磁気回路を見ることができます。

Components of DALI Epicon 6 loudspeaker. You can see the low distortion magnetic circuit.

Dali Epicon 6 スピーカー

dsc02167 dsc02168 dsc02169

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