Just follow FM , Cello to biuld a analog EQ Linearizer

[asterkao]

ToyX project EQ Linearizer study case1 ...define band center frequency

I decide to DIY EQ Linearizer call X project.
Because this step is ultimate diy in the end to tuning sound color from 10Hz to 20kHz.

I had ever take a tube to be a EQ before but phase shift issue cause signal wave distortion and not time shift only.

Simulate the band filter for correct phase shift issue first.
Just follow FM , Cello do band sepration and do some center frequency modify.
After estimate I Define The 5 band pass filter the C-Freq. will be 50Hz,250Hz,1KHz,4KHz,12.8KHz.

images-1.jpg
Center Frq. 50Hz of band1.
Band1: 5~100Hz (5 pcs 20hz band pass filter inside 5~20,20~40,,80~100hz)
Right Axis Center phase is degree 0 ,Left -Pi is -180 phase degree & Right +Pi is +180 phase degree @1 db band-width.

images-2.jpg
Coding a program to caculate help estimate for use big Cap. or Inductor to do L-Cfilter.

images-3.jpg
Center Frq. 250Hz of band2.
Band2: 100~400Hz (5 pcs 60hz band pass filter inside 100~160,160~220,,340~400hz)
Right Axis Center phase is degree 0 ,Left -Pi is -180 phase degree & Right +Pi is +180 phase degree @1 db band-width.

images-4.jpg
Center Frq. 1KHz of band3.
Band3: 400~1600KHz (5 pcs 240hz band pass filter inside 400~640,640~880,,1360~1600Hz..)
Right Axis Center phase is degree 0 ,Left -Pi is -180 phase degree & Right +Pi is +180 phase degree @1 db band-width.

images-5.jpg
Center Frq. 4KHz of band4.
Band4: 1.6K~6.4KHz (5 pcs 1Khz band pass filter inside 1.6K~2.56K,2.56k~3.56k,,5.4K~6.4KHz)
Right Axis Center phase is degree 0 ,Left -Pi is -180 phase degree & Right +Pi is +180 phase degree @1 db band-width.

images-6.jpg
Center Frq. 12.8KHz of band5.
Band5: 6.4~19.2KHz(5 pcs 2.56K band pass filter inside 6.4K~ 9.86K,9.86k~11.52K,,16.64k~19.2Kband...)
Right Axis Center phase is degree 0 ,Left -Pi is -180 phase degree & Right +Pi is +180 phase degree @1 db band-width.

Mr211's Blog
http://tw.myblog.yahoo.com/jw!9frLFy...oZT_geG5fC24WQ--

[asterkao]

Oder transformer...
34.67H / 10mA x2 pcs
10.26H/10mA x4 pcs
2.9H/10mA x 2pcs
9.65H/10mA x4 pcs
1.039H/10mA x2pcs
9.12H/10mA x12pcs
0.524H/10mA x2pcs
0.315H/10mA x2 pcs
0.471H/10mA x 2pcs
2.93H/10mA x20ps
0.695H/10mA x20pcs
Big transformer
images-7.jpg

Mr211's Blog
Mr211's Blog - Yahoo!?????

[asterkao]

ToyX project EQ Linearizer study case2


Images-1.jpg
Placment inductor of Band pass filter .


Images-2.jpg
prepare capacitor of band pass filter


Images-3.jpg
Do a rough structure placement.
So far just one channel audio EQ structure.


Mr211's Blog
Mr211's Blog - Yahoo!?????

[asterkao]

ToyX project EQ Linearizer study case3

images-8.jpg
Tuning each inductor value for meet LC band pass filter

images-9.jpg
Finish each band pass structure

images-10.jpg
Test each band the frequency of drift .


images-11.jpg
Side view picture.
Estimate EQ Linearizer outline (each channel ..two layer structure) and prepare drawing of EQ case.

Mr211's Blog
Mr211's Blog - Yahoo!?????

[asterkao]

ToyX project EQ Linearizer study case4

images-1.jpg
Hand make to Finish each band circuit by jump wire.

images-2.jpg
Finish EQ power connect circuit and do placement esitmate.

images-3.jpg
Test two bands EQ function together (by cascade).

images-4.jpg
Feed SG signal in band 4 for function test.

images-5.jpg
Measure output signal form band 5 and estimate circuit where need modify to meet design.

images-6.jpg
Band 4 top view.

images-7.jpg
Receive EQ box order from two month ago.
This is front view with ten volume knobs.
Each channel with five knobs to control EQ.

images-8.jpg
Inner picture.

images-9.jpg
Rear panel picture.

Mr211's blog
Mr211's Blog - Yahoo!?????

[asterkao]

ToyX project EQ Linearizer study case5
images-1.jpg
Put on L channel EQ module and check out the hole of screws

images-2.jpg
Assemble copper cylinder prepare for put on R chhanel EQ module.

images-3.jpg
Check out two channel EQ modules structure Meet design or not.

images-4.jpg
Another view.

images-5.jpg
Assemble Fuse,RCA connectors,Volume knob,power switch.


images-6.jpg
Finish wires jump between each band and volume knob.

images-7.jpg
Anothr view.

Mr211's Blog
http://tw.myblog.yahoo.com/jw!9frLFy...T_geG5fC24WQ--

[qusp]

wow thats some project, very impressive!!

not to be a downer, but could you not perform perfectly linear EQ function inside the box? I mean you are using a DAC as I have seen your dac project, so why not calculate EQ at 40-48 bit depth (or higher) inside waves diamond plugin with matching hardware acceleration? would be different if you were also seeking a cheap solution, or to colour the sound with distortion, but you arent.

suppose of course this would not be as DIY

[asterkao]

Originally Posted by qusp

wow thats some project, very impressive!!

not to be a downer, but could you not perform perfectly linear EQ function inside the box? I mean you are using a DAC as I have seen your dac project, so why not calculate EQ at 40-48 bit depth (or higher) inside waves diamond plugin with matching hardware acceleration? would be different if you were also seeking a cheap solution, or to colour the sound with distortion, but you arent.

suppose of course this would not be as DIY

Hi :
Your guess right this a personal DIY.
That's too many components in your audio gear system will effect sound feeling.
Base this reason I hope to make a system could easy tunning sound is system.
That's way I make a Analog EQ Linearizer.

Another reason I had ever listen one Pre-Amp (have DSP EQ inside) before.
sound feeling just loss 3D Sound field re-bulide become 2D feeling.
Loss so much detail.

I know DSP ability even 64bit...some time need do trad-off to design.
Special is the filter design easy cause the small signal and second harmonic easy to get loose.

My principle of audio gear just a 5Hz~20KHz total impedance match.
So analog EQ linearize could easy to tuning signal level in the system.
I beliving yr got exprince that's just chang a cable will chnage something in yr system.

That's why Cello have palette and FM have new 268 re-amplifier to execute this function.
Thay just re-bulid each record (curve of RIAA) form LP to CD.

My person concept for just your reference.

Aster
Mr211's Blog - Yahoo!?????

[asterkao]

ToyX project EQ Linearizer study case.....6

images-1.jpg

Finish analog EQ channel L connection and make each band test.

images-2.jpg

Left down coner is band 3 -1Khz,Right down coner is band 5 -12.8kHz.

images-3.jpg

Put on copper post for boost up analog EQ channel R module.

images-4.jpg

Lock screw for channel R module and finish wire jump.


images-5.jpg

Ten knobs look .....
How about... look familiar with someone?
So far this project take me about one year.
Just prepare into a phase of pre-test tunning sound color.

Aster
Mr211's Blog - Yahoo!?????