This PDF 1.7 document has been generated by Adobe InDesign CS5.5 (7.5.1) / Adobe PDF Library 9.9, and has been sent on pdf-archive.com on 23/10/2011 at 18:24, from IP address 188.142.x.x.
The current document download page has been viewed 5108 times.
File size: 2.84 MB (17 pages).
Privacy: public file
Modular EQ project with gyrators
3 -
Schematics and Bill of
Materials for simple EQ
circuits with gyrator filters
Simple gyrator and permanent Q active filter EQ project
Schematics and Bill of Materials for gyrator EQ project
Schematic and BOM of simple “5 band EQ”
1
2
3
5
6
+15V filt1
GND
12
11
10
9
8
7
6
5
4
3
2
1
P1
Header 6X2A
R1
3.3k
-15V filt1
4
A
GND
R3
C
10
10k
R4
U1B
TL074J
7
6
R2
B
5
2
A
3
U1A
TL074J C1
1
A
10u
3.3k
11
10u
1M
12
U1D
TL074J
14
3
R5
1.2k
R10
18k
GND
B
2
C4
C5
330n
330n
R11
18k
A
U2A
TL074J
1
6
5
R6
1.2k
C3
B
GND
U2B
TL074J
7
100n
9
GND
C7
C8
33n
33n
C
10
R7
1.2k
R12
18k
C6
100n
D
11
13
4
GND
U2C
TL074J
8
13
R8
1.2k
R13
18k
GND
C9
C10
10n
10n
D
12
U2D
TL074J
14
R9
1.2k
R14
18k
GND
C11
C12
3.3n
3.3n
B
H1
3
2
1
P2
P4
GND
3
2
-15V
50k
C13
100n
C15
330n
P3
P5
50k
50k
+15V
H3
Read details, updates, advices on the page of schematics and notes. PCB-s and more
notes, pictures, advices about this project are available on the author’s blog and websites:
U1C
TL074J
8
9
C2
This project made to create and try simple and noiseless EQ with circuit called “gyrator”. This method is very simple, easy to assemble, and good quality for home hi-fi
systems. You can find very simple 5 band EQ with this method, and modular EQ with
sub-circuits and mainboard for 10 and 5 band equalizer.
1
P6
50k
3
GND
C14
10n
C16
33n
2
50k
C17
3.3n
H2
1
English blog and PCB order: http://custompcb.blogspot.com/
Hungarian blog and PCB order: http://diyguitarpa.blogspot.com/
The Youtube Channel • Picasa gallery • Email: gitarfogas@gmail.com
3
2
U3B
GND
Schematics and Bill of Materials for simple EQ circuits with gyrator filters . . . . . . . . . . . . . . . 2
B
The power supply for all gyrator EQ projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Schematic and BOM of power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
The power supply PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Math expressions, articles for gyrator EQ designs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Articles and images about gyrator EQ projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Math expressions for gyrator design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
The frequency response of 10 channel modular EQ project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Previous PCBs and images for simple 5 band and permanent Q 10 band EQ . . . . . . . . . . . 26
The previous version of simple 5 band EQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
The previous version of RANE based permanent Q project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
9
1
A
R16
1.2k
C21
C18
330n
100n
GND
10
U3C
13
8
C
R22 TL074J
18k
R17
1.2k
GND
2
14
D
12
U4A
3
R18
1.2k
R23 TL074J
18k
C19
33n
U3D
A
R24 TL074J
18k
C22
10n
GND
GND
C
1
R19
1.2k
C20
3.3n
R25
3.3k
4
13
R27
10k
10u
D
12
R28
D
U4D
TL074J
14
9
R26
C
10
U4C
TL074J
8
6
5
B
U4B
TL074J C23
7
10u
3.3k
D
11
C24
GND
6
5
4
3
2
1
Top and bottom PCBs and overlay of simple 5 band EQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Top and bottom PCBs and overlay of stereo gyrator module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Top and bottom PCBs and overlay of 2 mono gyrator module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Top and bottom PCBs and overlay of power filters (ver.3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Top and bottom PCBs and overlay of power filters (ver.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Top and bottom PCBs and overlay of power filters (ver.1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
The mainboard of 10 band EQ for gyrators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
R21
18k
U3A
TL074J
+15V filt2
1M
P7
Header 6X2A
Title
12
11
10
9
8
7
Printed Circuit Boards for gyrator EQ project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3
R15
1.2k
R20 TL074J
18k
GND
3
4
5
6
2
7
11
6
C
4
1
H4
5
Schematic and BOM of simple “5 band EQ” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
One stereo gyrator filter module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The power filter module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10 channel gyrator EQ mainboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
GND
-15V filt2
http://custompcb.blogspot.com/
http://diyguitarpa.blogspot.com/
GND
1
2
Description
Value
5 band stereo gyrator EQ
Size
Footprint
3
Quantit
y
Designator
Date:
File:
Model:Footprint
10u
Cap, Tantal, 1mil
4 C1, C2, C23, C24
Capacitor
100n
RAD-0.3
4 C3, C6, C13, C18
Radial Cap, Thru-Hole; 2 Leads; 0.3 in Pin Spacing
Capacitor
330n
RAD-0.3
4 C4, C5, C15, C21
Radial Cap, Thru-Hole; 2 Leads; 0.3 in Pin Spacing
Capacitor
33n
CAP, WIMA, 2MIL
4 C7, C8, C16, C19
Capacitor
10n
CAP, WIMA, 2MIL
4 C9, C10, C14, C22
Capacitor
3.3n
CAP, WIMA, 2MIL
Panel Connector
3 input Small
4 C11, C12, C17, C20
2 P1, P7
4 H1, H2, H3, H4
Resistor
50k
HDR2X6_CEN
Pots Plastic
Stereo
Resistor
3.3k
AXIAL-0.4
4 R1, R2, R25, R26
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin Spacing
Resistor
10k
AXIAL-0.4
2 R3, R27
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin Spacing
Resistor
1M
AXIAL-0.4
Resistor
1.2k
AXIAL-0.4
Resistor
18k
AXIAL-0.4
Low-Noise JFET-Input Operational Amplifier
J014
Connector; Header; 6x2 Position
5 P2, P3, P4, P5, P6
2 R4, R28
R5, R6, R7, R8, R9,
R15, R16, R17, R18,
10 R19
R10, R11, R12, R13,
R14, R20, R21, R22,
10 R23, R24
4 U1, U2, U3, U4
Revision
10/17/2011
D:\!Works\..\5 band gyrator EQ.SchDoc
4
Polarized Capacitor (Radial)
Header, 6-Pin, Dual row
Number
A
5
Sheet of
Drawn By:
6
Notes
This the simplest schematic
of 5 band stereo gyrator EQ.
The PCB is small, potentiometers inserted to the board.
Cheap, low noise, good
quality for home hi-fi applications.
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin Spacing
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin Spacing
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin Spacing
DIP; 14 Leads; Row Spacing 7.62 mm; Pitch 2.54 mm
The band frequencies of this
board: 100Hz - 300Hz - 1kHz - 3kHz
- 10kHz.
Document last modified and saved: 23 October 2011 6:15 PM
- 4
Simple gyrator and permanent Q active filter EQ project
5 -
Schematics and Bill of Materials for gyrator EQ project
One stereo gyrator filter module
Simple gyrator and permanent Q active filter EQ project
Schematics and Bill of Materials for gyrator EQ project
The power filter module
Notes
This is the part of modular EQ project. This is the most important schematic: the gyrator. The gyrator is the
main filter for the equalizer. The band frequency depend on the value of capacitors “C(a)” on the schematic.
Because this is module only, another modules and mainboard required to complete the multiband EQ. Two
version of PCB-s available for this one module: one of them have stereo potentiometers to adjust both left
and right channel at one time. Another PCB separated to two mono channel with two mono potentiometers to adjust left and right channels independently. The first version is good for home hi-fi users, the second
is better for instrument amplifications. With the EQ mainboard, you can build this module for any frequencies,
set the Q and the boost/cut of the band. Look at the math expressions of this module to count the values of the
resistors and capacitors.
1
2
3
4
A
P1
1
2
3
4
5
6
B
GND
C1
47uF 60V
7
8
9
10
11
12
R1
BC560C
Q1
3
4
5
6
12K
C8
47nF
GND
GND
This schematic contains only one gyrator filter circuit. For this circuit required mainboard to complete 10 channel EQ. For the EQ
bands, C(a) capacitors have to be changed to several values. Visit the authors website for details.
A
http://custompcb.blogspot.com/
http://diyguitarpa.blogspot.com/
•
•
•
•
•
8
+15V
2
A
3
4
R2
18k
B
U1A
TL072P
1
•
R1
1.2k
C1
B
C2
C(a)
C(a)
GND
P1 L
6
C
5
B
P2
U1B
TL072P
7
C3
P1
1
2
3
4
5
6
P1 U
50k
P2 U
C(a)
R3
1.2k
R4
18k
P2 L
7
8
9
10
11
12
Header 6X2A
C4
C
GND
C(a)
GND
-15V
Title
Number
Revision
D
A
Date:
File:
1
2
Comment
Cap
3
Value
C(a)
Header 6X2A
10/17/2011
D:\!Works\..\1 stereo gyrator.SchDoc
Quantity
4
C3
C4
R3
R4
31
6.8µ
100n
470�
100k
63
3.3µ
47n
390�
100k
125
1.5µ
33n
390�
100k
250
680n
22n
330�
82k
500
330n
10n
330�
100k
1K
150n
4.7n
330�
100k
2K
100n
2.2n
330�
82k
4K
56n
1n
390�
82k
8K
22n
470p
390�
82k
16K
10n
220p
390�
100k
Sheet of
Drawn By:
5
Description
4 Capacitor
Hz
The values of R3 is same as R1, the
R2 is same as R4. Also look the math
expressions for another examples.
Stereo gyrator EQ module
Size
D
Polarized Capacitor (Radial)
Change all of the 50K adjustable resistors to 25K
6
Designator
C1, C2, C3, C4
Footprint
LibRef
CAP, 2 and 3 MIL
Cap
1 Header, 6-Pin, Dual row P1
HDR2X6_CEN
Header 6X2A
Pot stereo
50k
1 Resistor
P2
Pots Plastic Stereo
Pot stereo
Res2
1.2k
2 Resistor
R1, R3
AXIAL-0.4
Res2
Res2
18k
2 Resistor
R2, R4
AXIAL-0.4
Res2
dip-8
TL072P
TL072P
1 Low-Noise JFET-Input Operational
U1
Amplifier
Size
C7
B
GND
2
Value
47uF 60V
Date:
File:
3
Footprint
Elco 6mm, 1 mil
pins
Power filter module
Number
Revision
A
This schematic is the partof preamps and EQ projects. This module filtering the symmatrical (+-) power for
circuits. PCB and another modules, mainboards are available.
Description
For 10 band EQ:
12K
C6
47nF
47uF 60V
C
1
100Hz - 330n
300Hz - 100n
1kHz - 33n
3kHz - 10n
10kHz - 3.3n
BC550C
Q2
R2
Header 6X2A
For 5 band EQ:
A
GND
C2
100nF
C
D
Examples of C(a):
C4
10uF C5
10uF
C3
100nF
http://custompcb.blogspot.com/
http://diyguitarpa.blogspot.com/
2
6
A
Title
1
5
10/11/2011
D:\!Works\..\PowerFilter.SchDoc
4
Quantit
y
Sheet of
Drawn By:
5
Designator
6
Model:Footprint
2 C1, C7
Capacitor
100nF
RAD-0.3
2 C2, C3
Polarized Capacitor (Radial)
10uF
Cap, Tantal, 1mil
2 C4, C5
Capacitor
47nF
RAD-0.3
2 C6, C8
Capacitor; 2 Leads
HDR2X6_CEN
1 P1
Header, 6-Pin, Dual row
D
Capacitor; 2 Leads
Transistor PNP Silicon
BC560C
29-04
1 Q1
Transistor NPN Silicon
BC550C
29-04
1 Q2
Connector; Header; 6x2 Position
TO, Flat Index; 3 In-Line, Axial Leads; Body Dia.
4.8mm; Leads 0.48 x 0.5 mm (max)
TO, Flat Index; 3 In-Line, Axial Leads; Body Dia.
4.8mm; Leads 0.48 x 0.5 mm (max)
Resistor
12K
AXIAL-0.4
2 R1, R2
Resistor; 2 Leads
Notes
This module required for the EQ mainboard is the power filter circuit. I like to use this simple circuit
to filter the problems of power. These circuits have to be connected to the headers of mainboard.
These modules required for better power and less noise, but if you think this is not important, you
can wire pin 8 to pin 11 and pin 7 to pin 12 to ignore these circuits and boards.
We have three versions of power filter PCB. No difference between schematics, the one of them is
landscape, the another two is portrait orientation on PCB.
Document last modified and saved: 23 October 2011 6:15 PM
- 6
Simple gyrator and permanent Q active filter EQ project
7 -
Simple gyrator and permanent Q active filter EQ project
Schematics and Bill of Materials for gyrator EQ project
10 channel gyrator EQ mainboard
1
2
3
4
5
6
+15V Filt3
GND
6
5
4
3
2
1
P1
Header 6X2A
+15V Filt1
12
11
10
9
8
7
A
2
3
+15V
3
1
1
B
H3
8
A
3
U1A
TL072JG C1
1
1
10u
1
2
3
4
5
6
1
2
3
4
5
6
Header 6X2A
P5
7
8
9
10
11
12
7
8
9
10
11
12
Header 6X2A
GND
-15V Filt G
12
11
10
9
8
7
GND
+15V Filt2
GND
GND
1
2
3
4
5
6
1
2
3
4
5
6
Header 6X2A
7
8
9
10
11
12
1
2
3
4
5
6
Header 6X2A
P10
P11
GND
GND
1
2
3
4
5
6
1
2
3
4
5
6
Header 6X2A
R6
2
R5
3
A
U3A
TL072JG
1
6
5
B
1
2
3
4
5
6
10u
1M
Stereo gyrator EQ mainboard
Size
GND
10u
3
Quanti
ty
4
Comment
D
Number
Revision
A
Date:
File:
2
Value
GND
P14
Header 6X2A
Title
GND
1
C
7
8
9
10
11
12
Header 6X2A
GND
3.3k
GND
-15V Filt2
GND
12
11
10
9
8
7
3
B
U3B
TL072JG
7
4
5
10u
Description
Polarized Capacitor
(Radial)
GND
10/17/2011
Sheet of
D:\!Works\..\Gyrator EQ mainboard.SchDoc Drawn By:
5
Designator
Footprint
4 Cap Pol1
C1, C2, C3, C4
Cap, Tantal, 1mil
4 Connector
H1, H2, H3, H4
P1, P2, P3, P4, P5, P6, P7, P8,
P9, P10, P11, P12, P13, P14
Panel Connector 3 input Small
Model:Footprint
Resistor
3.3k
4 Res2
R1, R2, R4, R5
AXIAL-0.4
Resistor
1M
2 Res2
R3, R6
AXIAL-0.4
U1, U2, U3
dip-8
DIP; 8 Leads; Row Spacing 7.62 mm; Pitch 2.54 mm
14 Header 6X2A
Low-Noise JFET-Input Operational Amplifier 3 TL072JG
HDR2X6_CEN
Boards for gyrator
6
Connector; Header;
6x2 Position
Axial Device, ThruHole; 2 Leads; 0.4 in
Pin Spacing
Axial Device, ThruHole; 2 Leads; 0.4 in
Pin Spacing
Header, 6-Pin, Dual row
Printed Circuit
P13
U2B
TL072JG C3
7
6
5
4
3
2
1
8
6
C4
H4
B
7
8
9
10
11
12
Header 6X2A
R4
GND
1
7
8
9
10
11
12
Header 6X2A
7
8
9
10
11
12
Header 6X2A
3.3k
2
http://custompcb.blogspot.com/
http://diyguitarpa.blogspot.com/
P6
1
2
3
4
5
6
P12
Header 6X2A
12
11
10
9
8
7
6
5
4
3
2
1
GND
P9
7
8
9
10
11
12
GND
D
GND
+15V Filt G
P8
C
Header 6X2A
3
P4
7
8
9
10
11
12
GND
2
This is the schematic of the mainboard of
modular gyrator-EQ project. For this mainboard
required the gyrator circuit (10 board) and
power filter module. Visit the website for details,
PCB, and schematics.
7
8
9
10
11
12
H1
P3
P7
Header 6X2A
2
GND
-15V Filt1 GND
6
5
4
3
2
1
B
-15V Filt3
GND
-15V
5
3.3k
1M
GND
H2
2
R3
10u
2
A
U1B
TL072JG
7
6
R2
4
C2
3
U2A
TL072JG
1
1
2
3
4
5
6
4
8
GND
A
P2
R1
3.3k
EQ project
Notes
This is the mainboard for modular gyrator EQ. The mainboard contains required circuits and headers to
connect gyrator modules, potentiometers, and power filters. The finalized EQ can works with several frequencies and Q-s, and you can choose two versions of gyrator modules, one for stereo solutions with only
one stereo adjustable resistors, the second is two separated mono resistors for all bands for instrument
amplifications. Look at the difference on the PCB section.
Document last modified and saved: 23 October 2011 6:15 PM
9 -
C17
P6
C20
C10 C11
P5
R7 C6
C3
C18
C9
R18
R23R22
P4
C17
P6
C20
C10 C11
R12
C18
R8
R18
R17
C16
U3
R23R22
C14 C22
P4
H3
H4
C19
P1
P2
R16
C21 R21C13
C9
C7
C8
P5
R7 C6
C3
12
6
R20
P7
R15C15
R26
R4 R3 R19U4
R28 R27
H1
7
1
12
6
BOTTOM LAYER
7
1
TOP OVERLAY ON TOP LAYER
C24
R6
P3
U2
C4
R5
R25
C5
C23
C2
H2
U1
C1
R10
R1
C12R9 R11R13R14R24
R2
This the simplest ”all in one”
5 band EQ PCB. Very simple,
low noise circuit for home hi-fi
users. If you want more band,
check the modular version of
this project to insert any type
of gyrator modules to the
mainboard.
H3
H4
Notes
C14 C22
U3
C19
P1
12
6
R17
C16
P2
R16
12
6
R20
R15C15
C21 R21C13
R8
C7
C8
R4 R3 R19U4
R26
R28 R27
7
1
P7
R12
R6
P3
U2
C4
R5
R25
C24
H1
7
1
PCB TOP OVERLAY
TOP LAYER
C5
C23
C2
H2
U1
C1
R10
Simple gyrator and permanent Q active filter EQ project
C12R9 R11R13R14R24
R2
PCB for the simple EQ project
Top and bottom PCBs and overlay of simple 5 band EQ
R1
- 8
Simple gyrator and permanent Q active filter EQ project
Document last modified and saved: 23 October 2011 6:15 PM
- 10
PCB for the modular EQ project
Top and bottom PCBs and overlay of stereo gyrator module
Simple gyrator and permanent Q active filter EQ project
PCB for the modular EQ project
Top and bottom PCBs and overlay of 2 mono gyrator module
Notes
Stereo gyrator module
with one stereo potentiometer to adjust left and right
channel at once. This solution recommended for home
hi-fi users. This module most
be connected to the project’s mainboard.
Dupble-Mono gyrator module with two single potentiometers to adjust left and right
channel separately. This solution recommended for instrument amplifications. This module most be connected to the
project’s mainboard.
BOTTOM LAYER
Notes
TOP OVERLAY ON TOP LAYER
TOP LAYER
TOP LAYER
PCB TOP OVERLAY
11 -
PCB TOP OVERLAY
BOTTOM LAYER
Simple gyrator and permanent Q active filter EQ project
TOP OVERLAY ON TOP LAYER
Document last modified and saved: 23 October 2011 6:15 PM
- 12
Simple gyrator and permanent Q active filter EQ project
13 -
PCB for the modular EQ project
Top and bottom PCBs and overlay of power filters (ver.3)
Simple gyrator and permanent Q active filter EQ project
PCB for the modular EQ project
Top and bottom PCBs and overlay of power filters (ver.2)
BOTTOM LAYER
TOP LAYER
TOP LAYER
We have 3 versions of power filter
PCB. No difference between schematics, the one of them is landscape,
the another 2 is portrait.
BOTTOM LAYER
Notes
OVERLAY ON TOP LAYER
C3
C2
C3
7
P11
3
1
C2
R2
R2
C1
Q2
C7
C4
C1
C2
C6
C2
C6
C3
C8
C3
C8
7
1
R1
P1
P1
12
6
3
1
C4
C4
3
1
OVERLAY ON TOP LAYER
3
1
C8
C8
Q1
3
1
C6
R1
C1
Q2
C7
R1
We have 3 versions of
power filter PCB. No
difference between
schematics, the one of
them is landscape, the
another 2 is portrait.
C5
C7
Notes
3
1
Q2 R2
C6
12
6
C5
7
P11
R1
C1
Q1
Q1
3
1
C7
3
1
Q2 R2
PCB OVERLAY
Q1
C5
C5
C4
PCB OVERLAY
12
6
7
1
12
6
Document last modified and saved: 23 October 2011 6:15 PM
Simple gyrator and permanent Q active filter EQ project
- 14
PCB for the module of Parametric EQ project
Top and bottom PCBs and overlay of power filters (ver.1)
TOP LAYER
Notes
We have 3 versions of power filter PCB. No difference between schematics, the one of them is
landscape, the another 2 is portrait.
R2
C6 C2
Q1
C1
R1
3
1
C5
C7
Q2
C4
3
1
BOTTOM LAYER
C3 C8
P1
12
6
PCB OVERLAY
R2
C6 C2
Q1
C1
R1
3
1
C5
C7
Q2
C4
3
1
7
1
C3 C8
P1
7
1
12
6
OVERLAY ON TOP LAYER
Simple gyrator and permanent Q active filter EQ project
- 15
16 -
Simple gyrator and permanent Q active filter EQ project
PCB for the modular EQ project
The mainboard of 10 band EQ for gyrators
For 5 band EQ:
•
•
•
•
•
PCB OVERLAY
100Hz - 330n
300Hz - 100n
1kHz - 33n
3kHz - 10n
10kHz - 3.3n
For 10 band EQ:
•
TOP LAYER
Notes
This is the mainboard for 10 band gyrator EQ. Gyrator modules and power filter modules required. The frequency, Q and cut/
boost values depended on the parts of gyrator modules only. Look at the table on the gyrator’s schematic page, and read the
page about the math expressions.
Change all of the 50K adjustable resistors to 25K
Hz
C3
C4
R3
R4
31
6.8µ
100n
470�
100k
63
3.3µ
47n
390�
100k
125
1.5µ
33n
390�
100k
250
680n
22n
330�
82k
500
330n
10n
330�
100k
1K
150n
4.7n
330�
100k
2K
100n
2.2n
330�
82k
4K
56n
1n
390�
82k
8K
22n
470p
390�
82k
16K
10n
220p
390�
100k
The values of R3 is same as R1, the R2 is same as R4. Also look the
math expressions for another examples.
BOTTOM LAYER
OVERLAY ON TOP LAYER
Document last modified and saved: 23 October 2011 6:15 PM
- 17
Simple gyrator and permanent Q active filter EQ project
18 -
Simple gyrator and permanent Q active filter EQ project
PCB for the modular EQ project
The mainboard of 5 band EQ for gyrators
Notes
TOP LAYER
For 5 band EQ:
100Hz - 330n
300Hz - 100n
1kHz - 33n
3kHz - 10n
10kHz - 3.3n
For 10 band EQ:
•
Change all of the 50K adjustable resistors to 25K
Hz
C3
C4
R3
R4
31
6.8µ
100n
470�
100k
63
3.3µ
47n
390�
100k
125
1.5µ
33n
390�
100k
250
680n
22n
330�
82k
500
330n
10n
330�
100k
1K
150n
4.7n
330�
100k
2K
100n
2.2n
330�
82k
4K
56n
1n
390�
82k
8K
22n
470p
390�
82k
16K
10n
220p
390�
100k
PCB OVERLAY
•
•
•
•
•
This is the mainboard for modular gyrator EQ. The mainboard contains required
circuits and headers to connect gyrator
modules, potentiometers, and power
filters. The finalized EQ can works with
several frequencies and Q-s, and you
can choose two versions of gyrator
modules, one for stereo solutions with
only one stereo adjustable resistors,
the second is two separated mono resistors for all bands for instrument amplifications. Look at the difference on the
PCB section.
The values of R3 is same as R1, the R2 is same as R4. Also look the
math expressions for another examples.
BOTTOM LAYER
This is the mainboard for 5 band gyrator EQ. Gyrator
modules and power filter modules required. The frequency, Q and cut/boost values depended on the parts of
gyrator modules only. Look at the table on the gyrator’s
schematic page, and read the page about the math expressions.
OVERLAY ON TOP LAYER
Notes
Document last modified and saved: 23 October 2011 6:15 PM
Simple gyrator and permanent Q active filter EQ project
- 19
20 -
Simple gyrator and permanent Q active filter EQ project
Schematics and Bill of Materials for all EQ project
Schematic and BOM of power supply
The power supply for
1
2
3
4
A
R1
KBL04
C6
47n
3
B
D1
10 1W
IN
OUT
ADJ
A
2
+15V Out
+15V In
C2
2200u
C4
100n
D2
16V Zener
C3
47u
C5
100n
C7
47n
1
2
B
2
1
GND
15V AC - 2
H1
C8
47n
C9
47n
3
GND
2200u
C11
C10
2200u
R2
D3
16V Zener
100n
C13
-15V In
10 1W
C12
47u
H2
C14
100n
-15V Out
1
all gyrator EQ projects
15V AC - 1
C1
2200u
LM317BT
U1
6
1
3
5
C
2
ADJ
IN
OUT
C
3
U2
LM337BT
Title
Power supply
Size
D
http://custompcb.blogspot.com/
http://diyguitarpa.blogspot.com/
1
Description
2
D
Date:
File:
3
Quanti
ty
Value
Revision
10/17/2011
D:\!Works\..\Power supply.SchDoc
4
Designator
Sheet of
Drawn By:
5
6
Polarized Capacitor (Radial)
Cap Pol1
4 2200u
Polarized Capacitor (Radial)
Cap Pol1
2 47u
Footprint
ELCO 22 MM 4
MIL
Elco 12 mm, 2
mil pins
Capacitor
Cap
4 100n
RAD-0.3
Capacitor
Cap
4 47n
RAD-0.3
C6, C7, C8, C9
Full Wave Diode Bridge
KBL04
1
Bridge hor.
D1
Zener Diode
16V Zener
2
Connector
2
DIODE-0.7
D2, D3
panel connector
3 input big
H1, H2
Res2
2 10 1W
AXIAL-0.4
R1, R2
LM317BT
1
221A-04
U1
3 pin, 3 mil connector
Axial Device, Thru-Hole; 2 Leads; 0.4 in Pin
Spacing
TO, Thru-Hole, Vertical, Heatsink Mounted; 3 InLine Leads; Pitch 2.54 mm
3-Terminal Adjustable Negative Voltage
LM337BT
Regulator 1
221A-04
U2
TO, Thru-Hole, Vertical, Heatsink Mounted; 3 In-Line Leads; Pi
Resistor
3-Terminal Adjustable Positive
Voltage Regulator
Comment
Number
A
C1, C2, C10, C11
C4, C5, C13, C14
Model:Footprint
C3, C12
Radial Cap, Thru-Hole; 2 Leads; 0.3 in Pin
Spacing
Radial Cap, Thru-Hole; 2 Leads; 0.3 in Pin
Spacing
Diode, Thru-Hole; 2 Leads; 0.7 in Pin Spacing
Document last modified and saved: 23 October 2011 6:15 PM
Simple gyrator and permanent Q active filter EQ project
- 21
22 -
Simple gyrator and permanent Q active filter EQ project
PCB for all EQ project
The power supply PCB
TOP LAYER
PCB OVERLAY
H1
D1
U1
R1
1 2 3
C5
C9
C1
C8
C2
C6
U2
1 2 3
C14
D2
C12
R2
C7
C4
D3
C10
C11
C3
H2
C13
OVERLAY ON TOP LAYER
BOTTOM LAYER
H1
D1
U1
R1
1 2 3
C5
C9
C1
C8
C2
C6
1 2 3
C14
D2
C12
R2
C4
U2
C7
C10
D3
C11
C3
H2
C13
Document last modified and saved: 23 October 2011 6:15 PM
Simple gyrator and permanent Q active filter EQ project
- 23
24 -
Simple gyrator and permanent Q active filter EQ project
Help for gyrator EQ designs
Articles and images about gyrator EQ projects
With this project, very important to inform about the adjustable EQ designs. Because the modules can be set to
several adjustable values, maybe you need expressions to get the value of resistors or capacitors. Here is the page
to help.
Useful links and articles:
About Operator Adjustable Equalizers:
Math expressions,
articles for gyrator EQ
designs
•
•
•
•
•
•
•
•
Equalizer History
Industry Choices
Terminology & Definitions
Active & Passive
Graphics & Parametrics
Constant-Q & Proportional-Q
Interpolating & Combining
Phase Shift Examples
Design aspects of equalizers with lots of expressions.
The Evolution of an EQ Design
Software for EQ filter design
Images about this project:
•
•
•
•
•
The Piacsa album of projects
Prototype of 5 band and 10 band EQs
The new PCBs of modular gyrator EQ
PCBs and schematics of modular UREI clone parametric EQ project
RSS channel of my Picasa gallery
Document last modified and saved: 23 October 2011 6:15 PM
mined, and one will be chosen for this filter’s EQ sections.
1.1 TheSimple
Gyratorgyrator and permanent Q active filter EQ project
gyrator makes a nice RCL circuit. It gives symmetrical impedance (on a logarithmic
e) around the resonance frequency.
- 25
Help for gyrator EQ designs
symmetrical impedance makes it ideal for an equalizer.
Math expressions for gyrator design
C1
2
=>
C2
L
The Gyrator
The gyrator makes a nice RCL circuit. It
gives symmetrical impedance (on a logarithmic scale) around the resonance
frequency.
Rs
0
0
C1
R1
2
=>
C2
+
L
1
The active inductor is actually just a
Sallen and key HP filter drawn slightly
differently. It too functions as a series
connection between a capacitor and
an inductor. The major difference is
that the inductor has a parallel resistor.
page
11
of 27parallel resistor makes the impedRp
This
ance of the circuit NON-symmetrical
around the resonance frequency, thus
making the circuit less suited for EQ’s.
-
R2
Rs
0
Because of this parallel resistor, the
gyrator is preferred to implement the
inductor in the EQ sections of this filter.
0
Figure 11: The active inductor
L
(
C2 ⋅ R1 ⋅ R2 − R1
)
Rs
R1
2
s +
ωo
⋅s + ωo
Q
2
2
s +
EQnotch ( s)
Rp
2
s +
ωo
⋅s + ωo
Q
ωo
2
⋅s + ωo
Q ⋅ Kn
2
Kp and Kn are the gains of the EQ at their center frequency ωo. Their frequency response can
look like this:
10
The symmetrical impedance makes it
ideal for an equalizer.
he active inductor
inductor is factually just 1a Sallen and
slightly differently. It too
Rs key
R1 HP
+ R2filter
L drawn
C2 ⋅ R1 ⋅ R
res
2
2π
C
⋅
C
⋅
R
⋅
R
⋅
s a series connection 1between
2 1 2 a capacitor and an inductor. The major difference
nductor has a parallel resistor. This parallel resistor makes the impedance of the
N-symmetrical around the resonance frequency, thus making the circuit less suited
@delta-audio.com
EQpeak ( s)
Kp ⋅ ωo
2
⋅s + ωo
Q
www.delta-audio.com
Figure 10: The gyrator
C1
2
s +
1
R2
one version 1.0
The EQ is described by a transferfunction as any other second order system. There is
however a minor change to the way that it is written.
R2 − R1
this parallel resistor, the gyrator is preferred to implement the inductor in the EQ
this filter.
( )
dB Kp
5
Gain [dB]
-
R1
www.delta-audio.com
Simple gyrator and permanent Q active filter EQ project
3.3.2 The mathematical EQ
There are at least two ways of making
a capacitor act like an induction. One is
called the gyrator, and one is called the
active inductor. In the following the two
circuits will be examined, and one will
be chosen for this filter’s EQ sections.
C1
+
Active filter one version 1.0
26 -
0
( )
dB Kn
5
10
1
EQ peak
EQ notch
The SUM of the two EQs
10
freq [hz]
100
The two EQs have identical Qs of 2 and fo = 10 Hz. Kp = 2 and Kn = 0.5. The SUM of the two
filters is 0 dB witch means that two EQ sections can cancel each other out, if they share Q
and fo. The gain in dB must be the same for the two (Notch is negative of cause and peak is
positive)
The feature, that the EQs cancel each other when the have the same Q and “opposite”
gains; is called "reciprocal". This is a special type of EQ, since there are also circuits that are
"non-reciprocal".
jrm@delta-audio.com
Document last modified and saved: 23 October 2011 6:15 PM
page 13 of 27
Simple gyrator and permanent Q active filter EQ project
- 27
28 -
Simple gyrator and permanent Q active filter EQ project
Help for gyrator EQ designs
The frequency response of 10 channel modular EQ project
Previous PCBs and
images for simple 5
band and permanent Q
10 band EQ
Document last modified and saved: 23 October 2011 6:15 PM
- 29
30 -
Images about first prototype
5 band stereo permantnt Q graphic equalizer
The previous version of RANE Layout
basedsize:
permanent
Q project
1:1
I/O
Images about first prototype
5 band stereo graphic equalizer
The previous version of Layout
simplesize:
5 band
1:1 EQ
Simple gyrator and permanent Q active filter EQ project
I/O channel, connector for
input/output, VCC, VEE, etc...
http://microprojects.rentahost.net
http://microprojects.rentahost.net
R
R
C
R
C
R
C
C
P
P
C
D
P
C
P
B
+
C
C
C
C
C
C
+
+
R
C C
-
Q
+
C
C
+
Powertransistor or powerfet
Q
-15V
R
C
C
+
Single transistor or JFET
J
Q
C
5 channel stereo graphic EQ by SF
http://microprojects.rentahost.net
Q
U P
P
C
+
Integrated circuit
B
C
B
C
C
R
B
R
C
1
C
+
R
R
-
V+
R
R
C
C
Q
Q
C
C
C
V-
R
C
C
C
R
C
R
R
U
-
R
Left
U P
R
C
R
R
C
C
C
R
C
U P
C
R
C
R
R
R
R
R
R
C
C
R
R
R
R
R
R
C
R
C
C
R
R
B
R
R
C
C
U P
R
R
C
C
R
R
R
R
R
R
C
C
U
C
C
RightB
3
2
1:Cut
R 2:Boost
3:Sig
1 R3 2
R
R
C
R
R
C
C
R
R
R
R
R
R
C
C
R
R
C
-
Right
C
R
R
C
R
R
Left
R
R
R
R
R
+
P
Q
C
R
P
C
B
-
B
C
P
P
P
Right
+
C C+
Integrated circuit
C
R
Integrated circuit
Q
-
Integrated circuit
R
C C
C
C
R
+
Left
R
5 channel stereo permanent Q graphic EQ by SF
R
R
http://microprojects.rentahost.net
+
I/O
C
R
Q
C C+
+
U
R
C
C
C
C
R
+
U
R
C
Integrated circuit
U
R
R
I/O
U
C
U
C
R
U
R
R
R
Integrated circuit
U
R
R
R
R
R
R
R
R
R
B
C
C
R
C
C
2
R
C
C TR
+
U
R
R
Integrated circuit
Integrated circuit
U
R
R
R
C
C
Integrated circuit
C
Q
R
C
1:Cut
2:Boost
3:Sig
R
R
C
R
C
C
R
C
TR
RQ
Right
3
C
V+
3
Left
R
U
R
R
R
U
1
+
U
C
R
Potentiometer
P
J
R
R
TR
U
R
C
R
C
C
R R
R
J
R
C
Resistor
Potentiometer
+
D
R
C
R
R
U
R
1
Trimmer potentiometer
P
R
R
R
R
+
Trimmer potentiometer
R
R
R R
R
P
R
R
S
2
Powertransistor or powerfet
Potentiometer
Resistor
TR
R
R
Trimmer potentiometer
Single transistor or JFET
Q
R
R
J
C+
TR
-
J
U
TR
Resistor
R
Dual transistor or JFET
Q
-
1
S
R
Jumper
+
+
GND
Q
C
S
-
R
C
R
D
C
U
R
R R
RR
R
C
RR
U
R
+
3 2 D
R
C
RR R S C
R
R R
R
RR
R
C
R
VR R
J R
R
R
C
+
R
R
C
R
R
R R
C+
RR
+
I/O
+15V
R R
C+
Diode
Powertransistor or powerfet
Q
R C
C
R
R
C
D
+
R
RR R
R
R
R
R
R
C
Electrolic capacitor
Single transistor or JFET
R
C
C
R R
C+
Dual transistor or JFET
Q
+
D
R
TR
Good
quailty non-electrolic
J
Jumper
C + polarized
capacitor, for example Tantal
A
U
TR
S
R
R
+
P
C
Electrolic capacitor
C+
R
R
+
C
C
Non-polarized capacitor,
C ceramic, or some good quality
D WIMA capactors
like
Diode
D
R
J
3
+
C
C
2
1
+
R
C+
R
+
R
R
R R
TR
R
+
C
R
R
+
R
2
C
R
R
+
R
C
A
+
R
C R
R
C
+
R
TR
R
+
Good quailty non-electrolic
C + polarized capacitor, for example Tantal
S
Relay
D
R
+
+
R
C
R
-
-
Q
+
U
C C
+
R
U
C
C
+
R
D
C+
U
3
1
+
C
In 1
Electrolic capacitor
Dual transistor or JFET
3
I/O
R
I/O
R
I/O
TR
R
U
R
R
In 2
Diode
Q
2
1
R
I/O
U
R
+
+
R
Q
D
D
R
R
C
C
5 band stereo permantnt
Q graphic
equalizer
R
R
C
S
R
R
+
D
R
R
C
Layout size:S 1:1
S
C
R R
R
R
R
R
C
C
http://microprojects.rentahost.net
R R
R
TR
R
R
R
+
C
Good quailty non-electrolic
C + polarized capacitor, for example Tantal
C
R
+
B
TR
I/O
Non-polarized capacitor,
C ceramic, or some good quality
like WIMA capactors
R
GND
GND
R
+
Relay
Relay
I/O channel, connector for
input/output, VCC,
VEE, etc...
Non-polarized
capacitor,
C ceramic, or some good quality
like WIMA capactors
C
C
Out 2
S
C
R
TR
I/O
+
D
I/O
Out 1
S
TR
+
I/O
I/O channel, connector for
input/output, VCC, VEE, etc...
+
S
+
Simple gyrator and permanent Q active filter EQ project
5 channel stereo permanent Q graphic EQ by SF
http://microprojects.rentahost.net
Document last modified and saved: 23 October 2011 6:15 PM
English blog and PCB order: http://custompcb.blogspot.com/
Hungarian blog and PCB order: http://diyguitarpa.blogspot.com/
The Youtube Channel • Picasa gallery • Email: gitarfogas@gmail.com
Gyrator EQ-public-doc.pdf (PDF, 2.84 MB)
Use the permanent link to the download page to share your document on Facebook, Twitter, LinkedIn, or directly with a contact by e-Mail, Messenger, Whatsapp, Line..
Use the short link to share your document on Twitter or by text message (SMS)
Copy the following HTML code to share your document on a Website or Blog