From: "Le Cleac'h J.-M." <lecleach@cgi.ensmp.fr>
Subject: Heath and Marantz tube crossovers schematics
Hello,
You'll find here few ASCII schematics for Heath and
Marantz tube crossovers. They were given in
L'Audiophile No 11 old sery July 1979. In the same
paper there is another tube crossover designed by Gerard
Chretien now at the head of Focal (i'll try to send an ASCII
schematics of that one tomorrow). (to be print in courier font)
Best regards
Jean-Michel Le Cleac'h, Paris, France
**************************************************************
HEATH X0-1
High pass filter
B+ .
| .
o---------------o .
| | .
R4 | .
| Plate .
12AX7 o----C2---o---Grid 12AX7 .
Plate | Cathod .
INPUT--R1--o--C1--o--Grid | | .
| | Cathod | o----------o---C4---o HPF .
| | | R6 | | .
| | o----o | R7 | .
| | | | | | | .
R2 R3 R5 C3 o-----o | .
| | | | | | .
| | o----o R8 | .
| | | | | .
| o----o---------------o--GROUND | .
| | .
o--------------------------------------o .
*******************************************************************
HEATH X0-1
Low pass filter
B+
|
o-------------------o
| |
R4 |
| Plate
12AX7 o--R9--C2--o---o--Grid 12AX7
Plate | | Cathod
INPUT--R1--o--R3--o--Grid | | |
| | Cathod | | o---------o--C5--o LPF
| | | | R6 | |
| | o----o | | R7 |
| | | | | | | |
R2 C1 R5 C3 C4 o----o |
| | | | | | |
| | o----o | R8 |
| | | | | |
| o----o----------o--------o-GROUND |
| |
o-----------------------------------------o
****************************************************************
Marantz
High pass filter
B+(1) B+ (2) B+ (1)
| | |
| | |
| | |
12AX7 | R10 | 12AX7
Plate | Plate
INPUT-C1-o--Grid o-----o-Grid
| Cathod | | Cathod
| | Plate | |
R1 o-R3-o-C2-o-C3-o-C4-o-Grid R11 o--------o-C5-o HPF
| | | | | | Cathod | | |
| | | R6 R7 R8 | | | |
| | | | | | | | | |
| | | o----o----o | | | |
| | | | | | | |
+ | | + | + | |
Pol R2 | Pol R9 Pol R12 |
- | | - | - | |
| | | | | | | |
o----o | o-------------o-----o---o-GROUND |
| | |
GROUND o-------------------------------------o
Pol = DC supply for fixed grid potential
*******************************************************************
Marantz
Low pass filter
B+(1) B+ (2) B+ (1)
| | |
| | |
| | |
12AX7 | R8 | 12AX7
Plate | Plate
INPUT-C1-o--Grid o----o-Grid
| Cathod | | Cathod
| | Plate | |
R1 o-R3-o-C2-o--o-R6-o--Grid R9 o--------o-C5-oLPF
| | | | | | Cathod | | |
| | | R5 C3 C4 | | | |
| | | | | | | | | |
| | | o--o----o | | | |
| | | | | | | |
+ | | + | + | |
Pol R2 R4 Pol R7 Pol R10 |
- | | - | - | |
| | | | | | | |
o---o | o------------o-----o---o-GROUND |
| | |
GROUND o------------------------------------o
Pol = DC supply for fixed grid potent
****************************************************************
Hello, it is me again,
Here is the ASCII schematics of the AudioResarch
(6db/octave) tube crossover.
Best regards
Jean-Michel Le Cleac'h
******************************************************************
AudioResearch
Low pass filter
B+(1) B+(2) B+(3) B+(4)
| | | |
R3 | R10 |
| Plate GROUND | Plate
o---Grid | o---Grid
| Cathod C2 | Cathod
Plate | | Plate |
INPUT-R1-o-Grid o-C1-o-o-R7-o-o-Grid o-C3-o--o-R13-oLPF
| Cathod | | | | Cathod | | |
| | | | | | | | | |
R6 R2 R4 R5 | R8 R9 R11 R12 |
| | | | | | | | | |
| o-----o----o | | o-----o----o |
| | | | | |
| GROUND | | GROUND |
| | | |
o----------------o o-----------------o
All tubes = 12AX7
***************************************************************
AudioResearch
High pass filter
B+(1) B+(2) B+(3) B+(4)
| | | |
R3 | R11 |
| Plate GROUND | Plate
o---Grid | o---Grid
| Cathod R7 | Cathod
Plate | | Plate |
INPUT-R1-o-Grid o-C1-o-o-C2-o-o-R9-Grid o-C3-o--o-R14-oHPF
| Cathod | | | | Cathod | | |
| | | | | | | | | |
R6 R2 R4 R5 | R8 R10 R12 R13 |
| | | | | | | | | |
| o-----o----o | | o-----o----o |
| | | | | |
| GROUND | | GROUND |
| | | |
o----------------o o--------------------o
All tubes = 12AX7
****************************************************************
Larsen and Chretien (audiophile No 11)
High pass filter 7kHz, 12 dB/octave, (Bessel second order)
B+(1) B+(2) B+(3) B+(4) .
| | | | .
R3 | V2 | | .
| Plate o----o | .
o---Grid | | | .
| Cathod R7 | V3 | .
Plate | | Plate | .
INPUT-R1-o-Grid o--o-C2-o-C3-o--Grid | .
| Cathod | | | | Cathod | .
| | V1 | | | | | Plate .
| | | | | | o-----o--Grid V4 .
| | | | | | | | Cathod .
| | | | | | | | | .
| | | | | | | | o--C4--o HPF .
| | | | | | | | | .
R5 R2 R4 C1 R9 R6 R8 | R10 .
| | | | | | | | | .
| o-----o | | o----o | | .
| | | | | | | .
| GROUND | | GROUND | GROUND .
| | | | .
o------------o o---------------o .
V1 and V2 = 12AX7
V3 and V4 = 12AT7WA
R1 = 150 kohms
R2 = 2.2 kohms
R3 = 301 kohms
R4 = R8 = R10 =105 kohms
R5 = 402 kohms
R6 = R7 = 81.2 kohms
R9 = 38.45 kohms
C1 = C4 = 0.2 microfarads (200VAC)
C2 = C3 = 560 picofarads
************************************************************
Low pass filter 7kHz, 12 dB/octave, (Bessel second order)
B+(1) B+(2) B+(3) B+(4) .
| | | | .
R3 | V2 | | .
| Plate | | .
o---Grid | | .
| Cathod | V3 | .
Plate | Plate | .
INPUT-R1-o-Grid o--o-R6-o-R7-o--Grid | .
| Cathod | | | | Cathod | .
| | V1 | | | | | Plate .
| | | | | | o-----o--Grid V4 .
| | | | | | | | Cathod .
| | | | | | | | | .
| | | | | | | | o--C4--o LPF .
| | | | | | | | | .
R5 R2 R4 C1 C2 C3 R8 | R10 .
| | | | | | | | | .
| o-----o | | o----o | | .
| | | | | | | .
| GROUND | | GROUND | GROUND .
| | | | .
o------------o o---------------o .
V1 and V2 = 12AX7
V3 and V4 = 12AT7WA
R1 = 150 kohms
R2 = 2.2 kohms
R3 = 301 kohms
R4 = R8 = R10 =105 kohms
R5 = 402 kohms
R6 = R7 = 47.5 kohms
C1 = C4 = 1 microFarad (200VAC)
C2 = 505 picoFarads
C3 = 453 picoFarads
***************************************************************
Larsen and Chretien (audiophile No 11)
High pass filter 5kHz, 24 dB/octave, (Bessel fourth order)
B+(1) B+(2) B+(3) B+(4) .
| | | | .
R3 | V2 | | .
| Plate o---o | .
o-Grid | | | .
V1 | Cathod R7 | V3 | .
Plate | | Plate o---o .
INPUT-R1-o-Grid o-o-C2-o-C3-o-Grid | | .
| Cath | | | | Cathod R13 | .
| | | | | | | | Plate .
| | | | | | o-o-C5-o-C6-o-Grid V4 .
| | | | | | | | | | Cathod .
| | | | | | | | | | | .
| | | | | | | | | | o-o-C4-o HPF.
| | | | | | | | | | | | .
R5 R2 R4 C1 R9 R6 R8 | R11 R12 R10 | .
| | | | | | | | | | | | .
| o---o | | o---o | | o---o | .
| | | | | | | | | .
| GROUND | | GROUND | | GROUND | .
| | | | | | .
o---------o o----------o o----------o .
V1 and V2 = 12AX7
V3 and V4 = 12AT7WA
R1 = 150 kohms
R2 = 2.2 kohms
R3 = 301 kohms
R4 = R8 = R10 =105 kohms
R5 = 402 kohms
R6 = R7 = 81.2 kohms
R9 = R11 = 38.45 kohms
R12 = R13 = 162.4 kohms
C1 = C4 = 2 microfarads (200VAC)
C2 = C3 = C5 = C6 = 560 picofarads
****************************************************************
High pass filter 5kHz, 24 dB/octave, (Bessel fourth order)
B+(1) B+(2) B+(3) B+(4) .
| | | | .
R3 | V2 | | .
| Plate | | .
o-Grid | | .
V1 | Cathod | V3 | .
Plate | Plate | .
INPUT-R1-o-Grid o-o-R6-o-R7-o-Grid | .
| Cath | | | | Cathod | .
| | | | | | | _ _ Plate .
| | | | | | o-o-R6-o-R7-o-Grid V4 .
| | | | | | | | | | Cathod .
| | | | | | | | | | | .
| | | | | | | | | | o-o-C4-o LPF.
| | | | | | | | | | | | .
R5 R2 R4 C1 C2 C3 R8 | C5 C6 R10 | .
| | | | | | | | | | | | .
| o---o | | o---o | | o---o | .
| | | | | | | | | .
| GROUND | | GROUND | | GROUND | .
| | | | | | .
o---------o o----------o o----------o .
V1 and V2 = 12AX7
V3 and V4 = 12AT7WA
R1 = 150 kohms
R2 = 2.2 kohms
R3 = 301 kohms
R4 = R8 = R10 =105 kohms
R5 = 402 kohms _ _
R6 = R7 = 47.5 kohms, R6 = R7 = 47.5 kohms
R9 = R11 = 38.45 kohms
R12 = R13 = 162.4 kohms
C1 = C4 = 1 microfarads (200VAC)
C2 = C5 = 1010 picofarads
C3 = C6 = 453 picofarads
***************************************************************
Hello,
Here is an ASCII schematic for the Bessel crossover
(2nd and 4th orders) designed by Larsen and Chretien.
Best regards
Jean-Michel Le Cleac'h
*****************************************************
HV supply for the Larsen - Chretien tube crossover
B+ B+ B+ B+
(1) (2) (3) (4)
PT R | | | |
______ ,---[>|---o--o-L1-o-R1-o-R2-o-R3-o-R4-o
)|( | | | | | | |
)|( | C1 C2 C3 C4 C5 C6
MAINS )|(-o GROUND | | | | | | |
)|( | o----o----o----o----o----o
______)|( R | |
`---[>|---o GROUND
PT = POWER TRANSFORMER 2 x 260VAC at secondary
R
-[>|- = 1N4007 Silicon rectifier
L1 = 12 H 30 mA (400ohms)
R1 = R2 = 500 ohms
R3 = R4 = 1 kohms
C1 = C2 = 60 microfards 450V
C3 = C4 = C5 = C6 = 20 microfards 450V
*************************************************