<%@LANGUAGE="JAVASCRIPT" CODEPAGE="65001"%> SOWTER VINTAGE AUDIO TRANSFORMERS
Sowter vintage audio trnasformers
Sowter Audio Transformers (E A Sowter Ltd.)

VINTAGE RECORDING STUDIO PRODUCTS
replacement vintage audio transformers

A SERVICE for recreation or replacement or repair of vintage studio compressors, microphone amplifiers, equalizers, bridging and distribution amplifiers etc using tubes or transistors. There may be small differences in dimensions, taps and in the detailed specification but we are confident these transformers will have the "original sound"

DRIP ELECTRONICS are now selling PRINTED CIRCUIT BOARDS and other componrnts for the equipment listed below

CUSTOM DESIGN SERVICE We are extending our custom design service to include this type of transformer. We will not make a charge for the design provided we accept the requirement as being of general interest. We can work from circuits, actual transformers loaned to us or from specifications. We may offer the service on a "best efforts" basis if we cannot be sure of meeting a particular performance.

EQ INDUCTORS  Please see separate page

GENERIC PRODUCTS Many manufacturers used generic transformers which you may find on our Pre-Amp and Line Amp page or our Pro-Audio page. Please feel free to contact technical support for assistance.

PRICE and SHIPPING cost can be found by clicking on the "Buy" link or using SEARCH an using the type number as the search word

PRO VINTAGE PRODUCTS 
Quote
shipping
 TYPE
 PRICE Equipment Description Voltage
ratio		 Z ratio Total DC res ref pry
ohms		 Max level at 50 Hz
 Package size/style/core
TRANSFORMERS WHICH FIT DRIP ELECTRONICS PC BOARDS
Buy 9643

Fairchild type 670

Drip Electronics

 Control amp output 4:1
9:1NFB		 10kCt/600
+NFB		 950 75 V rms
output		 "SI" M6 Shrouded
Fits original can.
Buy 8344 Signal amp output 9+9: 1+1 60k/600 940 +30 dBu
output		 "m" M6 Mumetal can
Buy 8345 Control amp input 17+17:
1+1		 600/170k 34 +16 dBu "j" Mumetal, Mumetal can
Buy 8346 Signal amp input 9+9:
1+1		 600/50k 65 +24 dBu "k" Mumetal, Mumetal can
Buy 9970 £87.35

EMI REDD47 etc

Drip Electronics "Four Seven"

 Microphone input 1:7
35%
secy tap		 200/10k    

"jE" Mumetal
Mumetal canMounting options
Buy 9980 £87.35 Line Output 7:1+1 30k/600+600     "jE" 50% Mumetal/M6
Mumetal canMounting options
Buy 1231 £87.35

Altec 436C Compressor

Drip Electronics

Bridging input 1:1.23CT 15k/80k   1.1k Ohms   +30 dBu "j" Mumetal, Mumetal can
Buy 1232 £68.67 Line Output 12.4CT:1+1 23KCT/150+150 25 Ohms (sec) +28 dBu "k" M6
Package options
Buy 9795 £115.59 Teletronix
LA-2A Compressor

Drip Electronics Opto4

Opto5

More info

 Mains  ww Primary "SE" M6
Shrouded
Buy 0295 £129.25 Mains Transformer WW primary 2 x 120,110  V. Electrostatic shield. 250-0-250 V  40 mA. 6.3V CT at 2 A.  "SF"
M6 Shrouded
Buy 0208 £129.25 Mains Transformer 240, 220, 200, 0, -10 Primary. Electrostatic shield. 250-0-250 V  40 mA. 6.3V CT at 2A.  "SF"
M6 Shrouded
Buy 1009 £56.36 Amp input

UTC A10 replacement		 1:9.1 600/50k 42 +15 dbu "f" Mumetal 
Mumetal can
Buy 1010 £77.57 Amp output
UTC A24 replacement		 5:1 15k0/600 30 ref secy +30
dBu
output		 "k" open
50% Mumetal
Buy 1290 £79.85 Amp output
UTC A24 replacement		 5:1 15k0/600 30 ref secy +30
dBu
output		 Round can included
30% Mumetal
Buy 9527 £145.87

Pulteq
EQP-1A

Schematic

Drip Electronics

Mains transformer for 1 or 2 units.  WW Primary. Electrostatic screen
250-0-250 at 60 mA. 6.3 V CT@ 1.5 A. 
6.3-5-0 V @ 1.0 A for rectifier and pilot light.  50/60 Hz
Larger than original but still fits on chassis with minor modification.		 "SJ" M6

Shrouded
Buy 3603 £49.79 EQ input
(Triad HS-56)		 1CT:1 600/600 150 +17 dBu "e" Mumetal, Mumetal can
Buy 9330 £49.79 Amp input
(Triad HS-29)		 1:2CT 2k5/10k
 112 +16 dBu "e" Mumetal, Mumetal can
Buy 9530 £52.79 Amp output
Peerless S-217-D		 10CT:1+1
NFB 4% of primary		 15k/600 
15K/150		 39
ref secy		 +23 dBu "j" open 50%
Mumetal
Buy 9325 £52.06 Passive EQ inductor 150/82/68/47/33/27 mH
15/11/10/8/6/5 ohms		 Ferrite
"e"  Mumetal can
Buy 8650 £76.48

Universal Audio / Urei UA175B Sta Level

Drip Electronics

 Output 9CT:1 15k/185 ohm   +28 dBu "SA" M6 Open
Buy 1009 £56.36 Input
Similar to UTC A-10		 1:9.1:1 600/50k 14 Ohms   "f" Mumetal 
Mumetal can
Buy 1133

Interstage
Tested with Drip PCB Similar to
UTC A19

 2.3:1 180k/15k 4k +40 dBu Radiometal
Mumetal can
Buy 9062   Drip Electronics Sta-Level (Micro) Input 1CT:4+4 600/50K CT 103 ref pry +42 dBu "j" Mumetal, Mumetal can
Buy 9185 £83.33 Output 7.3:1 8kCT/150 40 ref sec +40 dBu "SJ" M6 Shrouded
Buy 8345 Fairchild 666 Input
Similar to
UTC Y6431
 17+17:
1+1		 600/170k 34 +16 dBu "j" Mumetal, Mumetal can
Buy 1160 £90.91 Output
Similar to Chicago
BO-1		 10:1 or 5:1 15k/150+150   +30
(output) 		Gapped M6
Package options
Buy 1255 £52.25 Side chain output 6.32 :1 20k/500 66 ref secy   "A" U-Clamp
Buy 1960   Telefunken V72 Input 1+1:20 50/47k OR
200/47k		   +12 dBu "e" Mumetal, Mumetal can
Buy 1275   Output (original ratio) 11.2:1 76k/600 Ohms

20 Ohms

 +14 dBu at 40 Hz "j" 100% Mumetal
Buy

9375

 £66.38 Plate choke 750H approx at 1kHz with no dc 
DCR  14.6 kohm 		 "Aj" Gapped M6
Buy 9835 £85.29 RCA BA-6A
Limiting amplifier

Drip Electronics PCB
 Input  1CT:4.08CT 600/150 
to 10k		 131 +16 dBu "Ii" Mumetal,
Mumetal can
Buy 9830 £137.39 Interstage 1CT:1 10KCT/10K 1680 +36
dBu		 "Jk" Radiometal
Mumetal can
Buy 9770 £139.00 Output for 6V6 PP 3.65 CT:1 8k/600 506 +30
dBu
output		 "SK" Fully Shrouded
M6
Buy 1260   Universal
1176F		 Input 1:1.158 200/500     "e" Mumetal, Mumetal can
OTHER PRO VINTAGE TRANSFORMERS
Buy 9186 £111.66 Altec 1566a Microphone Preamp.  Circuit on request Mains ww primary.  110 V 30 mA, 22V CT 0.5 A "SD" M6 Shrouded
Buy 4935 £49.79 Mic input  1CT:7 200CT/100k 40 ohms +12 dBu "e" Mumetal, Mumetal can
Buy 8940 £76.48 Output 3:1 5k/600 15 ohms (sec) +28 dBu "k" 70% Mumetal Open frame
Buy 9820 £51.33 API 312 Mic Pre and Line amp Input 1:4.37 150/600:11.5k 149 0 dBu "e" Mumetal, Mumetal can
Buy 9825 £50.78 Output 1+1+1+1 75:300+75 31.5 +30 dBu "j" M6
Buy 9775 £74.07 Langevin
AM 16		 Input 1Ct+1CT:4+4 50,150,600/
2k5 + 2K5		   +17 dBu "f" Mumetal
Mumetal can
Buy 9765 £74.07 Output 1+1+1+1:1+1  600/150,600    +37 dBu "j" M6
Mumetal can
Buy 1120 £64.85 Telefunken V72 Output (alternative ratio) 9:1 50k/600 11.5 Ohms (sec)+12 dBu at 40 Hz "j" 70% Mumetal
Buy 1110 £92.28 Telefunken V76 Output 9:1 50K/600 10 Ohms
ref secy		 +18 dBu
at 30 Hz		 "A" Open frame.
50% Mumetal
Buy 1004 £80.73 Telfunken V76 Input 0.5 + 0.5:30 200/180k 9
ohms		 +12
dBu		 "j" Mumetal
Fits orig. can
Buy 1130 £67.06 Telfunken V76 Plate Choke

500H approx
DCR = 5.7 K Ohms

 "A" Gapped M6. U-Clamp
Buy 9129 £52.79 Telfunken V74 Output 8:1+1+0.7 2K/30ohms 584 ohms +20 dBu "j" M6 U-Clamp
Buy 8540 £49.79 Gates M5167 compressor. (PP 6V6's) Circuit  Line input  1:4 600/10kCT 120 +16 dBu "e" Mumetal, Mumetal can
Buy 9185 £83.33 Line output 7.3:1 8kCT/150 40 ref sec +40 dBu "SJ" M6 Shrouded
Buy 9062 £91.68 CCA Electronics Corp LA-1D

Circuit

 Line Input 1CT:4+4 600/50K CT "j" Mumetal, Mumetal can
Buy 9890 £95.07 Line Output 5.77CT:1 20K/150+150 "SD" M6 Shrouded
Buy 9084 £68.69 Ampex 351 Line out 5.55CT:
1CT+1		 15K/"600"
+NFB		 1500 +38 dBu "SA" M6
Shrouded
Buy 9735 £68.35 Ampex 350/351 Input 1+1:32 50+50/50K 28 +12 dBu "fF"  Mumetal,
Mumetal can
Buy 8751
 £52.25 Neve
Darlington  Line Amplifier		 600 ohm line Output transformer 1:1.5
 N/A 39 +30 dBu "OB" open
U-Clamp M6
Original version P/N L01166
Buy 9160 £52.25 600 ohm line Output transformer 1:1.5 N/A 37 +27 dBu "OA" open
U-Clamp M6, P/N L01166 reduced size
Buy 9780 £52.25 600 ohm line Output transformer 1:1.5 N/A 39 +30 dBu "OB" open
U-Clamp M6
Ungapped for use with pin "F" only. P/N L02567/T1801
Buy 9145 £53.27 Input transformer
P/N 10468		 1+1:2+2 300/1k2 to 1k2/4k8 190 +18 dBu "e" Mumetal,
Mumetal can, Normal laminations.
Buy 9165 £53.27 Input transformer
P/N 31267		 2+2:1+1 10k/2k4 
to 2k4/600		 1k8 +24 dBu "e" Mumetal,
Mumetal can
Buy 7490 £52.91 Helios etc Input transformer
Lustraphone M10 		 1:10 tap for 1:1 200/20K  _9 dBu "eE" Mumetal,
Mumetal can
Threaded boss
Buy 7456 £55.57 Trident A range, B range, etc Input transformer
Marinair ZUTT012a		 1:5.9 600/30K 179 +20 dBu "jE" Mumetal
Mumetal can
Buy 9930 £52.06 Gyraf Passive EQ 267 mH inductor tapped at 269,169,69,22 mH Replaces separate 100,100,47.22 mH inductors shown on schematic "e" Ferrite
Mumetal can
Buy 9540 £49.79 Input 1:1 200/200 ohms +10 dBu "e" Mumetal,
Mumetal can
Buy 8403 £50.78 Output 1:1+1 600:150+150 65 ohms +34 dBu "j" M6
Options
Buy 9835 £85.29 RCA BA-6A
Limiting amplifier		 Input  1CT:4.08CT 600/150 
to 10k		 131 +16 dBu "Ii" Mumetal,
Mumetal can
Buy 9830 £137.39 Interstage 1CT:1 10KCT/10K 1680 +36
dBu		 "Jk" Radiometal
Mumetal can
Buy 9770 £139.00 Output for 6V6 PP
 3.65 CT:1 8k/600 506 +30
dBu
output		 "SK" Fully Shrouded
M6
Buy 1195 £137.39

RCA 86-AL
Limiting amplifier
Suitable for RCA 86-A

 Interstage 1+1:1.4 10k+10k/20k 1610 +36 dBu "Jk" Radiometal
Mumetal can
Buy 1100 £87.35 Ferrograph tape head input transformer For series 3 etc 6:1 300/10k     "e" Mumetal,
Mumetal can
Buy 1200   Universal Audio 1008A Mic Pre amp Output 3.42:1 7K/600 plus NFB winding 1052 +24 dBu "k" M6 Mumetal can
Buy 1166   EMT 262 Reverb Input from plate 1:35 40/50k    

"c" Mumetal
Mumetal can

Leads or PCB option