ELAN
AUDIO
2 STEEL COURT SOUTH GUILDFORD WA 6055
PHONE (08) 9277 3500
FAX (08) 9478 2266
email poulkirk@elan.com.au
web www.elan.com.au
Technical Description.
Universal Module UPP-01
Stereo RIAA Compensated Moving Magnet Pick-Up Pre Amplifier
The UPP-01 is a practical module designed to fit into the RUC-01 Universal Casing
Features
Stereo RIAA Compensated Pick-Up Pre Amplifier
Suitable for Moving Magnet type Cartridge
RCA Phono Connectors on Inputs
Resistive Cartridge Loading, Link Adjustable 47 K Ohms and 68K Ohms
Capacitive Cartridge Loading, Link Adjustable, 50, 100, 150, 200 and 250 pF
Passive Equalisation for minimum TID (Produces less Surface Noise)
LF Cutoff –3 dB at 20 Hz
Multiturn Channel Gain Control Trim-Pots
Mono Link
Balanced Line Output
Technical Description
DC Power, +15V and –15V DC is provided via a 10 Pin Box Header on the PCB
Pins, 1 and 2 +15V DC, 3 and 4 –15V DC, 5 and 6 N/c, 7, 8, 9 and 10 Ground
Audio Input RCA Phono Sockets
Audio Output 9 Pin Male “D” Connector located at one end of the UPP-01 Module
Pins, 1 and 6 Left Output, Pins 2 and 7 Right Output, Pin 3 Ground
The circuit used for Left and Right channel is identical with only the Left channel described here
Input is via an RCA Phono Connector
Input loading resistors R2 47K and R3 22K are provided to give the correct resistive loading to the PickUp Cartridge providing and provides a choice of 47K with the Link In and 68K with the Link Out
Most common specified load is 47K with some cartridges specified for 68K
R1 47 Ohms is fitted to provide some RF protection to the input stage
C1, C2 and C3 are provided to give the correct capacitive loading to the Pick-Up Cartridge and can by
switching provide 50pF, 100pF, 150pF, 200pF or 250pF s the input
The required input load resistance and load capacitance for a particular Pick-Up Cartridge is normally
specified by its manufacturer and are very important for best frequency response performance
1
The capacitive loading is calculated adding the capacitance of the Pick-Up Arm and connecting cable, if
known, and adding the extra required capacitance using the Links and Capacitors provided in the UPP01 Module
If the Arm and Cable Capacitance is not known, the best method is by using a suitable Test Record
such as the CBS BTR-150 Broadcast Test Record or similar
Unlike most RIAA Compensated Pick-Up Pre Amplifiers, the UPP-01 use passive compensation instead
of the more common and simpler feedback compensation
The first stage of amplification is by IC-1 providing a flat frequency response and a gain of about 34 dB
The operation of IC-1 without reactive components in the feedback loop, and a very benign 12K loading is
largely responsible for a cleaner and more transparent treble, and a notable reduction in record surface
noise compared to most feedback compensated RIAA Pre Amplifiers
The required Treble Roll-off is done by the passive RC combination formed by R11 and C9
This is followed by an active High Pass Filter formed by IC-3:A in combination with C11, C12, R13 and
R14
The required Bass Boost is done by the passive RC combination formed by R21, R23 and C17
Overall Gain Control is by a 10K Pre-Set Potentiometer connected in the feedback loop of IC-3:B
Left and Right Channels may be combined to Mono by inserting the Mono Link on the Module
The balanced differential output is provided by a SSM-2142 IC IC-5 with the output being protected by a
22 Ohm resistor in each output leg
Notes and Comments
The UPP-01 RIAA Compensated Pick-Up Pre Amplifier Module is specifically designed for Professional
use with a conventional Moving Magnet Pick Up Cartridge
As factory standard, for cost reasons, It utilises a conventional low cost FET Input TL-071 Operational
Amplifier in the first or front end Amplifier Stage
The TLO-071, thanks to the passive RIAA compensation circuit used in the UPP-01 provides entirely
acceptable Noise and Distortion performance for Broadcast and other Professional applications
To special order, and at extra cost, the UPP-01 may be supplied with the exotic and very expensive LT
1115 Op-Amp and precision selected components in the compensation circuit
We have serious doubts that the extra cost involved using the LT 1115 is worth while as the
improvement in Signal to Noise Ratio will be only about 3 dB and in addition, the more precise RIAA
Compensation is probably not noticeable
After all, Tape-Hiss from the Studio Tape Recorders and other noise present on the majority of LP
Records far exceeds the noise generated by the TL-071 Pre-Amplifier IC used in the UPP-01
Furthermore, the frequency response of the average LP probably deviates as much as 3 or 4 dB from the
standard RIAA curve making compensation circuits of greater precision than + and – 0.5 dB most likely
meaningless and a waste of effort
Even Professional Test Records suffer from Frequency Response deviations and in some cases come
supplied with correction charts
2
Furthermore, the High Frequency Response will change and deteriorate after a number of playing’s
Inherently, the frequency response of the UPP-01 follows the recommended RIAA playback response
within 0.5 dB from 30 Hz to 20 KHz and is deliberately rolled of by 1 dB at 25 Hz and 3 dB at 20 Hz
We attained the following playback results from the CBS BTR-150 Broadcast Test Record, using a
Technics SP-10 Turntable, SME 2009 Mk II Improved Version Tone Arm, Stanton 680 Mk II Moving
Magnet Cartridge, Stanton 680 EL Mk II Stylus Assembly
Load resistance and capacitance correctly matched to the UPP-01 Module
Frequency
Left Channel
Right Channel
16 KHz
14 KHz
12 KHz
10 KHz
8 KHz
6 KHz
5 KHz
4 KHz
3 KHz
2 KHz
1.5 KHz
1 KHz
800 Hz
600 Hz
500 Hz
400 Hz
300 Hz
200 Hz
150 Hz
100 Hz
80 Hz
60 Hz
50 Hz
+ 1.0
+ 0.5
+ 0.2
0
0
0
0
- 0.5
0
0
+ 1.0 dB
+ 1.2 dB
+ 0.8 dB
+ 0.4 dB
0
0
0
- 0.5 dB
- 0.2 dB
0
dB
dB
dB
dB
0
0
0
+ 0.3
+ 0.2
+ 0.2
+ 0.4
0
+ 0.2
0
0
0
0
dB
dB
dB
dB
dB
Reference 1 KHz
0
0
0
0
0
+ 0.2
+ 0.1
0
+ 0.1
0
0
+ 0.2
0
dB
dB
dB
dB
Sound Clarity, Imaging and Stereo Separation was perceived as exceptionally good, no doubt caused by
a number of factors such as a very good Tone Arm and that the Cartridge was correctly loaded
Record Surface Noise was notably low, probably thanks to the Passive Equalisation
Perceived distortion was low when observed as waveforms on an Oscilloscope with the trace noticeably
steady probably caused by the good Tone Arm, Correct Loading and the High Pass (Low Cut) filter in
the UPP-01
Factory Configuration
Links
Input Resistance
Input Capacitance
Mono Link
Set for 47K Load
All Links Fitted
Not Fitted
Gain Setting
3.6 mV 1 KHz in + 4 dBmW out
3
Technical Specifications
Input
Type
Impedance
Capacitance
Connector
Unbalanced High Impedance Selectable
47K or 68K
Selectable 50, 100, 150, 200 or 250 pF
RCA Phono
Output
Type
Impedance
Max Level
Differential Balanced
About 50 Ohms
+ 25 dBmW into 600 Ohms
Performance
Frequency Resp
LF Cut
THD
THD
+ - 0.5 dB 30 Hz to 20 KHz WRT RIAA
-1 dB 25 Hz -3 dB 20 Hz
0.03% at +12 dBmW Out
0.03% at +25 dBmW Out
S/N Ratio
WRT 3.6 mV + 8 dB at 1 KHz
70 dB 20 Hz to 20 KHz
78 dB 400 Hz to 20 KHz
Power
Requirements
Current
+ and – 15V DC +- 20%
40 mA each side
Physical
Size
W 70 mm x L 140 mm x H 25 mm
4
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