Press Release Summary:
Model 403 Stereo RIAA Phono Preamp drives sound card's line-input for restoring vinyl LP records which were recorded using RIAA equalization. Preamp uses low-noise opamps and features very low output noise and power line hum pickup. Internal rechargeable batteries provide complete isolation from power mains and cast aluminum enclosure minimizes pickup of unwanted interference.
Original Press Release:
Model 403 Stereo RIAA Phono Preamp from TDL® Technology
TDL® Technology, Inc. announces their Model 403, Stereo RIAA Phono Preamp especially designed to drive a sound card's line-input for restoring vinyl LP records which were recorded using RIAA equalization. The preamp uses low-noise opamps and features very low output noise and very low power line hum pickup. When used with a high-quality direct drive turntable, this preamp will readily produce CD-quality wave files with little software editing. The internal rechargeable batteries provide complete isolation from the power mains and the cast aluminum enclosure minimizes the pickup of unwanted interference.
Single quantity price is $189. USD plus shipping. Availability is stock to four weeks. A full data sheet and User Guide in PDF format can be downloaded from our web site at zianet.com/tdl.
STEREO RIAA PHOTO PREAMP
Original version August 2002
This preamplifier was especially disigned to drive a computer
sound card's line-input for restoring vinyl LP records which
were recorded using RIAA equalization. This preamp has very
low output noise and very low power line hum pickup, two
features essential to creating a CD-quality wave file. The
internal rechargeable batteries provide complete isolation
from the power mains during operation. The cast aluminum
enclosure minimizes the pickup of unwanted signals.
INPUT: Matches all common magnetic pickup cartridges. (The input resistance is 47K.)
GAIN: Zero to about 46 dB at 30 to 35 Hz using the single-turn audio taper gain control.
RESPONSE: Playback RIAA as shown in Figure 1. The rumble filters, which may be switched in and out, have corner frequencies of 20 Hz and change the response as shown. Because this preamp was designed to drive a sound card, it includes output lowpass filters with corner frequencies of 25 kHz. This causes no loss of quality because the CD sampling rate of 44.1 kHz limits the unaliased frequency response to 22 kHz.
DYNAMNC RANGE:. Refer to Figure 2. This is a spectrogram of a typical channel with the gain set to 35 dB (the level at which we made our LP record to hard drive transfers) and the turntable motor running. The noise level is 80 dB below the sound card max input and the 60 Hz hum is down nearly 60 dB -- it is not audible in the recorded wave file. Depending on brand, age and condition, vinyl LP records have a dynamic range of 50 to 60 dB
so with this preamp you can "capture" everything that's on the record.
CONNECTORS: Two female, panel mount RCA input connectors. Two female, panel mount RCA connectors plus a 1/4 inch stereo phone jack for output. There is a 5-way binding post near the input connectors for connecting the preamp enclosure to the turntable frame as this may help reduce hum pickup (see the Operation section in the User Guide for more information on hum reduction). 2.5 mm male input power connector for the internal battery charger. A red LED lights when the charging voltage is on.
POWER: Two internal 9 volt rechargeable NiCd batteries provide 12 hours of operation from a full charge. The 24 VDC charger plugs into any (US) standard 115 VAC, 60 Hz outlet. (Power supplies for other mains voltages and outlets available on special order.) The charger is a constant current supply and can be left on to trickle change the batteries all the time the preamp is not in use.
FURNISHED ACCESSORIES: 24 VDC wall power supply and Printed User Guide. The User Guide in .pdf format may also be downloaded from our web site.
PHYSICAL: Cast aluminum enclosure measuring 190 x 135 x 63 mm (7.6 x 5.4 x 2.5 inches) overall including connectors and knobs. Weight is 675 gm (24 ounces) with batteries installed. There are rubber bumpers on the four corners of the enclosure bottom.
PRICE: $ 189.00 (USD) plus shipping.