mrporcelain Posted August 13, 2014 Posted August 13, 2014 Item: Symfonia Opus 8 preamp and PSL-1 power supplyLocation: Melbourne Price: $700Item Condition: Excellent Reason for selling: No longer used Payment Method: Pickup - Cash bank depositExtra Info: More info below. What you get is the preamp, power supply, original box and manual. The preamp is an amazing neutral pre, the build quality is phenomenal, it uses penny and giles controls (the volume control cost $600 when it was built) and even the power supply has a 1cm thick aluminium fascia and weighs 6kgs. It's an excellent performer and for this price an absolute steal, I've dropped the price as I'm sick of looking at the boxes. Comes with original boxes and manuals. Pictures: Design Goals All preamplifiers provide volume control together with source selection. There are many different techniques available to realise these functions. At Symfonia, we embarked on an exhaustive search to find the best components available, coupling them with advanced 'state of the art' design techniques. Volume Control A precision volume control system incorporates the following attributes: Accurate channel "tracking"; a measure of how well the left and right channels follow each other as the volume control is changed. Low Distortion. A high degree of isolation between channels, even at high frequencies. Long life. Infinite resolution allowing perfect setting of the desired level. Some types of volume controls use rotary switches or miniature relays with resistors. Although this provides good tracking and low distortion, the number of steps are limited, As a result, the "smoothness" oresolution of the volume control is reduced. The only volume control that fulfils all of the above requirements is a rotary fader manufactured by the Penny and Giles company. Source And Record Selection The best type of input selector is none at all. For this reason, we designed the Symfonia Reference SR-1 Line stage. However, as many systems employ more than one source, we embarked upon a multi input design that utilises the best source selection technique available. Our primary concern in implementing source selection was the preservation of the inputs' signal to noise ratio. Degradation of the signal to noise ratio occurs when low level audio signals are routed to front panel selection switches. Therefore, we have realised all switching through the use of precision miniature relays mounted on the back panel. This minimises the length of the signal path thereby ensuring a high signal to noise ratio. The front panel switches merely operate the respective relay connected to the source by means of a noise free DC voltage. Two independent switch blocks have been implemented to allow the user to listen to one source while recording another. Power Supply At Symfonia, we have long recognised how the performance of the power supply can adversely affect the sound quality of audio equipment. Therefore the power supply has been located in a separate enclosure so that it can be placed well away from the sensitive electronics inside the preamplifier. This physical separation allows us to use large transformers in the power supply achieving a very low power supply impedance. We manufacture two different power supplies that are suitable for the OPUS 8 preamplifier. The model PSL-5 Power Supply consists of a custom made 80 VA toroidal transformer, fast recovery diodes and 16,000 uF of low Equivalent Series Resistance filter capacitors. A more highly powered model, the PSL-1 Power Supply, consists of a custom 300 VA toroidal transformer, integrated RFI filtering, and a massive 96,000uF of low ESR filter capacitors. Inside the preamplifier each channel is equipped with a further 24,000uF of low ESR filter capacitors, generously bypassed with multiple polypropylene capacitors on the main circuit board. Furthermore, four high performance power regulators are provided for each channel. The result of this exceptionally pure power supply is outstanding sonic performance. Active Circuitry A great deal of research has been undertaken into the performance aspects of audio amplification. A major outcome of this work is the way in which capacitors in the signal path have been shown to adversely affect the sound quality of preamplifiers. Capacitors exhibit a phenomenon referred to as "Dielectric Absorption". Some manufacturers address this problem by choosing capacitors with exotic dielectric materials such as Teflon. Although these materials do perform better than standard dielectrics, we consider that the complete elimination of capacitors in the signal path results in a superior sounding product. As a result of removing all capacitors from the signal path, the amplifier is capable of amplifying down to DC. This places stringent demands on the stability of the active circuitry as any DC offset introduced by the source or the preamplifier will be amplified along with the signal and appear at the output of the preamplifier. These problems have been addressed through use of dual monolithic FETS fabricated on a common substrate to achieve perfect matching. This technique reduces the input offset voltage due to the preamplifier to vanashingly low levels. Together with active servo circuitry which monitors any DC voltage present at the output, an equal and opposite voltage is generated to precisely maintain the output at a zero volt reference. A mix of FET and Bipolar technology is utilised in a "Cascode" circuit topology to achieve low distortion under high voltage swings. Combined with a pure Class-A output stage running at a high idling current, the preamplifier is able to drive long runs of interconnect cable plus the input circuitry of the power amplifier with ease. Construction All Symfonia products are individually crafted to our strict manufacturing and design standards. The OPUS 8 is no exception and has been built to last a lifetime. Mechanically, the preamplifier is built around a rigid chassis. The front panel is milled from a single piece of 12mm aluminium whilst all lettering is meticulously engraved and lacquer filled. The whole unit is then hand finished with a warm lustre of brushed aluminium. The OPUS 8 follows in the tradition of our other fine products - Only the finest components from the most reputable manufacturers are used Generous design allowances have been made to protect against environmental and operational extremes. Consequently we are proud to offer a comprehensive five year warranty. Finally... There is only one superlative to describe the sound of the OPUS 8. Accuracy, simply stated it neither adds or subtracts from the original. Superbly constructed it achieves the ideal - a piece of wire with gain. If you are in the market for a fine preamplifier then the Symfonia OPUS 8 must be considered. Audition it now at your nearest Symfonia dealer. Or email us if you require further information. Specifications Frequency response.Between 1 Hz and 200 Khz 3dB points Signal to Noise Ratio -95dB A weighted Channel Seperation 86 dB at 1 kHz Maximum Ouput Voltage 13 volts RMS Input Impedance 10k ohm Output Impedance 50 ohms Total Harmonic Distortion less than .001% Dimensions Height 74 mm Width 482 mm Depth 380 mm Net Weight 6 Kg PSL-1 Power Supply DimensionsW 255 mm D 280 mm H 85 mm Weight Nett6.0kg each 1
PicoWattson Posted August 13, 2014 Posted August 13, 2014 Magnificent piece of engineering by Vince Testa and Stan Berkeley from the mid nineties, probably performs better than many produced today. Looks in great nick cosmetically and definitely worth fettling back to prime condition. Wish I still had mine.
mrporcelain Posted August 14, 2014 Author Posted August 14, 2014 Interested party pulled out so back up for sale.
mrporcelain Posted August 25, 2014 Author Posted August 25, 2014 I can also post this. Contact me for a quote.
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