Metrum Pavane

[kvik]

Ny top-DAC fra Metrum Acoustics, Pavane, til €5000 (intro €4500) - R2R, NOS, egenudviklet chip, ekstrem liniaritet, samme ind- og udgange som Hex, full-size kabinet.






Working principle: Non oversampling dac. Forward (FPGA) corrected, 4 Dacs pro channel in differential mode.

Power: 45 VA via 3 separated torodial transformers.

Mains voltage: 110/115V AC 220/230V AC 60/50Hz

Inputs: 1x optical, 2x coaxial (1x BNC and 1x RCA). AES/EBU and USB

Outputs: 2x RCA Neutrik © cinch connectors. 2x XLR balanced output.

Output voltages: RCA : 2 Volts RMS. XLR: 4 Volts RMS

Frequency responce: 1Hz - 20 khz -2.5 dB. 44.1 kHz sampling. 1Hz - 65 kHz - 3dB .192 and 384kHz (USB)

Distortion: 0,008 % THD

Noise: -145 dB t.o.v. 2 Volt RMS

Output impedance: RCA 100 Ohm. XLR 200 Ohm

Sampling rate: Optical 44 - 96 kHz. Coax and AES/EBU 44 -192 kHz . USB 44 - 384kHz

Dimensions: 440 x 320 x 85 mm.

Weight: 9000 grams.

[kvik]

Første test-omtale af Pavane
http://the-ear.net/review-hardware/metr ... verter-dac

Med nedenstående forklaring på dac'ens virkemåde (forstå det, den som kan )
The Pavane is the result of fresh thinking and an awful lot of testing and listening to what is called a FPGA/DSP “forward correction module” and transient converters. What goes on inside the converter is not easy to explain, but I will give it a try. The signal coming in from the S/PDIF (RCA or XLR), optical or USB input is converted into an I2S stream. The I2S data is fed into the FPGA and split into two new formats, both I2S. These data streams are manipulated in the FPGA in such a way that when they reach the transient converter chips as two separate balanced clusters for each channel, the converters will interpret the data in such a way that they always use the highest segment of the ladder converters inside the transient modules. Put in other words, the MSB (most significant bits) and the LSB (least significant bits) are both marked as MSB and use the top 24 resistors inside the R2R converter. The analogue output parts of both streams are now at the same level, which is of course not what we want, the original LSB stream should be about -60dB in level. The final step in the process is summing the two analogue signals and restoring them to the original levels. The crossover point is not strictly defined and the splitting up of 24 bits into 2 x 12 bits is impossible to explain simply, but it might give you some idea what goes on inside the Pavane. But why manipulate the data stream? Well, whatever R2R converter is used, problems always arise with the LSB part, because of the signal is smaller and at a lower level irregularities occur, non-linearity arises and digital noise becomes part of the analogue signal. In the Pavane these nasty side effects are damped by -140 dB or more. They will never be part of the analogue music signal. Now this looks simple on paper, but it took about a year to write the algorithms for the FPGA, develop the transient R2R converters and start up production.

[sorenb]

man kan jo osse spørge sig selv hvor mange indspilninger man der har et dynamikområde større end 72db? .... nok ikke ret mange ... og hvorfor så bekymre sig om at tage de mindst betydende 72db og pudse dem af i alle ender og kanter, for så at 'skubbe' dem ind under de øverste 72db? Det er helt sikkert ret besværligt at få det til at fungere - ligesom det er besværligt og uden mening at pudse sine sko under neden ...
Den lyder sikkeret fint, osse selvom det i.flg. review'et altid skal stå tændt, men mon ikke det er fordi udviklingen af den såkaldte "Transient R2R converter" mestendels bestod i at beherske smergellærredet så Wolfson logo'et kunne blive FPGA'et og danne 'sort' baggrund for det flotte "Transient"

[Claus-DK]

Den ser godt nok lækker ud både inde og ude..

[Sebastian L]

Ny top-DAC fra Metrum Acoustics, Pavane, til €5000 (intro €4500) - R2R, NOS, egenudviklet chip, ekstrem liniaritet, samme ind- og udgange som Hex, full-size kabinet.

Lige en korrektion: R2R betyder netop, at man benytter en såkaldt "ladder" af modstande. Så der er altså ikke tale om nogen "chip", hvilket er det specielle ved konstruktionen. IMO klart at foretrække fremfor en industrifremstillet DAC chip.

[kvik]

Fra deres hjemmeside:

"With that goal of creating a very special DAC in mind the designer, Cees Ruijtenberg, has during the past year developed a new DAC.

It was an unprecedented challenge, which was eventually solved by introducing an entirely new chip, which has been exclusively developed by Metrum Acoustics"


Men, jeg forstår din pointe.

[toppe]

Så vidt jeg ved findes/fandtes der flere R2R dac chips, fx PCM1704? Er jeg helt skævt på den?