Making Vinyl a Superior Playback Partner
The PS Audio NuWave Phono Converter – or NPC for short – is a stunning analog phono stage. But the future of audio is more than just turntables and vinyl. So PS Engineering added a state of the art A/D converter right into the NPC phono, accepting inputs from any analog source from tuners to turntables.
With the NPC it is now possible to keep a high-end DAC as the heart of your system and play vinyl as well as any analog source without compromise. Or, if you prefer, you can place the NPC in an all analog system and use its digital feature set just to record and catalog your vinyl. The NPC is right at home in either setup, analog or digital.
And the NPC is ready for the future with a high resolution DSD, PCM and analog engines built in.
"A Real Pleasure to Review!"
"PS Audio's NuWave Phono Converter is truly an innovative product with great sound and value for the money," reports Anthony Cordesman in The Absolute Sound magazine, February 202, 2014. "A real pleasure to review – even if it does suck me into making digital copies of my LPs!"
In his November 22, 2013 post for DigitalAudioReview.net, John H. Darko asks, "Was the NPC's digitised take on an LP indistinguishable from the original?... If there were sonic differences, I couldn't pick 'em." He concludes, "A round of applause goes out to Paul McGowan and his team for bridging the vinyl island to the digital mainland."
Fully Separate Analog/Digital Paths
Unique to the NPC is PS Audio's design philosophy of isolating and separating the analog and digital paths within the device. This means that the phono preamplifier built into the NPC is a balanced, class A phono stage from input to output.
The general trend in A/D converter based phono stages tends to be a hybrid of an input analog step-up stage feeding an internal A/D converter where the RIAA EQ curve (required for vinyl) filtering and further amplification are all handled in the digital domain. PS Audio's philosophy was quite the opposite: keep the vinyl amplification chain, including the RIAA curve, completely analog from input to output, the way LP's were intended to be reproduced.
The NPC then channels that high level signal to its state-of-the-art A/D converter for digital processing. This ensures that vinyl amplification, EQ and filtering are all handled as they were designed to be and the resulting sound is sweet and open without any digital artifacts or issues to contend with.
High Resolution Reclocked DSD and PCM
If you choose the digital path for your analog inputs, it is not only possible, but actually amazingly good to simply play vinyl LP's and analog sources of all kinds directly through your system's DAC. For the first time, a high-end turntable or tuner setup is just another input on your D to A converter and you'll be amazed at how great this sounds.
You can choose any sample rate from 44.1kHz all the way up to 192kHz and select any bit depth from 16 to 24 bits for playback or recording using the standard digital audio PCM. You can also choose DSD (Direct Stream Digital), which is a more analog-like digital audio format used on SACD recordings. Here you can choose from standard or double rate DSD and play directly into any DSD capable DAC or through USB into a computer for recording purposes.
The Parallel Digital Path
The heart of the NPC's design philosophy is running parallel and separate analog and digital paths, allowing each to be fully optimized for best performance. Vinyl mastering is handled through filters and reverse RIAA EQ kept strictly in the analog domain from the input to the final output of the cutting lathe.
Once the playback and EQ requirements of the vinyl path have been properly amplified, it is now a relatively straightforward process to quantize (make digital) the output through a state-of-the-art Analog to Digital Converter (A/D Converter).
This technique is really the secret to the NPC's success. You can plug the output of your DAC (with its input fed from the NPC) into one analog input on your preamplifier, and the pure analog output of the NPC into another preamplifier input and switch between the two while you're playing a record. Depending on the quality of your DAC, there will be little to no difference between the sound of the two. With an analog to digital converter of this quality, it's easy to commit your entire analog collection to a hard drive for archivist quality reproduction.
Using appropriate software on a PC, NPC owners can RIP their entire vinyl collections to their computers at 192/24 PCM or DSD and stream the high resolution files to their loudspeakers at the touch of a button.
Reclocked 192/24 as well as 64X and 128X DSD can be sent over S/PDIF through either the USB or coaxial output and a direct DSD and PCM streams are available through the I2S output. Use of the DoP protocols are standard on the NPC.
Plenty of Gain for Plenty of Cartridges
Phono cartridges the NPC will work with range from a high output moving magnet or ceramic with up to 220mv output, to a delicate low output moving coil cartridge with as low as 0.3mv out. This is an extremely useful range of outputs that can be selected from the front panel display in 3dB increments. Full resistive cartridge loading options are available on the rear panel.
Many competitive designs rely on feedback based RIAA curves, but these can have the disadvantage of uneven gain products throughout the audible spectrum and the end result is a different sonic character for all frequency bands – a problem solved with the NPC's use of passive EQ. Using a passive network sandwiched between two linear gain stages provides EQ accuracy of 1/10th of a dB from 20Hz to 20kHz.
Differential, Discrete, and FET
The analog phono preamplifier's two main gain stages consist of a differential low noise preamplifier input stage coupled through the passive RIAA into a discrete class A FET output stage.
The phono preamplifier's input differential gain stage is a beautifully designed programmable low-noise gain stage from THAT corporation. THAT 1583 is a major breakthrough in performance with 60dB of programmable gain and noise specified at an incredibly low 1.9nV/√Hz and wide bandwidth to well over 1mHz. This stage forms the interface gain device between the phono cartridge and the NPC and its output feeds our passive RIAA curve.
Following the EQ stage is a new class A all FET discrete gain block. This stage features a combination of JFET and MOSFET devices in a low open loop design that brings a rich, luscious and open path for music on your vinyl discs.
The All Important A/D Converter
To handle the critical duties of converting the final analog output to digital audio for playback on your DAC or recording on your computer, PS Audio chose an excellent product from Burr Brown, the PCM4222. This high-performance A/D converter features dynamic range, low noise, and distortion characteristics that exceed 120dB.
For PCM the NPC gives a full 24 bit 192kHz output while the DSD option handles 64X or double DSD at 128X oversampled rates. The NPC then takes the output of the PCM4222 and run it through PS Audio's Digital Lens reclocking solution to make sure the clock that drives the A/D is isolated from the clock that outputs the actual data. This removes any chance of added jitter to the output digital audio signal.
Both PCM and DSD can be sent over S/PDIF, I2S, or USB using the DoP (DSD Over PCM) protocols that are standard in the industry. S/PDIF and I2S are used to feed any DAC you might have regardless of its input capabilities. If you have an older DAC that only handles, perhaps, 96kHz 24 bit PCM, it's no problem you simply set the front panel of the NPC to match your DAC's limitations or potential. If your DAC accepts DSD that will travel properly over the S/PDIF format and work great.
Digital outputs to feed your DAC, soundcard on a computer, mixing console or recording control board on the NPC are available through the HDMI connector (I2S) or coax (S/PDIF). USB can be used not to feed your DAC, but to feed your computer.
Feeding Your Computer
If you wish to record analog sources from the NPC such as a, turntable, tuner, microphone or recording console output, it is a fairly easy and straightforward process. Simply connect through USB and the reclocked output will connect right up to your computer. You can record either DSD or PCM through either Mac or Windows machines using an off-the-shelf program such as Audacity.
Because DSD is sent using what is known as DoP, Audacity or other recording programs handle the files as if they were standard digital audio WAV files. DoP does not alter the DSD data in any way other than cutting it up into acceptable packets that look like PCM, but of course are not. The pure DSD stream is maintained perfectly for future playback.
When it comes time to playing back your recorded files, you can use any number of DAC's that can stream from a computer (like PS Audio's PWD/Bridge for PCM) or you can play the files directly on your computer using a program like Foobar for Windows OS and Pure Music for the Mac operating system.
This setup allow you to stream either DSD or PCM directly to your DAC or to your computer for storage. It's easy, simple and rewarding to begin to build a digital audio library of all your analog based source material with the NPC from PS Audio.
"PS Audio's NuWave Phono Converter is truly an innovative product with great sound and value for the money. A real pleasure to review – even if it does suck me into making digital copies of my LPs!"
- Anthony Cordesman, The Absolute Sound magazine, February 20, 2014
"The question barked loud: was the NPC's digitised take on an LP indistinguishable from the original?"
"I ran a real-time digital vs. vinyl stand-off using Vinnie Rossi's Red Wine Audio Signature 57: the analogue output of the PS Audio NPC fed into one input of the integrated, the analogue output of the INVICTA Mirus into another. The Mirus was carrying a 24bit/96kHz real-time encode of vinyl playback that showed no time lag."
"If there were sonic differences, I couldn't pick 'em."
"A round of applause goes out to Paul McGowan and his team for bridging the vinyl island to the digital mainland."
- John H. Darko, DigitalAudioReview.net, November 22, 2013