I've been working on this project for a while now. My goal was to integrate a good Turntable into a fully digital system. This thread will serve two purposes. First, I want to inspire others to this as well; misery loves company. Secondly, I want to describe in detail how I am "streaming vinyl."
Many folks are ripping vinyl. I understand the many benefits to ripping vinyl from a convenience standpoint. I guess I am too impatient to wait to hear the music. Oh, and did I mention the "ritual." The setup is very simple: Convert the vinyl from the Luxman PD-171AS turntable, Jelco 750 arm and Soundsmith MIMC cartridge using a high quality AtoD converter, process digitally and send back out to the same high quality DtoA converter. Of course, I need to amplify the TT output before the AtoD. For this, I do NOT use any analog EQ for RIAA. I use a pair of mono Earthworks ZDT 1021 mic preamps. The mic pres are consider by many to be the lowest noise and "cleanest" mic pres available. They can add up 60db of gain. They are direct coupled, balanced end-to-end and have no resistors or op amps anywhere in the signal path. All RIAA is done in the digital domain in this setup. For this, I use Audiolense to generate excellecent RIAA filters. Here's what they look like:
There are several advantages to doing EQ in the digital domain. The precision is greater in the digital domain and the the resolution is also better than any sanely prices phono preamp. The frequency and phase can easily be independently manipulated using high precision FIR filters. All digital processing is done at 64 bit floating pointing, so there's a clear advantage to doing this in the digital domain.
The digitized vinyl is sent into the ASIO line-in for Jriver. It is then processed through the Jriver convolution engine which applies all my digital filters.
Once the vinyl is in the digital domain, I can also use high quality target based DSP. I also use Audiolense for this. You can see my preferred target curve here:
I am not going to post any REW measurement in this thread since I've done that elsewhere. My system is very accurate and the listening position music very closely matches this target curve for both channels.
The digital domain also offer THE BEST method for integrating subwoofers. I am a big believer in using subs in all 2CH systems. IME, I've never heard a pair a passive speakers which could match the ultimate dynamic range of 2CH system using properly integrated subs. The dynamics are truly hi-rez. Subs also offer the ability to get much smoother bass. I've done a lot of testing in my room using various 2 sub setups. IME, Floyd Toole's recommendation to use 2 subs on the frontwall, placed one quarter width each in mono, will give the BEST measured performance in both time and frequency. In my system, my speakers are crossed over using the Audiolense custom crossover at 80hz. This crossover is very similar to an NT crossover. It is phase coherent and totally inaudible. Bass sounds the way it was intended; very fast, full and natural. There are no downsides to using this setup and the upside is never heard before bass.
So, why vinyl? Why not just do all of this digital stuff on a digital file without converting it from analog? The answer has to do with my firmly held belief that many LPs offer superior mastering and transfer compared to their digital counterparts. I have no idea why this is the case and I think it varies depending on the recording. But it's clear that many LPs have superior dynamic range to their digital counterparts. I am not talking about the DR inherent in the specs for a TT vs. a DAC. I am referring to the music itself. The spec which matter most is the music, after all.
What does it all sound like? Well, I am learning about LPs as I go. I am new to all of this. The best LPs I've heard in this system sound like the best vinyl I've heard. It retains that organic vinyl sound; the huge 3D soundstage, the front to back imaging is very extended and the stereo image is non-fatiguing. The surface noise is minimal and far less a distraction than I feared it would be. For a good LP, I would have to turn the volume up close to max to clearly hear any surface noise. The sound is very clean and low noise.
I'll post some more pictures as well as a quicky video I shot which shows the basic setup and connections.