Applying convolution filters to vinyl playback

Hello, crowd. My preamp processor, a Marantz 7702, has Audyssey MultiXT32 sound correction within. However, I have found that by working with Thierry of Home Audio Fidelity and @Mitch_Barnett, the sound in my system can be improved by using convolution filters developed for Roon.

Since Audyssey is already converting the analog signal from my phono preamp to digital anyway, I am now wondering if there is a way to apply the convolution filters in Roon to an analog-converted stream. I have a Benchmark ADC1 analog to digital converter and a Lynx AES16e soundcard.

Is there a way to create a stream in Roon that would play out the digitally converted vinyl on a real-time basis for whatever particular album is being spun on the turntable? Obviously, Roon won’t report metadata, but I am not concerned about that.

Thoughts? JCR

Have look here: Can a local server stream FLAC to Roon?

Thank you, @anon47919701. Very good tutorial on how to do it at the link you provide, complicated though it may be to set up. Does anyone know if Icecast and Liquidsoap pass the data through on a bit-perfect basis? JCR

Wouldn’t another option be to capture your records to digital and play back the files? You lose the tactile feeling of playing records, but it might be a whole lot easier.

Hi @Neil_Bulk. Understood, although then I either need to digitize my entire vinyl library or limit my vinyl listening only to those select albums that I have specifically gotten around to digitizing and saving to my network attached storage system. So, for greatest ease of use and flexibility, I like the real-time approach linked above, albeit I would first like to know if anyone can confirm the bitperfect stream as a result. Thanks. JCR

Oh I never said it would be easy. :slight_smile:

@qdtjni, asking you to join in here, as it is your thread that describes using Icecast2 and Liquidsoap to stream digitized vinyl on the fly. My question is whether this is bitperfect if, for example, I digitized the vinyl stream at 24/192. Thanks. JCR

IIRC, there’s a step where the word length is truncated to 16 bit if the ADC converts is using anything higher than 16 bits.

Given that the theoretical 96 dB provisions ones by 16 bits is more than enough for vinyl, that should not affect sound quality. However, the true sense of bit perfect, it is not.

All current methods to do this are flawed. The only way to get a stream into Roon from Vinyl is to use an ADC, to feed into internet radio encoding software such as liquid soap, rocket broadcaster ets and the an internet radio server software such as icecast. Then Roon can pick it up as flac radio stream. Whilst it works the encoder side on all os platforms is a big weak leak and none currently do 24bit with a high sample rate which you want if you want DSP. The best your can get is 16bit. Recent liquidsoap versions support ffmpeg for encoding so may achieve 24bit but building a version for your distro is not fun or simple. I have now given up on this as a way to get it in to Roon. Also the latency is really bad especially via icecast and if using a raspberry pi your looking at 10seconds.

Nope the liquidsoap encoder will only do 16 bit. Newer versions from 1.4 support encoding via ffmpeg but I doubt you will find it prebuilt for your distro so you have to build it yourself from source.