Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion HiFi & HT Chat Upsampling and skinning the proverbial cat

I've been playing around with the Sooloos and adapting to its interface and sound. The upsampling option has been causing some paranoia as I prefer the presentation of 16/44 CD files without the upsampling selected.

However, I understand that technically this is less favourable at the SPDIF output. Fellow HH's have suggested the ID40 / 808.3 route to a higher quality but I'm loathed to pay for something that I wouldn't use (the CD and analogue pre)

So... I started reading. To quote from a post on Computer Audiophile by Steve from Empirical Audio:

"The difference is the upsampling algorithms. When hardware is designed to upsample audio streams on the fly, there have to be compromises in order to fit the logic in the chip and do the upsampling in real-time. There is also the issue of talent of the designer in selecting the best algorithms, filtering and dithering.

Software upsamplers on the other hand have no real time constraints or hardware fit constraints, so the designers can use more complicated algorithms that cannot currently run real-time. These can be more accurate and get closer to the ideal hi-res master.

Having used a number of upsamplers and modded more than a dozen DACs in the last 10 years, I have concluded that there are no really good hardware upsamplers, and the software upsamplers that are world-class you can count on one hand. Even with these, the settings for pre-ring and other options are critical to getting a good result."

One of the computer software packages that comes very highly recommended is Wave Editor from Audiofile Engineering. Unfortunately it's only available on the Mac... (hence a MAC MINI in the post as we speak...)

I was considering the Weiss Saracon package until I discovered that it looses all the metadata on conversion which all has to be manually re-entered... (yes, my thoughts too!!)

My intention is to dither/upsample my "chill out" tracks and thus avoid the unfavourable environment inside the Control 15. Of the stored albums I have there are 30 or so that I listen to intensely so I intend to start with these. Others for the Mrs and the kids (Now that's what I call music etc) can stay as 16/44 tracks to save hard drive space and my sanity.

One day if Meridian allow the Sooloos to output at 24/192 then I'll have the tracks to do again, but hopefully by then they'll be economically viable 2TB 2.5" SATA hard drives to retrofit to the Control 15... and pigs might fly!!

Has anyone else gone down this route, or got experience of the Wave software with preferred settings I'd be very interested...

PS No cats will be harmed in the dithering process...

Dpaws, did you try out the MS600 as a more cost effective alternative to the 808.3/ID40?

The 808.2 and onwards just commands respect, I've had the Weiss Minerva in the system, but the 808.2/808.3 is just how it's done.

I hope to assemble my theater in the next few weeks or so. I might just try the MC200/MS600 out even though the space issue is still in the air regarding standardised support for NAS filers, but still I wonder can the MS600 really be close to the 808.3/ID40..? Or will it still sound "G" level?

I've compared Audiofile's Sample Manager that uses iZotope's routines for sample rate interpolation and dither. There are various setting options to customize the filter characteristics to optimize for time or frequency domain to achieve a subjective preferred compromise. I've also used other software based "real time" sample interpolation with options for time or frequency optimization. Given the limits of M gear I've compared 44.1 source interpolated to 88.2 files and/or real time software interpolation.

So far my subjective preference with M gear using an audio optimized Mac is audio rendering software that operates in integer output mode with original 44.1Khz source. I use an async USB-SPDIF bridge to feed M gear and prefer M's apodizing version of the software to the earlier non apodizing software. YMMV.

Avi

Thanks Crion,

I'm yet to be convinced that the MS600 performed at a significantly higher level than the Control 15, particularly as a common DSP chipset is used. In terms of economies the new minimac and Wave software package stand me at �600 - about a third of a MS600 yet I have infinite variations and flexibility with the upsampling.

If someone manages to clone the Sooloos user interface then I may simply at a 23" touch screen monitor and utilise the firewire output into the M2 (internal mod)

"I've had the Weiss Minerva in the system, but the 808.2/808.3 is just how it's done"

It's a shame you didn't try the Weiss Medea, the statement DAC from Weiss - its Class A output stage is so robust I drove my Feastrex open baffles directly from the XLR outs! It's a matter of taste, and my preferences are for the more honest and energetic NAIM/Weiss sound than Meridians "merlot" tinted presentation.

(I seem not to be alone, a noted reviewer swapped out his 808.3 first for a NAIM setup and then for a dCs rig...)


Hi Avi - "I've compared Audiofile's Sample Manager that uses iZotope's routines for sample rate interpolation and dither"

Yes, it's iZotope's routines that have been so strongly recommended and are behind the choice. I'll let you know if I discover the integer mode setting... I'm sure with so many setting options available it'll drive me nuts trying to decide the best combination...

Some have noted that a DAC will tend to have an optimum sample rate - but my system doesn't contain a DAC so it's all fresh ground... fingers crossed

Much obliged, Steve

Integer output mode will depend on the rendering software (and options i.e. DSP), OS version, DAC and interface type i.e. USB. AFAIK Audiofile's audio rendering product Fidelia doesn't support integer mode output.

Having compared many of the Mac software audio rendering products that are apparently bit perfect (assuming no DSP is applied) I was surprised by their different sonic signatures.

Avi

Dpaws, I didn't try the Medea in my own system as I was only running the Minerva as a Firewire->SPDIF soundcard into my Meridian system and it was only later that the Medea got the Medea+ with firewire input (and revised analog section) available now.

The funny thing is though that the "forward" presentation of the Weiss Minerva "Soundcard" configuration actually survived into my full DSP Meridian system. I really enjoyed it but there was a slight sibilance (perhaps a bit strong word for it) in the top that was the only gripe I had with it. That same emphasis was there in the Jason-Medea combo in the store with a completely different setup so I attribute it to the Weiss sound.

Now when listening to the 808.2 it just sounds right to me and maybe they have Merlot it a bit I can't argue for/against it. But I hold it the closest to what I think it should sound like at the moment. Maybe the truth is somewhere in between(?) YMMV.

" But I hold it the closest to what I think it should sound like at the moment. Maybe the truth is somewhere in between(?)"

I guess that's what hi-fi's all about - if you find a sound you love, stick with it and enjoy. Having heard the affect of different recording mikes, cables, A/D converters and mastering there's really no "truth" as such, all variations on a theme of truth.

"there was a slight sibilance" Having heard the Jason/Medea combo its about as honest (and ruthless) as it gets - superb kit but shows up any errors in the recording. If M's presentation makes that recording enjoyable again then it's hard to argue that's wrong...

What a wonderful yet bonkers hobby!!

Avii - are you using the Halide Bridge as the async USB-SPDIF connection? And if you are, do you think it's a worthwhile improvement?

Cheers ....... Kent

Yes it's a Halide Design.

I prefer the results compared to using Toslink or HDMI via the HD621. The Bridge also supports non mix integer mode that is an option offered by some Mac audio rendering software. The latter avoids some additional processing/conversion steps and to my ears makes a noticeable difference. YMMV.

Avii

Avii
Is it Pure Music or Amarra that you are using??

Have you tried the Integer 64bit Upsampling in v1.8 of Pure Music and what did you think???

Have you tried any of the other Audio Plug Ins supported by Pure Music????

Thanks

I'm currently using PM (1.8a) and Audirvana (0.9.4). Although I have Fidelia, Amarra and Decibel non of these currently supports integer output AFAIK. Interestingly they can all sound different to some degree even without DSP being applied.

According to the last info I have from Rob at Channel D non mix integer mode precludes any DSP including upsampling -

"Upsampling isn�t available with integer for good reason.

The digital filtering required for upsampling (upsampling involves much more than just inserting samples) is done with 64 bit floating point math."

I have compared integer mode with the non integer upsampling options and prefer integer. YMMV

I haven't tried any other plugins at this stage. One concern/goal I have is minimize Mac processing activity that may have an impact on audio. Currently activity monitor averages PM and Audirvana at a steady 98%-98.75% idle during playback.

Avii

Interesting. I called a friend today and told him I was going to give the Halide Design a shot based on Ronnies posts and followed by some research on my part. My friend seemed to believe I should just go the optical route. He has the optical cables and will bring them over this weekend as I will finally make it back to Vegas. What would you say is the Toslink's greatest weakness?

Gary