Probably not appropriate to talk about this here. I started a thread over at ASR about it though: https://www.audiosciencereview.com/forum/index.php?threads/setting-up-an-active-crossover-using-roon.29882/

Mani.

Happy New Year everyone!

As some of you know, a while ago I switched to a 4-way active setup - 10 amps driving 10 drivers in total (2 subs per channel). Crossovers and delays all performed digitally, feeding an 8-channel DAC.

This hobby is full of trade-offs. Although I maintain that XX is the best playback software in existence, my experience is that it can't compensate for the negative effects of passive crossovers.

The sound I have now is easily the best I've ever achieved in my room. (A couple of members here have heard it, and I'll let them chime in if they wish - although even they haven't heard the latest iteration.) Right now, I'm wanting for nothing. But at the back of my mind, there's something that's still nagging me. Could my 8-channell DAC be improved upon?

There's only one other DAC that I'd consider, were it to exist - an 8- or 10-channel NOS1.

I realise that this is probably just a pipe dream of mine. Judging from the lack of posts on this forum these days, I suspect most people here are quite content with their sound. So, there's probably not a lot of incentive for Peter to even look into creating a multi-channel DAC... especially considering that it wouldn't be compatible with XX. BUT... if one were to ever magically materialise, I'd jump on it.

Cheers everyone and have a great New Year's Eve,
Mani.

No, definitely not... in my case, at least.

I think it depends on the amp, but I have a pair of ultra-quiet fully balanced mono amps in my office. With no input connected, there is slight hissing/buzzing sound with my ear right next to the 97dB/W speakers. However, with the outputs of the NOS1 connected to the amps' inputs, they are dead quiet - absolutely no noise, even with ear right at mouth of high horn or next to mid-driver.

I would recommend that you test for noise with everything connected.

Mani.

David, probably a dumb question on my part...

Are you sure your DC offset is at its minimum? If not, that could be creating noise.

Keep switching #2 off and on until the meters read ~10mV. (One of my NOS1s reads ~15mV, the other ~3mV.)

HTH.

Mani.

Peter, you should unpack it. It's a seriously good-sounding DAC, IMO. To the extent that, for me, it's finally ended the R2R-SDM debate.

Mani.

It appears that the author of the article you attached made some fundamental errors in setup when taking measurements. Corrected measurements (by another person) are shown here:

https://www.amazona.de/community/ueberpruefende-messungen-am-rme-adi-2-pro-fsr/

Mani.

Hi Joachim, it's useful that it has a 12V DC input for power. I use a Paul Hynes linear PSU with mine. I haven't tried the stock SMPS that came with the unit, so don't know how much difference it makes. In my case, I don't have any SMPSs attached to my audio mains circuit and wanted to keep it that way.

I have to say that I continue to be very impressed with its SQ as a DAC.

Mani.

Actually 4x that - it can record at 768, if your recording software can accommodate that.


Hmm... I can't tell - is this a belated 1st of April attempt?


I've had mine since August last year, but hadn't tried it as a DAC in either of my systems until only recently. I bought it primarily for my vinyl digitization project (which never seems to get off the ground), so the RME has remained in my basement 'studio' gathering dust for the most part.

I brought the RME up to my office system when I put the F4 monos in. They have zero gain, and I wanted to hear how they sounded being pushed. My NOS1 (XLR not BNC) was fine for the sort of sound levels I usually go up to in my office, but not for pushing the F4s, so I brought the RME up for its +24dBu output capability. I have to say that I was surprised and impressed with the sound - more dynamic and alive-sounding than the NOS1 when level-matched (by quite a large margin)... in this system at least.


  I was waiting for an announcement from you, but when one never came, I thought I'd announce something of my own.

Mani.

George, you're probably doing this already, but make sure you set your phone to 'flight mode' 

Mani.

The other day I was bored, so I made up a mini-jack to stereo BNC connector. I connected my phone (Samsung Galaxy S10) to my Blaxius^2 cables, pressed play, and... was completely blown away by the sound. The deepest bass, the clearest mids and the most pristine highs I've ever heard.

No more XX or NOS1 for me. It's the phone all the way now.

Mani.

The speakers are spec'd at 97dB/W@1m. The F4 mono needs a 10V swing to achieve its full 100W output into 8 Ohms, but I don't need anywhere near that power in my office. I've been listening at -12dB for most part, and it's about as loud as I would want in my office.

Bear in mind, I'm using a Mach II and Lush^2 in my office. Compared to a Mach III and Lush^3, it's probably not surprising that it's not as exciting a sound as it could be, perhaps.

Still, very, very nice to listen to though.

Mani.

I'd been intrigued by the First Watt F4 amp since it came out quite a while ago now. I say 'amp', but it's actaully a class A 'impedance converter' with no voltage gain or feedback.

With a run of only 100 in total (each assembled by Nelson Pass himself), I never thought I'd get around to ever hearing one, let alone owning one. In NP's own words, "Overall, it is one of the best sounding amplifiers, and if you can live with unity voltage gain in your amplifier, it is possibly your best choice."

So, I jumped at the opportunity last year of buying not one, but two F4s, to use as balanced monos for my office system. But only yesterday did I finally get around to hooking my (non-B75) NOS1 up to them.

So, how does the NOS1 sound driving the speakers pretty much as directly as it's possible to get?

It's a really interesting sound. Zero brightness, with a more 'wooden' (as opposed to 'metallic') sound. No element of the sound brings particular attention to itself. Really beautiful midrange detail though. And totally integrated from top to bottom.

In many ways, a sort of 'boring' sound, because there's not a lot to say about any one aspect of it. And yet, really, really lovely to listen to. It's how I always hoped tubed amps would sound, but never actually did in my experience.

And all this with a 'mere' Lush^2! (Peter, there may be a new order coming your way  .)

Just thought I'd share...

Mani.

Ha! Of course, everything's started working properly again. Even SFS 200 works fine now. I haven't done anything.

I really don't know what caused the error.

All 48GB is detected...

Thanks Peter.

It's the Mach III. Yes, I will swap the memory from the Mach II if I have to.

Max SFS has always been set to 24.00. I've just brought it down to 4.00 and set SFS to 1.00. Playback bow works again 

I usually keep SFS<2.00 anyway, so as long this continues to work, I should be OK. The only issue I might run into is playing MQA files... but I very rarely do this anyway.

Strange that this has started to happen all of a sudden...

Mani.