I suppose Naim is already designing/choosing/outsourcing its future DAC architecture. Do you think they’ll use a “classic” architecture or something built around an FPGA?
I’m a little out of touch here - Simon is a bit more up to date I think - it’s my understanding that all the TI chips are in a cupboard to ensure longevity of the ND555, and presumably the other new platform ND players.
If we assume for a moment that a 272 replacement is coming, and if no TI chips are available, it would have to use something different, so maybe that will show the way, and maybe explain the delay. But I’m as technical as a dishcloth so may be talking rubbish.
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Hi Thomas, it depends what you mean by the classic architecture… if you mean whether they continue to use SHARC processors as opposed to an alternate DIY approach using an FPGA processor… I suspect possibly so… if the latest SHARC processors are exceedingly low power and support large kernel size FIR filter response kernels then it would appear a sensible approach to try… if Naim run out of SQ runway with the AD SHARC devices and decide to go it separately I suspect they might outsource the DSP development and may indeed use an FPGA processor
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Yes, just like Naim, a few other companies build their DACs around TI DA chips and SHARC DSP. The FPGA approach represents something quite innovative and seems to have strong advantages when designing the analogue part. The counterpart is the FPGA code, which is rather complex.
An FPGA based architecture is probably a wise direction. It means a potential long term evolution.
Hopefully Naim will have more than half an eye on the latest and brightest relevant PhD students around the world, if they have not already signed them up.
I am not sure the FPGA changes the architecture neccessarily, but it does give more flexibility in designing bespoke controller software and hardware for DSP and the like for your environment. Of course Rob Watts uses the Xilinx FPGA processors in the Hugo series.
We all like and can hear different things, but for me the dave and tt2 just did detail and little else. No real emotion to the music. I was a bit disappointed with them as i went in with maybe this could be what i need, but it was not to be. But i can see why someone might but its certainly very different to the naim nd555.
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Hi Dunc,
This is in no way a “defend Chord” reply, but when you heard DAVE, was it on its own or with an M Scaler? I would be interested to learn of your impressions of it with the M Scaler.
Setting aside considerations of budget, I too prefer your new streamer to the Chord combo for the way it makes music flow.
Best regards, BF
On it’s own, as the m scaler was out, but to be honest the price once you add up dave, m scaler and a streamer and then some decent cables between the dave and m scaler. The price new was quite shocking really.
Then add in a new dave can’t be far away, what with the tt2 snapping at it heels. I decided that it wasn’t for me.
Plus i felt the dave was quite lean sounding and all detail. That on the same system where an updated ND555 sounded much nicer, but less detail and then the rossini had the detail and the nice sounds the nd555 produced.
I know the m scaler makes a difference and it might have made all the difference, but it wasn’t to be and then this rossini player and clock turned up at a price that made jt easy for me to just say YES and be done with it all
Thanks for the feedback Dunc. We seem to hear the differences between these streamers in a similar way.
Best regards, BF
I did try a power conditioner, but decided in the end that Naim PSUs were not ideal for my cottage. I have dedicated mains from a separate consumer unit for my audio systems as well.
It is frustrating my Naim kit had this problem and I realise some other manufacturers also have buzzing transformers. I’d also stress all the Naim kit worked perfectly well at my dealer’s and has long been sold on and as far as I know is giving excellent services to others, Moreover, a Nait 5i did not have any problems in my cottage.
I commend my dealer and Naim for trying hard to help me solve the problem, but sometimes you just can’t win. That said, I’m delighted with what I have now so all’s well that ends well. The added bonus is I no longer have to leave everything powered up around the clock so it has its compensations.
FPGAs aren’t hard to program. Xilinx Vivado design suite has a System Generator for DSP, which lets a programmer define, test and implement DSP designs. Rob’s expertise is in creating his WTA and Pulse Array DAC designs: that’s the hard bit in my opinion.
FPGA builds are done using IP blocks (prewritten code blocks - IP is intellectual property) making creation of task specific engines painless. If you’re interested and have not programmed FPGAs then check out Intel’s : FPGAs for Dummies.
If you have written some C or C++ code then you should find FPGAs straightforward. Implementation is easier than design.
I think if Naim wanted to go in that direction then they could find staff to do the coding easily enough.
I did. In fact, I did quite a lot.
I didn’t mean that FPGA programming was something difficult. It isn’t.
What isn’t easy is designing a the DAC itself, a good design, as you mentioned yourself.
That isn’t a job that any “out of the box” student could do 
But I’m sure Naim will find its way through the options available. FPGA or not. They certainly have the needed resources (Focal should provide the needed).
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Difficult is a relative term. To create code and for it to sound good and keep interference and side effects to a minimum takes a lot of effort and trial and error. Both Naim and Watts know about that.
In fact Watts told me creating the code for the original Hugo was quite a challenge… specifically getting the code to work in the space available and sound as good as it could.
Watts has also created his own windowing algorithm (WTA) for his FIR reconstruction filter as opposed to using standard ones typically used else where such as a Hamming window or Blackman window. This is a key part of his DSP reconstruction filter code and perhaps part of his drive to increase filter response kernel sizes (taps).
However Watts’ background was VLSI logic chip design and was well placed and experienced to write the FPGA code to keep artefacts, noise and timing issues to a minimum… and was able to take advantage of the new low power FPGA processors from Xilinx could bring… and to use his own algorithms required him to use an FPGA rather than more established building blocks available in a SHARC processor or similar.
Naim use the newer low power AD SHARC processors… but use IIR filters which are typically less prone to creating processing noise at the expense of reduced phase linearity performance… this will be an interesting area to watch to see if Naim jump to FIR filtering in their next generation DACs. Whether it’s FPGA or a SHARC processor is less of an issue to my mind.
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And as usual,.not a word about prioritizing for the best soundquality 
.
I think most people in this hobby primarily prioritize for best soundquality.
With some exception that we see above 
.
Because I know that you have a Linn DSM-product,.but not at what level…
• Majik.
• Akurate.
• Klimax.
But a Linn DS or DSM-product…
ALWAYS Sounds Better If It Is Turned On 24/7.
This was true in 1985 with their Linn LK1 pre-amp,.and it still applies.
/Peder🙂
Anyone remember those great Wadia designs … 13 taps. Another DAC that was well received, the Luxman DA07 had 3 taps.
Those were the days…i think the Wadia dacs are still around, seem to have dropped off the hifi table?
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