Archive for Hifi Posts

Why an integrated amp? And what have we been up to for the past 24 months?

Integrated amps “don’t get no respect” — or they don’t get the respect they deserve.  There are many reasons for this, beginning with the fact that HiFi is, for many, a hobby unto itself along with a way to enjoy beautiful music. The journey is part of the enjoyment, and separate components allow for experimentation, “tuning” and custom rigs.

But individual components have quite a few drawbacks as well.  Separate pre-amps and amps, first of all, are far more costly for exactly the same circuitry and performance.  Its little known that the chassis is usually the single costliest part of any component.  Add lots of extra jacks, power cords, etc. and this extra costs continues to rise.  Now, let’s move on to those various wires.  Assuming that wires can only make things worse, and the best wires simply are truly transparent, an integrated amp brings two great benefits:  1) there are no interconnects, and b) you save, potentially, $100s or even $1000s by not buying them. I will stay out of the subjective mine field that is costly interconnects.

Finally, for use in real living environments, as opposed to dedicated music rooms/HiFi museums, an integrated amp is smaller, simpler, and likely much more acceptable to a non-audiophile spouse — and to this end we will concentrate on a package that is sized and styled to complement – or at least fit in well – with a traditional design aesthetic.  For the record, in my living room I’m on the side of said, theoretical wives.  A smaller, simpler component probably fits in much better, so long as it sounds absolutely spectacular.  And it can.

There are many more advantages, along with the one big disadvantage:  you cant mix and match exactly what you need, like monoblocks, or a higher powered amp to drive inefficient speakers in a large room.  You must make do with the single size, or maybe two power levels that a manufacturer, like Sonogy, produces.  Yet this is less of an issue than imagined. Consider that power goes up exponentially with volume level and you realize that a doubling of volume requires not twice the power, but ten times the power; say 40W to 400W all other things held equal. Yep its true; so that 40W amp if well designed might do more than you imagine.  Sadly, few are really all that well designed.

Sonogy are out to change all that, and initial feedback from reviewers., bloggers, dealers, and audiophiles is very, very good. And we are subjecting modestly priced equipment to demanding environments, like $35,000 speaker systems: sink or swim little product.

Ugly yet beautiful!  Interior of prototype preamp, used to prove-in most of the integrated amp technologies in a simple form-factor to work on. Click to expand.

Another beauty of doing an integrated amp is that it had made us reconsider, from first principles in many cases, nearly every component in the HiFi chain.  . . . Or most of them anyway since we am still in the early stages of tackling the DAC. DACs however, are not YET always part of an integrated amp, although it is becoming a great feature (again, if done well).  Along our journey Sonogy have therefore either designed from scratch or optimized all of the following:

  1. Preamp stage
  2. Power amp stage
  3. RIAA / Phono amplifier (MC and MM, switchable)
  4. Headphone Amplifier
  5. Logic and control (yes Virginia, there will be remote control….)
  6. Optimization of all the associated power supplies, which, i would argue, matter more than the circuitry itself.  Just to make a point, in this integrated amp, there will be FOUR power supplies.

We plan to cover each of these in its own blog entry.   The interesting implication is that Sonogy has completed new next-generation designs not only for an integrated amp, but for an entire series of components that can be built, in the words of Mercedes-Benz,  “to a standard not to a price”  – and yet for the performance we will deliver we expect that price to be extraordinarily attractive.

Watch this blog for more, as we have the opportunity and time to complete an overview of each development effort, possibly with pictures of pre- prototypes and design notes that the the tech geeks among us might appreciate 🙂

Grant

 

 

Sonogy – Next Generation R&D

Ahh, the trade off, i can spend time actually DOING R&D or communicating it here. But I must remember that sharing that information is part of what this hobby, and a successful business is about. SO i will endeavor to post interesting information on research we perform, and develop as it happens.  The good news is ” I am way behind” – meaning that much has progressed over the past two+ years.  The bad news is, well, I am well behind sharing it here. 🙂  read below to hear what Sonogy is doing on everything from basic product R&D, to testing new an unique ways of achieving superb sound, at a reasonable price, with features and convenience not normally associated with the hgih end.  These are all things I want, and trust they appeal to many of you.

I’ll try to keep blogs to a readable length, and make this post “Sticky” as an introduction.

Enjoy!

 

“Bitperfect” – huh?

After a rather long hiatus from audio technology, i was re-immersing myself in the technology — especially with regard to the evolution of digital formats and streaming.  An odd word kept coming up – “bitperfect” – commonly used, almost never defined, what the heck? Of course bits are perfect. The problems are all analog.

I’ll not go down this rat-hole today, but suffice it to say that digital audio signals have analog characteristics to them that have direct impact on the reconstruction of the analog wave.  More on THAT later.

So what is “biperfect” and what’s imperfect about much digital (computer) audio?

I’ll oversimplify.  Most of this has to do with how volume is controlled in computer audio.  One would think that once in the digital domain, manipulation – for example turning down the volume – would be easy and without distortion.  In theory, it can, but in reality, one would be wrong. the vast majority of music is coded initially as “RedBook” – CD format with a resolution of 16 bits – or “65,000 shades of gray” which is pretty darned good – and IMNSHO, NOT where the problems in CD audio lie.  But if we simply do volume-control multiplication (like make it half as big) on the 16-but words, we slowly lose resolution (think through the math its true). If this doesn’t make sense – think about an extreme example – we digitally “turn down” the volume  99.99something% of the way and are left with only three digital levels – zero, one and two.  This is two-bit resolution and will sound like absolute crap. That’s a technical term.  For a comparison, if you can, turn your monitor to 4 or 8 bits of color and look at the screen.  Yuk.  ‘nuf said I hope.

You can see the numbers in a presentation by ESS Technology here:

http://esstech.com/files/3014/4095/4308/digital-vs-analog-volume-control.pdf

To get it right we need to do two things:

  1. do our math at higher resolution, for example 24 or 32 bits, so we can maintain full 16 bit resolution,
  2. **AND** directly convert these higher-resolution words to analog (meaning a 32-buit conversion process) so we don’t truncate that resolution.

Simply doing the math in 32 bits is pretty simple. Yes, we’d need some code to convert it and do floating point math, and we’d need to temporarily save the much bigger buffered file, but that’s easy for machines that edit in photoshop.  The problem comes next; we need to convert this 32 bit word into a squiggly AC analog music voltage.  Problem: we have a 16-bit D/A chip.  And all the interfaces (SPDIF, AES/EBU, carrier pigeons).

You can read more about it, but the bottom line is this: in 99% of all cases, and 100% of all PC/MAC/LINUX cases, you should never use the digital volume control – that convenient little slider.  Just say no.  Set the volume to full and send the output to your DAC or networked digital player – and let ALL the bits get there, to be converted to a nice, clean, high-res music signal.  Then you can attenuate it with good, old-fashioned resistors.

(note: if you are just playing MP3 files through the sound card to your earbuds, none of this really matters)

So “bitperfect” is a word that we should never have had to invent nor explain. It comes of shortcuts made in commercial music players.

Fortunately, most high res players with real aspirations know this, and take care of it. JRiver, Roon, etc. are all bitperfect. Sorry to leave out many others.

I’ll add that for Macs there is a surprisingly good app that simply takes your iTunes library and hijacks the signal, delivering it without manipulation – in other words, “biperfect” and costs $10.  Its called….. Bitperfect for Mac.

Enjoy!

 

Grant

CEO, Sonogy Research, LLC