[dsperber]

Back in early 2018, after I'd had my revelatory demo of the A16 + headtracker at CanJam SoCal I decided to start using it at my viewing/listening location where it was physically feasible to place the TV-located piece where it needed to be. So I tried to locate one (or both) of the two pairs of devices which came with the two A8's I have.

One of them (the 2009 original) was easily located, but the rechargeable battery (from 2009) had apparently totally died from non-use and age, and could no longer be charged. I inquired of Lorr if it was possible to have the battery replaced in it (by Smyth) and he said "not possible". Since that time I believe I've read that it is physically possible to pry open the HT and change the battery, but this isn't a service offered by Smyth. Nor did they have any "spares" for sale.

Asking if I could buy extra A16 HT's to use with the A8, he replied: "The A16 tracker is not compatible for use with the A8 set-top." This was in April 2018.

As it turns out I eventually found where I'd put the carton containing the second one (from 2013), and thankfully its HT battery could still be re-charged. So that's the one I'm now using, leaving it plugged into the related A8 for topping off when not actually being used atop my headphones.

So as of April 2018, per Lorr it doesn't appear that you can use an A16 HT with an A8 set-top unit.

 

[audiohobbit]

I'm pretty sure you are wrong. In the beginning of 2017 i've got an email from Mike stating that the electrical hardware of the A16 tracker/set-top is compatible with the A8 and they plan to release a firmware which gives the option to select the attached tracker model.
Of course its been a while and no one knows if they still hold on to it.

Well, as anyone should know by now, what thay plan and what they do are totally different things...
(maybe Mike got fired because of that wrong info... just kidding. But I really want to know why Mike isn't mentioned anymore. Hopefully it's nothing with his health. I talked to him at the High End Show and he was such a nice guy!)

They have the FAQ online, and it clearly says:

Q. Is the A8 head tracker compatible with the A16 ?

No. The head tracker has been upgraded to include a 3-axis gyro and 3-axis magnetometer as well as the single axis optical sensor. The new hybrid head tracker can now measure 360 degrees for head azimuth, elevation and roll and it can operate with or without the optical (set-top) reference during playback. However, we still recommend engaging the optical mode during PRIR measurements. The hybrid head tracker design is no longer wireless due to issues with battery longevity and the inconvenience of having to constantly recharge.

> https://smyth-research.com/frequentlyaskedquestions/

 

[Erik Garci]

Asking if I could buy extra A16 HT's to use with the A8, he replied: "The A16 tracker is not compatible for use with the A8 set-top." This was in April 2018.

Even if the A16 head-top cannot be used with the A8 set-top, maybe it can still be used with the A8 but without the set-top, since the A8 has a jack for a wired head-top.

According to the FAQ, the A16 head-top can "can operate with or without the optical (set-top) reference during playback."

 

[Erik Garci]

They have the FAQ online, and it clearly says:

Q. Is the A8 head tracker compatible with the A16 ?

That's not necessarily the same as "Is the A16 head tracker compatible with the A8?"

 

[dsperber]

Even if the A16 head-top cannot be used with the A8 set-top, maybe it can still be used with the A8 but without the set-top, since the A8 has a jack for a wired head-top.

Did you mis-type? Did you mean to say that "the A16 has a jack for a wired head-top"?

The A8's jack is for receiving input from the wired set-top unit, not for receiving input from a wired head-top unit which doesn't exist for the A8. The A8's head-top IR-emitter unit is wireless and battery powered (and thus must be kept charged using the A8's USB charger port), blasting out its IR to the set-top receiver, which sends its thoughts to the A8 for processing via wire going to the A8's input jack.

As I understand it, the A16's head-top unit is now wired (with no battery, so it does not require re-charging... although it does have a long wire dangling off of your head), and because of the new built-in gyros and motion sensors can operate all by itself not requiring the set-top unit at all. I admit I'm confused about how this works, either with or without a set-top unit. The rear of the A16 shows an input for "set-top", so would that instead actually be where the cable from the head-top unit plugs in if you weren't using the set-top unit? Or is there a separate second port for the head-top unit cable to connect?

And if the set-top unit IS used, is it still a receiver, with IR emitted by the head-top piece, same as was true with the A8? And if it were being used, is the new gyro input from the head-top unit just ignored?

I admit I haven't really studied whatever explanatory documentation is currently available on this. I was kind of just waiting to actually receive the A16 before learning about it in detail.

 

[sander99]

A16: On the front for users A and B next to the headphones output connections there are the two connections for the head-top (labeled HT). On the back is the connection for the set-top (labeled Set-Top). (On a side note: It looks like there are three connections to the left of that - the middle one labeled HT Slave - my guess is that you can connect those three to the HT and Set-Top inputs of a second A16 for "cascaded operation" to do 32 channels with 2 A16's.)

 

[dsperber]

A16: On the front for users A and B next to the headphones output connections there are the two connections for the head-top (labeled HT). On the back is the connection for the set-top (labeled Set-Top).

Aha! My old picture of the front of the A16 didn't have the annotations on it, so I didn't see the "HT" inputs. I only saw the "set-top" input on the rear, since my rear A16 picture did show all of the annotations. Thank you for clarifying this.

So I guess if you do use the set-top unit, then it's still an IR receiver sending its signals via wire to the set-top input on the rear of the A16. And that would revert the head-top unit to presumably operating in IR-emitter mode (same as with the A8), with all of the new gyro functions disabled. But the head-top unit still needs to power its IR emitter, and thus the cable going to the front HT port on the A16 (since it no longer has a rechargeable battery).

Otherwise, with just the head-top unit being used, now the gyro functions do it all, both obtaining power as well as communicating real data through the same cable going to the front HT port on the A16.

 

[sander99]

with all of the new gyro functions disabled.

No I don't think so. The head-top is always doing most of the work. The set-top is only used to automatically re-calibrate the head-top (at small regular intervals I think). If you don't use the set-top the head-top could slowly drift away a bit over time (but maybe can be manually reset by pushing some button while looking straight forward).

Edit: from additional_KS_info.pdf:

A16 Head Tracking
Like the A8 the Realiser A16 uses an accurate 200Hz low latency head tracking unit to de‐rotate the
virtual loudspeakers in the presence of listener head movement. However the A16 head tracker is
significantly improved over the previous generation. First its core is built around a 3‐axis gyroscope
and 3‐axis accelerometer (known as an Inertial Measurement Unit or IMU) giving it the ability to
simultaneously track heading, pitch and roll. Second it incorporates a 3‐axis magnetic stabilisation
circuit as well as the single axis optical measurement feature of the first generation system. This
gives the listener three ways in which to use the new head tracker.
1) IMU only operation. In this mode the head tracker operates entirely on its own. The listener
first resets the head tracker direction reference while looking centre. The IMU is stabilised
using only the accelerometer meaning that the tracker heading can slowly drift over time.
However we incorporate an exponential leakage algorithm that can largely mitigate this
effect for normal listening situations. This mode of operation is recommended for casual
listening situations or for live applications where slight drift is acceptable.
2) IMU combined with magnetic stabilisation. In this mode the head tracker operates entirely
on its own and a magnetic heading is used to recalibrate the IMU heading thereby cancelling
any tracker drift. Since the earth’s magnetic field around the tracker depends on the type of
headphone and the electromagnetic environment that surrounds the listener, the
magnetometer must be calibrated using a very simple procedure with the head tracker
mounted on the headphone and in the listening environment. This mode of operation is
recommended for more critical listening situations.
3) IMU combined with optical stabilisation. In this mode the listener must use the supplied SVS
set‐top to provide the optical looking‐centre reference, usually located on the TV set or
monitor. As with the magnetic stabilisation, the idea is for the optical reference to
recalibrate the IMU thereby cancelling drift. Although this mode seems similar to the first
generation head tracker the new head tracker will continue to function even when the
optical path is interrupted. The superb tracking accuracy and repeatability of the optical
stabilised mode is particularly useful when undertaking PRIR measurements but can also be
used for general listening.
In the IMU only (1) and IMU with magnetic stabilisation (2) modes the user has the option to
connect the supplied SVS set‐top unit to display the heading and pitch output from the tracker.

 

[jgazal]

It would be so nice to have the A16 manual available.

 

[Erik Garci]

Did you mis-type? Did you mean to say that "the A16 has a jack for a wired head-top"?

No, I didn't mistype. The A8 has a jack labeled "HT" on its front panel, similar to the two jacks on the A16's front panel. The A8's manual states that this jack is "for wired head tracker (not provided)."

The A8's wired set-top connects to the "IR REF" jack on the A8's rear panel, by the way.

 

[dsperber]

No, I didn't mistype. The A8 has a jack labeled "HT" on its front panel, similar to the two jacks on the A16's front panel. The A8's manual states that this jack is "for wired head tracker (not provided)."

The A8's wired set-top connects to the "IR REF" jack on the A8's rear panel, by the way.

AHA (again... another moment)! I stand corrected (also... again). You're absolutely right. Mea culpa.

Probably because for almost a decade with the A8 I had never used the head-tracker my understanding and familiarity is clearly woefully lacking. I hadn't remembered about the HT jack being physiucally present on the front of the A8, since it really is 100% unused with the released product. It's apparently only present on the A8 for possible future use given the actual non-wired battery operated version of the head-top unit for the A8. The engineering design has now, finally, been "realized" with the A16 which now does make use of it for its own wired head-top unit.

 

[phoenixdogfan]

Does anyone know the status of the Illusonic Mixer? Will it be operational when the A16 ships (if it ships)? Also since the A16 provides analog outputs and can double as a multi channel processor control center will it also include such control center features as bass management for speaker setups?

Would be interesting to know the extent the Realiser can be used as something other than just a binaural headphone virtualizer.

For instance, anything that would allow it to do DSP or function as an equalizer/electronic crossover?

I know none of this has come up in previous discussions, but I wonder if there might be some hidden capabilities that a clever user could bring out on this potentially powerful unit which would help to justify its hefty price tag.

 

[Eich1eeF]

Would be interesting to know the extent the Realiser can be used as something other than just a binaural headphone virtualizer.

It should function as an AV processor. I'm kind of hoping that one day, the Smyths would implement Dirac live, because that's already available for the MDS DSP board used in the A16.

For instance, anything that would allow it to do DSP or function as an equalizer/electronic crossover?

Parametric EQ would be a good start to use for room correction when used as a AV processor.

I know none of this has come up in previous discussions, but I wonder if there might be some hidden capabilities that a clever user could bring out on this potentially powerful unit which would help to justify its hefty price tag.

If it could function as a full fledged AV processor, it might be cheap in comparison to other products, especially if a digital 16 channel output board were made available. Comparable devices like the Storm Audio ISP or Focal, or the Trinnov cost at least 4 times as much as the Realiser.

 

[phoenixdogfan]

It should function as an AV processor. I'm kind of hoping that one day, the Smyths would implement Dirac live, because that's already available for the MDS DSP board used in the A16.

Parametric EQ would be a good start to use for room correction when used as a AV processor.If it could function as a full fledged AV processor, it might be cheap in comparison to other products, especially if a digital 16 channel output board were made available. Comparable devices like the Storm Audio ISP or Focal, or the Trinnov cost at least 4 times as much as the Realiser.

It would also be nice to know the performance stats of the subunits in the A16. Based on the flow diagram, it looks like the unit has a 16 channel Dac, two 2 channel Dacs, a 16 channel AD unit, a low power 10w or so amp. Hopefully, once this thing is released someone will send one to Amir at ASR and he can put it on his Audio Precision unit to determine what the performance stats (SINAD, THD, IMD, power on amps) are for each of the subunits. If for example the headphone unit put out 2 watts at 32 ohms and had a 110 Sinad or better, no one would probably ever need a DAC or headphone amp ever again. If on the other hand the SINAD is around 90 db (like some Schiit currently on the market), I'm sure a lot of us would refrain from putting our THX 789 or OCTO 8's on the market anytime soon.

 

[Zenvota]

It would also be nice to know the performance stats of the subunits in the A16. Based on the flow diagram, it looks like the unit has a 16 channel Dac, two 2 channel Dacs, a 16 channel AD unit, a low power 10w or so amp. Hopefully, once this thing is released someone will send one to Amir at ASR and he can put it on his Audio Precision unit to determine what the performance stats (SINAD, THD, IMD, power on amps) are for each of the subunits. If for example the headphone unit put out 2 watts at 32 ohms and had a 110 Sinad or better, no one would probably ever need a DAC or headphone amp ever again. If on the other hand the SINAD is around 90 db (like some Schiit currently on the market), I'm sure a lot of us would refrain from putting our THX 789 or OCTO 8's on the market anytime soon.

heh... 16 channels of data(15-20mb/s for uncompressed object tracks) into 2 channels, doubled for the binaural rendering + room reflections, in a limited 32/48 container(whats that 3mb/s per channel?) and the concern is snr and thd in a feedback opamp?
ε-(´・｀) ﾌ