Tact - New Ambiophonic room correction processor

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I have always been interested in "supplementing" my two channel set up with some type of surround devise, other than the typical 5.1 channel processor. Once having heard back in the 80's a processor by ADS that simply added depth and ambient sound to a 2 channel system by adding two rear speakers and digital matrix processing.

There is a new possibility recently released by tact, called the Tact-Ambiophonics processor. The description on their web site is as follows:

"Tact-Ambiophonics is the latest addition to our family of room correction processors. This four channel processor is capable of simultaneously processing four digital or analog input channels. It provides four digital or analog outputs that can be configured as full range or subwoofer outputs. One of the unique features of this product is Ambiophonics cross-talk cancellation on four channels."

ALSO . . . .

"Now a revolutionary way to playback your existing library of LPs/CDs/DVDs/SACDs/BDs

Tact-Ambiophonics is the latest addition to our family of room correction processors. This four channel processor is capable of simultaneously processing four digital or analog input channels. It provides four digital or analog outputs that can be configured as full range or subwoofer outputs. One of the unique features of this product is Ambiophonics cross-talk cancellation on four channels.

Recover the spaciousness and depth that old-fashioned stereophonic and surround loudspeaker arrangements and processors leave on the disc.

Tact Ambiophonics is so named because it is destined to succeed the 80-year old stereophonic and similar surround loudspeaker arrangements in the domestic sound reproduction of music, video or games.

This new generation Tact-Ambiophonics digital processor includes real-time processing logic (RACE/XTC) that allows for the recovery of all the localization cues consistently and fortunately inherent in most standard CDs, LPs, and surround media but discarded and never utilized in conventional two-speaker stereo systems. The result is a flat stage whose width is restricted to the angle between the speakers, and a sense that the sound is canned. Ambiophonics also eliminates other inherent stereo psychoacoustic distortions related to head shadow and pinna functions that make localization vague, non-linear, and cramp the sweet spot."

Price: $2490.00

Here is the link:
http://www.tactlab.com/Products/Ambiophonics/ambiophonics.html

Is this meant to be used as a stand alone unit or with a pre amp?
It "sounds" like it processes BOTH front and back 2 channels.

Does this mean I can play a DVD with 5.1 surround, or a SACD in my OPPO unit even though it's only hooked up to a 2 channel cary SLP-03 pre-amp, and this unit will be able to process ALL of the 5.1 info into the tact unit and 4 speakers?

Can someone shed some light on just how this unit interfaces with an existing 2 channel system?

Not good with inputs/outputs, just the simple set up . . . . :eek:

THANKS!

Joe M.
 
Hi Joe, I heard this system at last January's CES show and spoke to Boz a bit about it.
It's not unlike a lot of other phase-managed 'ambiance' recovery solutions that play with interchannel cross-mixing of certain portions of the signal on 2 ch systems.

So it is definitely designed for 2ch setups (and one small sweet spot).

The fact that it has 4ch output is more to allow great speaker to sub integration. TacT does that very, very well.

And since it also incorporates the Room Correction features as well, it has very good in-room performance.
I was interested in this unit mostly as a nice one-box solution to having a preamp, crossover and room corrector for a secondary 2.1 setup I have.

If that's all you are after, then its worth looking into.

However, it is not a 'surround' processor. they talk about BR/SACD/DVD-A, but it is 2ch inputs only.

If you have multichannel audio (and movies), then you need a different box than this.

Also, Ambiophonics was largely developed on monopole, point source speakers. They did not have a good answer as to how a large dipole would impinge on the effect. My guess is it totally screws it up, as the timing of the rear reflections is random from a design point of view (everyone's rooms and placement being different). So I'd not expect that to be a plus with ML's.

Bottom line: no this is not what you are looking for (I think).
 
I've read at another site that the Lyngdorf RC1 or RP1 worked wonders on some big Finial ESLs (sic) in a 2 channel home set up.

I've also read that the new McIntosh MEN220 which is licensed from Lyngdorf was very helpful on the CLX. The fellow mentioned he was able to have the CLX 2 foot off the front wall and still preserve the sound we're accustomed to.

Gordon
 
Nice summary by Jonathan. This looks like a less-expensive version of TacT's 2.2XP, which also includes XTC (ambiophonic) processing. I've played with the XTC feature very briefly - not enough to form any opinion. By all accounts, it's tricky to setup properly, and is only effective for a tiny sweet spot i.e. don't move your head an inch to the left or right. A brief description of the process may be found here.

TacT does make a well-regarded HTP, but it ain't cheap @ $15K.
 
I've read at another site that the Lyngdorf RC1 or RP1 worked wonders on some big Finial ESLs (sic) in a 2 channel home set up.

I've also read that the new McIntosh MEN220 which is licensed from Lyngdorf was very helpful on the CLX. The fellow mentioned he was able to have the CLX 2 foot off the front wall and still preserve the sound we're accustomed to.

Gordon

Hi Gordon, the benefits noted there are from the room correction. A feature I'm pretty hot on. Although IMHO, Audyssey does a better job than TacT (for both scientific and measured reasons I've identified elsewhere).

The 'new' Ambiophonics feature is unique to this new box as far as I know.
 
Nice summary by Jonathan. This looks like a less-expensive version of TacT's 2.2XP, which also includes XTC (ambiophonic) processing. I've played with the XTC feature very briefly - not enough to form any opinion. By all accounts, it's tricky to setup properly, and is only effective for a tiny sweet spot i.e. don't move your head an inch to the left or right. A brief description of the process may be found here.

TacT does make a well-regarded HTP, but it ain't cheap @ $15K.


Agreed the XTC process is a variant of an HRTF (head related transfer function) for speakers (vs headphones). Positioning is critical to a very high degree.


Oh, and while they have an HTP, for half that amount, the Denon AVP beats it IMHO, and it has a better Room corrector.
 
Oh, and while they have an HTP, for half that amount, the Denon AVP beats it IMHO, and it has a better Room corrector.
Heh, an ongoing debate @ AVS, involving some large egos.;) I had thought that Audyssey Pro won't handle LFE (without the separate Audyssey bass-correction box) and isn't tweakable more than +-3dB. Have I got that wrong?
 
So it is definitely designed for 2ch setups (and one small sweet spot).

The fact that it has 4ch output is more to allow great speaker to sub integration. TacT does that very, very well.

. . . .

However, it is not a 'surround' processor. they talk about BR/SACD/DVD-A, but it is 2ch inputs only.

If you have multichannel audio (and movies), then you need a different box than this.

From the description given above, this unit can handle 2 OR 4 speakers.
When I refer to "surround" I may have used the wrong word! I do not want the traditional discrete channel "surround", but I am looking more for the "matrixed" sound where the air/ambience is added in, but you can't tell it's coming from a discrete speaker. I still recall the 1980's ADS unit that did this.

So it "sounds" to me that this unit can do 5.1 channel processing with 4 speakers, that is a form of surround. Check out the link in the first posting to go to the Tact site for full description.

Again, I don't have a good grasp of all the input/output types, so . . .

I'll guess the analog inputs are for the CD/SACD player (OPPO), turntable and TV. Digital input can be the Squeezebox or a DAC.

There are TWO sets of analog imputs. Is this one for the front pair of speakers, and the other for the set of rear speakers?

What are the Digital outs for?

Where do the sub(s) connect?

Lastly, does this unit have a "bypass" for "regular" non-processed 2 channel, or is the minimum set up their 2 channel processed sound?

I guess I would be replacing my cary SLP-03 tube preamp with this unit, not supplementing it like an add on processor. I'm not sure I'm ready for that, especially since there is no where near me to hear this unti before hand!

:eek::eek:

Joe M.
 
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Apologies for not reading the entire product description. This does, indeed, appear to provide XTC processing for both a front and rear pair of speakers. It's unclear how it processes to provide a "surround" effect, but it appears to do so using a two-channel input and then executing some form of internal processing to create a signal for the rear two channels. Best way to find out is to call the TacT info number and ask questions. Boz answers any and all calls himself, and is a pleasure to talk to.

Analog inputs won't be for speakers, but for source components e.g. CD player, etc.

Digital outputs are for an external DAC or for pure-digital amplifiers, of which TacT makes several. In my TacT system, I've found that using a CD/SACD transport into the TacT and then digital out to an external, high-quality DAC sounds better than using a conventional CD/SACD player. The latter requires multiple A/D steps, which doesn't have a happy effect on SQ, IMHO.

If you use four mains, there's no provision for sub-woofers i.e. you can use two mains and two subs or four mains and no subs.

I don't know if this can be bypassed for conventional 2ch sound, but I do believe that the ambiophonics boys recommend that the speakers be 20-30 deg apart, which is fairly narrow.

I would strongly recommend that you hear this bit of gear before you buy. User reports on ambiophoncs are mostly negative. TacT is far better known for the power and flexibility of their room correction. Even though it's included in many (all?) TacT gear, I don't know a single person who uses the XTC/ambiophonics feature.
 
Heh, an ongoing debate @ AVS, involving some large egos.;) I had thought that Audyssey Pro won't handle LFE (without the separate Audyssey bass-correction box) and isn't tweakable more than +-3dB. Have I got that wrong?

MultEQ XT Pro equipped gear certainly handles LFE, and they even dedicate a larger number of EQ elements (FIR Taps ) to handling the more demanding bass frequencies.

Tweaking the EQ curve in the Pro software might have a limit, but I have not checked where it might be, as my custom curve has a very shallow upper-bass boost (+1db).

Each of the 12 channels in my preamp can have its target curve individually tweaked.

In any case, tweaking that curve beyond 3dB would be pretty 'aggressive' non-conforming EQ. Was someone setting up a Disco? :devil:
 
MultEQ XT Pro equipped gear certainly handles LFE, and they even dedicate a larger number of EQ elements (FIR Taps ) to handling the more demanding bass frequencies.
Reason I asked is that there are many users who add the Audyssey SubEQ box (or SVS equivalent) because it doubles the number of filters available via XT for bass correction, as well as permitting correction of the summed response of two subs. Perhaps the Pro version moots this advantage - the online info is fuzzy, at best.

Tweaking the EQ curve in the Pro software might have a limit, but I have not checked where it might be, as my custom curve has a very shallow upper-bass boost (+1db).
IIRC, I believe Kal's cited 3dB as the limit. Again, may not be true of the Pro installation.

Each of the 12 channels in my preamp can have its target curve individually tweaked.
Same as the TacT. Dunno about others.

In any case, tweaking that curve beyond 3dB would be pretty 'aggressive' non-conforming EQ. Was someone setting up a Disco? :devil:
You're right, and in most cases 3dB is probably more than enough. Still, the flexibility is nice to have.

Have you read Sean Olive's recent blog on Harman's research into "preferred" EQ curves? Fairly interesting once you sort through the agendas.
 
Reason I asked is that there are many users who add the Audyssey SubEQ box (or SVS equivalent) because it doubles the number of filters available via XT for bass correction, as well as permitting correction of the summed response of two subs. Perhaps the Pro version moots this advantage - the online info is fuzzy, at best.

Yes, for folks that want the ultimate in bass correction due to sub/room issues, find that layering on the external unit helps.
One thing I've not managed to get out of Chris (the CTO) is how many taps a given product has for each channel. Just vague relative terms about product A vs B.

The Pro version does not increase the tap count, but does improve the algorithms applied to calculating the corrective impulse response.

In the case of my preamp (the Denon AVP), I believe it has a similar capability (in terms of taps) as the stand-alone product.
The AVP can apply Audyssey even at high bit rates (24/96 PCM w/12 channels), as well as individually measure and correct up to three subwoofers. That requires pretty massive DSP and memory.


IIRC, I believe Kal's cited 3dB as the limit. Again, may not be true of the Pro installation.
Kal should know, he has a pro set up, as do I.
I'll check this next time I run it.


Have you read Sean Olive's recent blog on Harman's research into "preferred" EQ curves? Fairly interesting once you sort through the agendas.

Thanks, that was a great article.

Glad to see them doing that level of research on the topic. And I'm really phsyched about the development of their new room corrector.
One thing they did NOT address was the fact that some of the room correctors address temporal domain as well. I would have loved to see waterfall plots of the various results.
 
Digital outputs are for an external DAC or for pure-digital amplifiers, of which TacT makes several. . . . .

If you use four mains, there's no provision for sub-woofers i.e. you can use two mains and two subs or four mains and no subs.

THANKS for all of the insights . . . . !

Since I believe the amplifiers in the powered subs from ML (Deph i and Descent i) are class D, and those are considered digital, could those subs be plugged into the ditital outs?


You would think Tact would have put three analog out pairs on this baby: one for the front, one for the back, and one for the subs.
 
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THANKS for all of the insights . . . . !

Since I believe the amplifiers in the powered subs from ML (Deph i and Descent i) are class D, and those are considered digital, could those subs be plugged into the ditital outs?


You would think Tact would have put three analog out pairs on this baby: one for the front, one for the back, and one for the subs.
Class D does not mean digital, and even the true 'Digital' amps do not have a digital input per-say. You still need a DAC to convert the digital signal to an analog signal.
 
Since I believe the amplifiers in the powered subs from ML (Deph i and Descent i) are class D, and those are considered digital, could those subs be plugged into the ditital outs?
No, the ML subs cannot be used in this fashion, as they utilize analog and not digital input. Don't confuse Class D with direct digital input. The only amps I'm aware of which accept digital input are TacT, Behold and the new NAD M2, though there may be others I'm unaware of.
 
Class D does not mean digital, and even the true 'Digital' amps do not have a digital input per-say. You still need a DAC to convert the digital signal to an analog signal.
Crossing posts;). See my post above - there are a small number of amps which do, indeed, accept digital input directly.
 
...

You're right, and in most cases 3dB is probably more than enough. Still, the flexibility is nice to have.

Have you read Sean Olive's recent blog on Harman's research into "preferred" EQ curves? Fairly interesting once you sort through the agendas.

I can confirm the 3db limit, as I opened up the Audyssey Pro software today and tweaked my target curve to simulate the 'preferred' curves from the study.

Here's a screen shot of editing the 'target curve' in the Audyssey software.
The points below 100hz are at the +3dB limit.

The target HF curve is what Audyssey calls 'target #2', which interestingly enough just about models the in-room measured performance of my Monoliths above 5Khz, so very little EQ there.

The ESL's benefit from the 2Khz dip in the 'standard' Audyssey curve, and works really well on movies, and any record mastered using B&W speakers ;)

Here's the curve I set up and loaded just now.
A bit 'heavy' for my taste., I think a gentler slope in the bass would work better.

But just like Cola taste-tests, where the sweeter drink wins, I guess most people like mondo-bass.
 

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BTW- the 'preferred' curves in the study had slopes of +5dB below 1Khz. Can't imagine how bass-heavy that is.

With the Infinite Baffle sub, massive room treatments and the Audyssey Pro, I just can't stand boomy, overblown bass anymore.

I can generate low-frequencies that register on the Richter scale in my neighborhood, but it's damn clean. :cool:
 
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