Nice job Alexc. Please keep us up to date.
Review: Tact Audio Tact-2.2 Preamplifier
Category: Preamps
I have lived with the Tact 2.2X in my system for nearly three months. It replaced a BAT VK5i SE, which was (and still is) the best line stage I have had in my system. I had absolutely no complaints about the BAT nor a desire to "upgrade" while I lived in the US and had my system set up in my small, but properly designed and built, dedicated listening room (concrete slab floor, no windows, length and width chosen to minimize standing waves, etc). However, I had to give this room up when I was transferred by my employer to Venezuela. I was able to find an apartment large enough to have a dedicated listening room, but the new room is an acoustical nightmare, with flimsy sliding glass windows on exactly half of the wall behind the speakers, springy hardwood floors,a plaster ceiling suspended from I-beams, a large and deep staircase well leading into the room thru a sliding hard wood door, etc, etc. No matter how many CARA and RPG simulations I ran, the results was always muddy and boomy bass, and the BAT's midrange magic was utterly lost in the process. Listening to my system was no longer enjoyable....
So...after much deliberation, I ordered a TACT 2.2X from the local dealer (sheer luck- the ONLY hi fi store in Caracas carries Tact, and the owner's main business is industrial/commercial acoustical design and consulting).
My listening preferences run the gamut from jazz to classical to blues to pop to rock. I listen to vinyl about 60% of the time. For my Tact evaluation and set up, I relied heavily on the Chessky Demonstration disc, Holly Cole's Temptation, Jennifer Warnes' Famous Blue Raincoat, Neri Per Caso's So This is Chritmas, Jazz At the Pawnshop, Cantate Domino,and Belafonte At Carnegie Hall (all on CD).
I listen at fairly high levels (85 to 90 dB), and look for the usual qualities in a high end system, with a bias towards midrange warmth and "precise" soundstaging.
Before implementing any digital corrections, I assessed the TAC only as a DAC (with the BAT still in the system) and as a DAC/preamp. I found the TACT's 24/192 upsampling DAC to surpass the Muse's non upsampling 24/96 DAC in the areas of detail/resolution, soundstaging, and bottom end extension. Out of the box, the TACT was noticebaly brighter than the Muse, lendig a somewhat artificial character to the music, but this improved after a week of burn-in, and even more after connecting a Top Gun HCFI, Bybee Purifier, and Marigo 5.0 digital cable. Though the Muse on its own was warmer and more natural, I could live happily with either presentation.
Taking the BAT out of the system revealed the TACt to be an outstanding preamp on its own. Yes, the BAT's midrange warmth was gone, but the difference was surprisingly minor to my ears. In terms of high end extension, soundstage width/depth,and imaging the TACT was definitely in the same league. Note that at this time my amps were Aronov 9100's - the CJ's came later...
Having established the basic merits and shortcomings, I moved on to the measurement and correction stage. Measurements using the Tact's calibrated microphone confirmed that the frequency response in my room was a nightmare below 80 Hz, with peaks as high as 10 dB and holes as deep as 12 dB. Also, due to room interactions, the right channel output level was ~ 3dB higher throughout a good portion of the frequency spectrum.
My first attempts at using the TACT to correct the response were disastrous. The TACT's user manual is good only as fire kindling. It is absolutely essential to join Tact's Yahoo User's Group and pretty much read all the messages posted so far, and even better to work with someone who has climbed the learning curve already. While the Tact is capable of computing and applying correction filters to make the response curve perfeclty flat...your system may not be up for it. After trial and error, posting questions on the User Group, and 3 visits from my dealer, these are some of the generalizations I've come up with so far:
1. The TACT allows you to completely change the frequency response curve of your speakers, to enhance the midrange, to boost the bass, etc. My counsel is -- DON'T. If you force your speakers to sound/act in ways they were not designed for, they will not be happy. I did implement a mild roll-off of the very top end to tame the TACT's inherent brightness, but after playing around with various midrange and bottom end boosts I settled for a target frequency response which basically reproduced the Guarneri's natural, very linear response.
2. If you try to fill in big "holes" below 200 Hz or so, you WILL overstress the drivers in your speakers. In the end, I left the "holes" below 200 Hz untouched unless the X-over frequency placed them squarely in the subwoofer's domain. The mid/bass drivers on the Guarneri's are simply too small to deal with anything more than a 1 dB correction at these frequencies. A hole at these frequencies is barely noticeable, and far less objectionable than a either a peak or the sound of your mid/bass driver reaching its maximum extension and trying to go further!
3. Conventional subwoofers are too slow. Based on the response of my Guarneri's, the ideal X-Over frequency would have been 100 Hz, but the RELs cannot deal with this. A x-over point above 60 Hz will muddy up the bass, since the REL's cannot move fast enough to sound musical when asked to reproduce 100% of the signal in this range. This is simply not what they were designed to do.
With the X-over set between 50 and 60 Hz, the peaks removed, the holes left alone, the left and right channel levels matched by the TACT, and the sub/main response time-aligned by the Tact the result was......a revelation.
The soundstage is huge, wider than I've ever heard it. Placement of instruments and soloist withing the soundstage is tack-sharp and very well delineated. The bass is flat and tight down to 16 Hz (yes,the Stratas DO go that low in my room). The midrange is detailed and articulated as never before, now that the mid/bass drivers do not need to reproduce anything below 50Hz. The top end is super clean, very musical and detailed. Brass (e.g., in Arturo Sandoval's "Hothouse") has the proper bite and blat but is never shrill. Low level resolution has also taken a huge step up now that the sound is freed from bass colorations.
Oh...as for the midrange magic lost with the BAT...replacing the Aronov amps with the Premier 8XS has taken care of that in spades. Using Svetlana EL 34's in triode mode, the 8XS bring a palpability, presence, and warmth to the mids that is to die for..and which probably would have been too much of a good thing combined with the BAT. Althought the 8XS "only" deliver 130 watts or so a piece, they are working well within their comfort zone since they too don't need to worry about anything below 50 Hz.
Last....what does vinyl sound like thru the Tact? Pretty damned good. The A/D module on the 2.2X samples the analog signal at 24/192 and that seems to be more than enough. Yes, perhaps some ineffable "air" is lost in the process, but the improvements wrought by the correction in other areas far offset this. To be fair, the Pass XONO (which recently replaced a Linn Linto in my system) helps a lot. The XONO plus TACT combo certaily beats my Linto sans TACT, so overall I'm a step ahead.
So (as my wife asked) am I "done"??? Of curse not! I really would like to try faster subwoofers so that I can raise the X-over point to 100 Hz and "fill in" the nastiest holes in the frequency response without blowing a driver in the Guarneri's. TACT makes their own subs for this purpose, and they are certainly on my "next" list.....
Associated gear
Linn LP12 (Arkiv B, Ekos, Lingo)
Muse Model 9 Signature CD Player
Pass XONO Phono Preamp
Conrad Johnson Premier 8XS Amplifiers
Sylvania Gold Brand 5751 Tubes
Brimar/Mazda 6FQ7 Tubes
Sonus Faber Guarneri Homage speakers
2 REL Strata III Subwoofers
Audioquest Diamonond X3 Interconnects
Audioquest Dragon SE speaker cables
CPC Top Gun Power Cords
CPC Top Gun HCFI Power Cords
Marigo Reference 3.03 Signature Power Conditioner
Bybee Quantum Power Chargers
Bybee Interconnect Filters
Bybee Ultra Speaker Purifiers
PS Audio Ultimate Outlets
Mana Level 4 Compnent Rack
RPG Studio in a Box Room Treatment
2 Siamese Cats (randomly placed)
Similar products
BAT VK5i SE Preamp
Linn Kairn Pro Preamp
Linn Wakonda Preamp
I have lived with the Tact 2.2X in my system for nearly three months. It replaced a BAT VK5i SE, which was (and still is) the best line stage I have had in my system. I had absolutely no complaints about the BAT nor a desire to "upgrade" while I lived in the US and had my system set up in my small, but properly designed and built, dedicated listening room (concrete slab floor, no windows, length and width chosen to minimize standing waves, etc). However, I had to give this room up when I was transferred by my employer to Venezuela. I was able to find an apartment large enough to have a dedicated listening room, but the new room is an acoustical nightmare, with flimsy sliding glass windows on exactly half of the wall behind the speakers, springy hardwood floors,a plaster ceiling suspended from I-beams, a large and deep staircase well leading into the room thru a sliding hard wood door, etc, etc. No matter how many CARA and RPG simulations I ran, the results was always muddy and boomy bass, and the BAT's midrange magic was utterly lost in the process. Listening to my system was no longer enjoyable....
So...after much deliberation, I ordered a TACT 2.2X from the local dealer (sheer luck- the ONLY hi fi store in Caracas carries Tact, and the owner's main business is industrial/commercial acoustical design and consulting).
My listening preferences run the gamut from jazz to classical to blues to pop to rock. I listen to vinyl about 60% of the time. For my Tact evaluation and set up, I relied heavily on the Chessky Demonstration disc, Holly Cole's Temptation, Jennifer Warnes' Famous Blue Raincoat, Neri Per Caso's So This is Chritmas, Jazz At the Pawnshop, Cantate Domino,and Belafonte At Carnegie Hall (all on CD).
I listen at fairly high levels (85 to 90 dB), and look for the usual qualities in a high end system, with a bias towards midrange warmth and "precise" soundstaging.
Before implementing any digital corrections, I assessed the TAC only as a DAC (with the BAT still in the system) and as a DAC/preamp. I found the TACT's 24/192 upsampling DAC to surpass the Muse's non upsampling 24/96 DAC in the areas of detail/resolution, soundstaging, and bottom end extension. Out of the box, the TACT was noticebaly brighter than the Muse, lendig a somewhat artificial character to the music, but this improved after a week of burn-in, and even more after connecting a Top Gun HCFI, Bybee Purifier, and Marigo 5.0 digital cable. Though the Muse on its own was warmer and more natural, I could live happily with either presentation.
Taking the BAT out of the system revealed the TACt to be an outstanding preamp on its own. Yes, the BAT's midrange warmth was gone, but the difference was surprisingly minor to my ears. In terms of high end extension, soundstage width/depth,and imaging the TACT was definitely in the same league. Note that at this time my amps were Aronov 9100's - the CJ's came later...
Having established the basic merits and shortcomings, I moved on to the measurement and correction stage. Measurements using the Tact's calibrated microphone confirmed that the frequency response in my room was a nightmare below 80 Hz, with peaks as high as 10 dB and holes as deep as 12 dB. Also, due to room interactions, the right channel output level was ~ 3dB higher throughout a good portion of the frequency spectrum.
My first attempts at using the TACT to correct the response were disastrous. The TACT's user manual is good only as fire kindling. It is absolutely essential to join Tact's Yahoo User's Group and pretty much read all the messages posted so far, and even better to work with someone who has climbed the learning curve already. While the Tact is capable of computing and applying correction filters to make the response curve perfeclty flat...your system may not be up for it. After trial and error, posting questions on the User Group, and 3 visits from my dealer, these are some of the generalizations I've come up with so far:
1. The TACT allows you to completely change the frequency response curve of your speakers, to enhance the midrange, to boost the bass, etc. My counsel is -- DON'T. If you force your speakers to sound/act in ways they were not designed for, they will not be happy. I did implement a mild roll-off of the very top end to tame the TACT's inherent brightness, but after playing around with various midrange and bottom end boosts I settled for a target frequency response which basically reproduced the Guarneri's natural, very linear response.
2. If you try to fill in big "holes" below 200 Hz or so, you WILL overstress the drivers in your speakers. In the end, I left the "holes" below 200 Hz untouched unless the X-over frequency placed them squarely in the subwoofer's domain. The mid/bass drivers on the Guarneri's are simply too small to deal with anything more than a 1 dB correction at these frequencies. A hole at these frequencies is barely noticeable, and far less objectionable than a either a peak or the sound of your mid/bass driver reaching its maximum extension and trying to go further!
3. Conventional subwoofers are too slow. Based on the response of my Guarneri's, the ideal X-Over frequency would have been 100 Hz, but the RELs cannot deal with this. A x-over point above 60 Hz will muddy up the bass, since the REL's cannot move fast enough to sound musical when asked to reproduce 100% of the signal in this range. This is simply not what they were designed to do.
With the X-over set between 50 and 60 Hz, the peaks removed, the holes left alone, the left and right channel levels matched by the TACT, and the sub/main response time-aligned by the Tact the result was......a revelation.
The soundstage is huge, wider than I've ever heard it. Placement of instruments and soloist withing the soundstage is tack-sharp and very well delineated. The bass is flat and tight down to 16 Hz (yes,the Stratas DO go that low in my room). The midrange is detailed and articulated as never before, now that the mid/bass drivers do not need to reproduce anything below 50Hz. The top end is super clean, very musical and detailed. Brass (e.g., in Arturo Sandoval's "Hothouse") has the proper bite and blat but is never shrill. Low level resolution has also taken a huge step up now that the sound is freed from bass colorations.
Oh...as for the midrange magic lost with the BAT...replacing the Aronov amps with the Premier 8XS has taken care of that in spades. Using Svetlana EL 34's in triode mode, the 8XS bring a palpability, presence, and warmth to the mids that is to die for..and which probably would have been too much of a good thing combined with the BAT. Althought the 8XS "only" deliver 130 watts or so a piece, they are working well within their comfort zone since they too don't need to worry about anything below 50 Hz.
Last....what does vinyl sound like thru the Tact? Pretty damned good. The A/D module on the 2.2X samples the analog signal at 24/192 and that seems to be more than enough. Yes, perhaps some ineffable "air" is lost in the process, but the improvements wrought by the correction in other areas far offset this. To be fair, the Pass XONO (which recently replaced a Linn Linto in my system) helps a lot. The XONO plus TACT combo certaily beats my Linto sans TACT, so overall I'm a step ahead.
So (as my wife asked) am I "done"??? Of curse not! I really would like to try faster subwoofers so that I can raise the X-over point to 100 Hz and "fill in" the nastiest holes in the frequency response without blowing a driver in the Guarneri's. TACT makes their own subs for this purpose, and they are certainly on my "next" list.....
Associated gear
Linn LP12 (Arkiv B, Ekos, Lingo)
Muse Model 9 Signature CD Player
Pass XONO Phono Preamp
Conrad Johnson Premier 8XS Amplifiers
Sylvania Gold Brand 5751 Tubes
Brimar/Mazda 6FQ7 Tubes
Sonus Faber Guarneri Homage speakers
2 REL Strata III Subwoofers
Audioquest Diamonond X3 Interconnects
Audioquest Dragon SE speaker cables
CPC Top Gun Power Cords
CPC Top Gun HCFI Power Cords
Marigo Reference 3.03 Signature Power Conditioner
Bybee Quantum Power Chargers
Bybee Interconnect Filters
Bybee Ultra Speaker Purifiers
PS Audio Ultimate Outlets
Mana Level 4 Compnent Rack
RPG Studio in a Box Room Treatment
2 Siamese Cats (randomly placed)
Similar products
BAT VK5i SE Preamp
Linn Kairn Pro Preamp
Linn Wakonda Preamp
9 responses Add your response
Alex: Nice job it truly shows how critical room correction is. Also, I compliment you on not trying to deal with the holes. It just doesn't work, unless it's a very small gain needed. I also appreciate your discussing our PARC with us. I wish we could have served you better in Venezula, but having a TacT dealer there, and we are just starting to distribute in South America I think you made the right choice. Dealer support (particularly abroad) is very important. The only other comment I would make is about your subwoofers. I think they are very very good, and quite musical, but I agree they do not integrate well over 50 to 60 Hz. You might consider speakers that work near flat down to 40 Hz--although I'm surprised that the Sonus Faber speakers aren't filling the bill at 100 Hz--does the room have a severe suck out at this frequency, or is it a speaker issue? |
Thank you for the kind feedback. I also wished I wold have been able to audition the PARC before taking the plunge with the TACT. As for my problems below 100Hz, these are very much room induced problems. The Guarneri's in my old room were capable of remarkably linear reposnse down to 45 Hz. In this room, I have sharp dip at 63 Hz and another one at 94 Hz, both in the 12 dB range. Further up the spectrum, I get another sharp dip of about 6 dB at 158 Hz. The rest is pretty flat indeed. The dips are symmetrical oand nearly identical on both speakers, os I think I am dealing with some nasty room issues (floor and stairwell at the lower frequencies, and perhaps the suspended plaster ceiling at 158??). Setting the X-over point at 50-60 Hz takes care of the worst of the lowest dip, since the RELs do quite well in this range, but if could X-over at 100 I would completely clena up the bottom end, and probably be able to correct part of the higher frequency dip. Given that I could not make these dips go away with repositioning, I chose to set up the Guarneri's at the optimum distance for driver integration and soundstaging. They are now 2.75 meters apart, 2.75 meters away from the sweet spot. Distance to the rear wall is close to 2 meters, and to the side walls about 1.5 meters. |
I don't see how the REL would clean it up if it's room induced. You can of course increase the output of the subwoofer, but that will muddy up everything. You would need a sub that you could increase the output at 100 Hz--this would likely give you the same problems you had with the main speakers (although to a lesser degree). What are your room dimensions? 5.75 meters wide--that's 18.87 feet which would normally give a peak at 63 Hz--unless you are sitting at a null point. What are all dimensions--and can you tell us more about a "suspended plaster ceiling"? Also, have you measured the "hole" frequencies in various parts of the room to insure they aren't just nulls at the listening position, but are truly "holes". |
OK, let me try to shed some more light. - The room is 5.72 meters by 4 meters, with 2.72 meter high ceilings. The listening seat is dead center along the long wall, and about 18 inches away from the back wall. - Backwall is treated with RPG diffusors. The first and second reflection points on the ceiling, front wall and side walls are treated with 4 foot tall RPG foam panels. The corners are treated with 4 foot tall RPG foam wedges (this is the RPG Studio in a Box kit). - The level on the subs is adjusted so that the SPL between 16Hz and 85 Hz is no more than 6 dB down vs the midrange level of the mains. This level is still about half of the way to full output on the subs.This gives two broad peaks of about 10 dB fom 35 to 53 Hz and 62 to 83 Hz, which the Tact can easily suppress. The Tact can easily boost the output between 16 and 25 Hz as well, with no ill effct on the subs that I can perceive. The subs response exhibits similar dips to the main speakers, slightly shifted in frequency due to the different positioning and acoustical environment. Both subs show a dip at 54 to 62 Hz (this dip is the one that creates the humps described above when the output level is increased). The left sub dips again at 94 Hz, while the dip on the right sub is shifted to 108 Hz. The reponse on both subs then goes up to - 6 dB (vs the midrange) at 140 Hz, at which point the subs roll off. - The ceiling seems to have been constructed by hanging a steel mesh from the actual roof (steel I beams covered with prefab slabs) using many welded steel rods. The mesh was then coated with plaster repeatedly to create this suspended plaster ceiling, which is about 2 inches thick. The space between the plaster ceiling and the concrete roof is hollow and about 18 inches deep. - I should mention that all the walls are different. Behind the speakers, it is half flimsy sliding glass windows on the left and drywall over floor to ceiling glass panes on the right. On the right, we have plastered cinderblock. On the left, we have a 4 inch mdf sandwich over structural steel stuffed with compressed fiberglass. Behind the listening seat, we have plastered brick and of course the sliding hardwood door which covers one third of the wall. On this wall, above the listening seat, there is a huge AC vent, about 8 feet wide and 18 inches tall opening into a monster AC duct. The AC unit is way overpowered, so it stays off during listening sessions. - THe sliding hardwood door opens pretty much directly onto a staircase leading down to the second floor. Althouh the door its solid, it is free floating on the rails and doe not provide a hermetic seal. - The floor is made up of very long hardwood boards nailed every half meter or so onto a grid of 2 by fours, which in turn sit directly on the underlying concrete slab floor. This creates a shallow cavity under the floor. As you can see, this room is basically a study in what NOT to do to create a good listening room. Just about every basic rule has been violated. It has, however, a few redeeming qualities: 1. Its MINE!! I can have as many cables on the floor there as I wish and my wife could not care less. 2. Its large enugh to allow the Guarneri's to be properly placed far away fom each other and the listener. My room in the US allowed only near-filed placement, and this is not how the Guraneri's show their best. 3. Its on the third floor of my apartment (OK, this is a very large penthouse apartment). All the bedrooms are on the second floor, and I have NO neighbors. So..loud music at 1 am is NOT a problem. 4. The view from the windows, which overlook the Avila mountain in Caracas is breathtaking. OK, you have to sort of kneel down to peer underneath the RPG foam panels I stuck to the windows in order to catch the view, but it IS there. :o) 5. In the room next to it (an informal dinig room opening up to the terrace) there is a full wet bar, so I can refill my scotch without walking to the kitvhen on the first floor. 6. Right outside the sliding wood door, there is a bathroom. Hope this helps! |
Alex: You haven't broken every rule. You still have at least 4 or 5 major ones you missed. But the ones you did break you did a really good job with them--crushed them more like it. I'm only kidding. Is it possible for you to take measurements in various locations in the room and see if you are in a null for those frequencies or if they are truly a "suck out" caused by the room. They are really big to be a suck out, but I can see certain positions where there could be a null. This architecture is fairly unusual as well (compared to the typical building we deal with)--I have some ideas on how it might react, but having not measured the in room response of a ceiling constructed in that way I'm not sure the theory is correct. It could be acting as a giant capacitive bass trap and could be why you have the holes (particularly the one at 94 Hz which corresponds to the room width). That's why I want to know if the 94 Hz is a null point or truly a hole. |
I will try to take some measurements this weekend. The battery on my Rat Shack is dead. I also have the German AC Fish thingy sold by the CARA folks (ordered directly from the Fatherland!) whihc I'm sure its more accurate than the Rat Shack but have, so far, not managed to figure it out. My German is nonexistent and though I have copy of the manual in English it still makes no sense to me..plus the test/calibration CD is all in German too! |