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Titanium Dome
05-07-2011, 07:31 PM
I had business in Alhambra, CA, which is north of Montebello, CA, home of Amplifier Technology, Incorporated, or ATI. My meeting ended early, so I decided I'd try to find the ATI factory and see what's going on there. It wasn't the easiest quest in the world, and once my GPS got me to the address, I still couldn't figure out if I were in the right place or not.

Eventually, asking questions of nearby corporations and persistence and a little exploration paid off, and I was inside ATI.

Over the course of several posts, I'll explain what transpired there. The end result: I've got two brand new ATI amps driving my K2 S9900s, and I love them. :yes: :bouncy: :yes:

HCSGuy
05-07-2011, 09:14 PM
I remember working the Stereophile show with Mike Pontelle and Morris Kessler way back when they launched the brand. We had a AT1606 open on the table (it was a static display only) and it blew people away just by the construction - the huge toroid transformer, which they wind themselves, super clean board layout, and almost no point to point wiring. If you opened up a Parasound or B&K in those days, you saw yards of loose wires going this way and that. In the case of B&K, you also had two fuses for each channel, on the boards inside the amp. I think I had a Hafler XL600 at the time, and when I opened it up to compare, it looked DIY by comparison.

I also toured the ATI factory at the time; they still had a stack of old SAE parts in racks that was about the size of my house (I'm not kidding), and one guy at a bench in the corner still fixing them. I am fairly confident that you will not replace these amps in your lifetime due to failure - they are a proven design, very well executed. Good choice, though you may not be able to brag about them to your audiophile friends...

edgewound
05-07-2011, 09:49 PM
I had business in Alhambra, CA, which is north of Montebello, CA, home of Amplifier Technology, Incorporated, or ATI. My meeting ended early, so I decided I'd try to find the ATI factory and see what's going on there. It wasn't the easiest quest in the world, and once my GPS got me to the address, I still couldn't figure out if I were in the right place or not.

Eventually, asking questions of nearby corporations and persistence and a little exploration paid off, and I was inside ATI.

Over the course of several posts, I'll explain what transpired there. The end result: I've got two brand new ATI amps driving my K2 S9900s, and I love them. :yes: :bouncy: :yes:

ATI acquired the assets of BGW when it closed down.

DavidF
05-08-2011, 10:24 AM
ATI acquired the assets of BGW when it closed down.


And most recently did the same with B&K Components Ltd.

Siefreid Linkwitz recommends ATI amps among others and has used them on demos of his active xover designs.

http://www.audiogon.com/cgi-bin/ces.pl?linkwitzlab&&ManuView&&&&&&&RMF08

HCSGuy
05-08-2011, 10:43 AM
And they bought Theta a couple years ago (and bought the SAE name back some time ago)- don't know what they're going to do with all of these...The basic ATI amp business, while not that exciting (no new technology story), is stable, the designs are good, the amps are extremely reliable - in short, a pretty good business model for a private company that wants to stay profitable but isn't trying to conquer the world. I don't know what BGW brings, but Theta and B&K both bring serious support issues, as both had quasi-upgrade programs with continual re-engineering to keep their older models workable. I think those programs are all gone, and I don't see Theta coming back - it requires a big company to engineer a current HDMI equipped processor, and even with all these brands I don't think they have the market to do it. And buying up brands just for the power amplifier share doesn't make sense either - B&K ruined their own name, why spend money to resurrect it? Morris Kessler has been in the business long enough, and has been successful enough that he is entitled to whatever Bob Carveresque brand exploration he wants, I just think all of these bought brands need a huge investment to re-establish themselves, which I don't think they're all going to get.

Anyway, back on topic - enjoy the amps!

SEAWOLF97
05-08-2011, 11:33 AM
most nfo on the web doesnt answer my question:

"When BGW went out of business, Barbara Wachner sold it to ATI (Amplifier Technologies Inc). ATI purchased the assets of BGW Systems. Morris Kessler (Mr. ATI) hired Steve Lyle who was the last engineer from BGW."

did ATI just purchase BGW's inventory or the intellectual design rights too ? How close were BGW's designs and ATI's after purchase ?

the web does note tho that the newer BGW gear doesn't measure up to the 1980's offerings.

Titanium Dome
05-08-2011, 12:07 PM
The south side of Montebello is a commercial and industrial area with the typical dead end streets, missing street signs, security gates, huge fences, clogged truck traffic, fork lifts in the road, hard to find addresses, etc. My usually trusty GPS guided me through all this and took me to the address I gave it.

I found a place to park, went to what I supposed was the front door since there were no signs, but there was an address on the building, and I tried to enter. Locked. No bell or buzzer. Knock, knock, knock, knock... no answer.

After six or seven minutes, obviously no one was coming. I drove to the building next door and asked,"Is this ATI?" "No, it's over there," pointing to where I'd just been. "Thanks."

So I drove back, walked around a bit, knocked on the door again, then noticed the loading dock was wide open. I walked over to the big dock and called out, "Hello? Hello? Anyone here?" No answer.

I noticed a pallet of JBL Synthesis« amps, some Crestron stuff, Theta, B&K, and more. Since I didn't think companies like you entering unannounced through the warehouse, I waited and called some more. Eventually a friendly worker came over with a big pallet of Crestron amps and invited me to climb up the stairs to the factory floor, where he talked to someone who talked to someone who took me deeper inside.

SEAWOLF97
05-08-2011, 12:30 PM
The end result: I've got two brand new ATI amps driving my K2 S9900s, and I love them. :yes: :bouncy: :yes:

so, what got replaced & improved upon ?

Titanium Dome
05-08-2011, 12:30 PM
Through some doors, down some hallways, past offices and rooms, eventually I ended up in a room chock full of Theta CBIII units getting upgraded to HD. It was in fact stunning to see inside these venerated units, bristling with cards and slots, and seeing the new cards that were going in to upgrade these beautiful units. While the Casablanca is outside my interest and price zone, it's amazing nonetheless that ATI is following through on keeping these long-lasting beauties current. Those who bought earlier CBs and followed the upgrades over the years spent some $$$, but this is a case where the manufacturer really kept its word on upgradability.

There I met Jeff and Jordan, busy with these and other tasks, including working on a Theta Intrepid amp and, what's that, a JBL Performance Series AVA-7 I see? I have one of those. :p

They took the time to listen to why I was there, what I had, what I'd already tried with the K2s, what I liked/didn't like, why I was interested in the amps they produced, etc. They have some knowledge of Levinson, Krell, Parasound, Bryston, McIntosh, Pass Labs, etc., so there was some interesting discussion.

What I wanted:

First class build quality
plenty of power to drive and control the efficient K2s
long warranty and available service
ability to deliver full power across the full bandwidth with all channels driven
ability to run off one dedicated 20 Amp circuit without tripped breakers and whole house brown outs
balanced inputs
remote triggers


What I did not want:

expensive billet faceplate adding $$$$ to the price
proprietary, hard-to-find connectors
big power ratings that only apply to one channel at 1kHz
fans
a plethora of lights or illuminted meters or Cylon-inspired eyes
220-230V circuit requirements
shelf-scratching, floor-scratching, or component-scratching sharp feet
enclosure colors or finishes that demand attention: "Look at me!"
jewelry

Mr. Widget
05-08-2011, 01:13 PM
And they bought Theta a couple years ago (and bought the SAE name back some time ago)- don't know what they're going to do with all of these...They also bought Audio Access from Harman... for those who don't know, Audio Access was a brand that made excellent sounding though expensive distributed whole house audio systems and were slow to keep up with their industry and became rather obsolete... ATI seems to like buying good but rather obsolete brands.


so, what got replaced & improved upon ?He hasn't finished describing the loading dock... be patient he'll eventually get to the point. ;)

Congratulations Dome... the ATI stuff is very good quality gear with no frills or wasted money spent on glossy ads or machined face plates. So, did you get the 2000 series or 3000 series? I guess I need to be patient too? :banghead:


Widget

Titanium Dome
05-08-2011, 02:55 PM
He hasn't finished describing the loading dock... be patient he'll eventually get to the point. ;)

Congratulations Dome... the ATI stuff is very good quality gear with no frills or wasted money spent on glossy ads or machined face plates. So, did you get the 2000 series or 3000 series? I guess I need to be patient too? :banghead:


Widget

You know the author. :p

Titanium Dome
05-08-2011, 03:12 PM
Based on my wants, we tended to go in two directions, both ending with ATI, either the 2000 Series or the 3000 Series. There were some exceptionally nice amps from the Theta line, but they had too many things that were on my don't want list, plus the biggest deterrent of all: price.

In fact, to characterize this long process in a few words: I don't want to waste money on an amp.

There are a lot of high end, beautiful looking amps that are amazing, but they aren't so amazing that their cost is justified to me. Somewhat like a beautiful woman (or man), the beauty only takes you so far, then you really have to deal with what's inside. High maintenance, high demand relationships with amplifiers just aren't on my to-do list.

In order to avoid a :flamer: war about various amps that many of us think are the best, I'll just skip the analysis and opinions expressed during the free flowing discussion at ATI. I will write that on the inside these amps are beautiful, and being able to see the internal assembly compared to some of the more expensive amps I tried was eye-opening! I've looked into amps costing many times more that looked like an explosion in a spaghetti factory by comparison.:eek: Just a final comment: Parasound and Bryston were real contenders, too, but some of the more revered amplifier brands were not on the final list. (See my don't wants above, and you'll know why.)

What was surprising was the final verdict was in favor of the 2000 Series, rather than the more powerful and expensive 3000 Series. I eventually left with two ATI 2003 amps. That's 3 x 200W.

Each amp drives a K2 and an S2S sub, so 200W to the K2 HF/UHF inputs, 200W to the K2 LF input, and 200W to the S2S. While technically this is the same power to the K2 and less power to the S2S than I was using before, it's clear that not all power ratings are equal.

Wardsweb
05-08-2011, 06:08 PM
I flew out there about 10 years ago and met with Morris. He let me go through the whole room of stacked SAE boxes and pick out what I wanted. I ended up buying a whole pallet of gear. He showed me his first SAE amp built in his bedroom. It was real DIY piece. Then he showed me several items that never made it to production and a amp he was building for Outlaw Audio. It has optically isolated outputs. Short the outputs only put it into protection. Remove the short and the amp started playing again. The guys on the warehouse floor were assembling Adcom amps at the time, right along side one of Morris' Ferrari's.

Titanium Dome
05-08-2011, 06:40 PM
The quick set up at home was with single-ended RCAs from the pre to the amps. With the trigger cables installed and the amps plugged in, it was a breeze to get started.

The Outlaw 990 I'm using has two triggers out: perfect. The ATI's "pure balanced" architecture includes soft startup, so there's no tripped breakers or brown outs in the house. The giant, twin toroidal transformers in each enclosure provide impressive capacity and stability. Each unit can be configured with up to seven channels, so these are big transformers.

My first impressions were of a deeper, wider soundstage, improved localization within the soundstage, notably better bass, and a sonic character that within minutes seemed so annoying and fatiguing that I literally wanted to box them back up and throw them through ATI's front door. (You know, the locked one.)

Perhaps the fact that they're way over 100 pounds boxed and my back already hurt kept me from doing that, so I retired, disappointed and frustrated. And embarrassed.

All the next day, I pondered what to do. I even polled some of my AVS buddies to see if they had any ideas, but they were all traditional cures like lower the treble, get an EQ, buy warmer amps, get better cables, use a tube pre. So at the end of the day, I was still :wtf: about the whole thing.

One guy had mentioned "breaking them in." Being an agnostic in the whole burn in religious war, I didn't think much of it. I always thought it was more listener adjustment that equipment transformation. But I was desperate, so I loaded in one of the most annoying disks I have and ran it all day. When I came home, I turned it off, worked out downstairs, watched a movie with Huiky, and went to bed.

Titanium Dome
05-08-2011, 07:02 PM
The next day, a Saturday, I reconnected the amps using balanced XLRs. Luckily, the 990 has two balanced sub outs.

I put on the heretofore annoying disk, Vital Idol, and was struck by how much better it sounded. In fact, it sounded fantastic. I switched back and forth between analog audio bypass (Oppo BDP-83SE analog out to the CD inputs) and digital in (Oppo via optical cable out to DVD inputs) and really couldn't discern any difference. They both sounded great, and I listened to the whole darned CD without flinching my ears once.

Then I tried classical, dance, acoustic guitar, the ever faithful Heart "The Road Home" live set, jazz, Buble, Groban, Sade, Keys, Lady Antebellum, Beatles, ... couldn't find a thing that didn't sound wonderful.

Did the amps change? Did I change? Did the balanced cables make the difference? Don't know; don't care. Don't plan to spend time worrying about it. The amps are effortless, boundless, silent workers creating high quality amplification with no fuss or bother. This camper is happy! :D

So there it is: Made in CA amps with a seven year warranty attached to Made in CA speakers with a five year warranty. If I could find a Made in CA pre and a Made in CA source that I both liked and could afford, well wouldn't that be something?

Uncle Paul
05-09-2011, 06:06 PM
What I wanted:

First class build quality
plenty of power to drive and control the efficient K2s
long warranty and available service
ability to deliver full power across the full bandwidth with all channels driven
ability to run off one dedicated 20 Amp circuit without tripped breakers and whole house brown outs
balanced inputs
remote triggers


What I did not want:

expensive billet faceplate adding $$$$ to the price
proprietary, hard-to-find connectors
big power ratings that only apply to one channel at 1kHz
fans
a plethora of lights or illuminted meters or Cylon-inspired eyes
220-230V circuit requirements
shelf-scratching, floor-scratching, or component-scratching sharp feet
enclosure colors or finishes that demand attention: "Look at me!"
jewelry



Those are great lists with a lot of practicality and thought behind them. The images on the website don't really show a lot, so I downloaded the brochure. They most definitely meet your criteria above in all respects. The pix in the website make them look very industrial, but the closeups in the brochure show the face plates to be quite attractive, just not flashy.

Titanium Dome
05-09-2011, 10:29 PM
Those are great lists with a lot of practicality and thought behind them. The images on the website don't really show a lot, so I downloaded the brochure. They most definitely meet your criteria above in all respects. The pix in the website make them look very industrial, but the closeups in the brochure show the face plates to be quite attractive, just not flashy.

The first time I saw the brochure was in the packet of materials that came inside the sealed box. I tossed it aside at first, but looked at it the other day and was fascinated by "An Interview with Morris Kessler" and "ATI Manufacturing: No Shortcuts, No compromises"

There's a picture there of the transformer winding rig and a bunch of the transformers. Look at the worker's hand to get a sense of the size of the rig. You could put your head inside it--not that I'd recommend it. ;)

For interested parties: http://ati-amp.com/manuals/ATI_Brochure_2005.pdf

Wardsweb
05-10-2011, 08:28 AM
There's a picture there of the transformer winding rig and a bunch of the transformers. Look at the worker's hand to get a sense of the size of the rig. You could put your head inside it--not that I'd recommend it. ;)

For interested parties: http://ati-amp.com/manuals/ATI_Brochure_2005.pdf
I saw them running transformers when I was there. The guy placing taps while it was running was good. You have to be precise and quick, or loose a finger.

Uncle Paul
05-10-2011, 04:10 PM
I ran across a store front that had retail prices listed - not cheap, but one helluva value.

Almost afraid to ask, because the answer likely to cost me $$$$ - do you think this amp would be a good match sonically for a mere XPL-200A?

BMWCCA
05-10-2011, 05:55 PM
I ran across a store front that had retail prices listed - not cheap, but one helluva value.

83% off (http://classicaudioparts.com/store/ati-factory-authorized-items-for-sale.html) looks like a good deal. No HDMI??

hjames
05-10-2011, 06:42 PM
83% off (http://classicaudioparts.com/store/ati-factory-authorized-items-for-sale.html) looks like a good deal. No HDMI??

That's what had me leery about ATI last time TiDome mentioned their Pre/Procs on killer sale last year,
I think it was around the time I shipped that funky Emotiva UMC-1 back.

Its probably fine for pure music only use, non-DVD and that sort of thing - but I was hesitant to rush into anything without HDMI at this date -
no HDMI was a deal breaker for me, for sure! And with the bad-acting HDMI in the Emotiva - I had already risked being burned once.

Uncle Paul
05-10-2011, 07:21 PM
I finally came to the conclusion that I need to keep 2 channel and HT somewhat separate in order to enjoy both. When my home addition is complete and I can hook everything back up, I'm going to use a HT receiver for TV & movies and my separates for 2 channel service. I'm going to run R & L outputs from the AVR to my 2 channel preamp and thus to my XPL200A's. Its the best compromise I can come up with that doesn't use two completely separate systems. 2 channel is my main interest and where I'm willing to spend more.

At some point in time there will be processor I can afford that will give me the features I want as well as the 2 channel quality I desire. As soon as that happens, HDMI will be made obsolete by the industry and it will start all over again.

Titanium Dome
05-10-2011, 10:45 PM
So many variables...

My XPL200As are running active bi-amp using the DX-1 Greg Timbers built for me through a Citation 5.0 to Hafler SR2300 pro amps. Since the DX-1 and Citation are single-ended RCAs, I have to use an adapter to hook up the Haflers. The source is a Denon DVD 2900 used as an analog stereo out. It sounds great!

The K2s are passive bi-amp running through an Outlaw 990 in bypass mode fed by an Oppo BDP-83SE using the upgraded analog outs and the sub out. The Outlaw outputs L, R, and two subs via balanced outs to balanced ins on the ATIs. The L and R have balanced Y cables. It sounds great!

Now, If I put the ATis on the XPL200s... :hmm: then I'd have to buy more ATI amps.

I guess in a way I'm saying that old pre-pros with superior analog stages work great in my experience, even if the surround processing and fake ambience modes are never used again. Plus, they'll both accept phono, and external DACs, and rainbows and unicorns.

Mr. Widget
05-11-2011, 11:08 AM
Plus, they'll both accept phono, and external DACs, and rainbows and unicorns.Hey Dome, next time you are up here I could use a hand getting my rainbows and unicorns phase coherent.

On a slightly more serious tack, I agree about the better pre-pro analog comment, though if one is going two-channel, a real two channel preamp with an even better analog design is probably the better answer. There are plenty of really excellent 2 channel preamps out there and some are surprisingly affordable.


Widget

BMWCCA
05-11-2011, 03:20 PM
There are plenty of really excellent 2 channel preamps out there and some are surprisingly affordable.Would it be considered off-topic if you were to elaborate and name names? Especially if they have remote capability. ;)

SEAWOLF97
05-11-2011, 04:02 PM
did ATI just purchase BGW's inventory or the intellectual design rights too ? How close were BGW's designs and ATI's after purchase ?

the web does note tho that the newer BGW gear doesn't measure up to the 1980's offerings.

nobody has an answer, I started searching and didnt find it, but this was interesting

"BGW is also an outstanding OEM supplier to many leading firms including NASA, the U.S. Navy and 3M Corporation, for whom we have designed and manufactured special audio amplifiers and customized computer systems."


so, what got replaced & improved upon ?



He hasn't finished describing the loading dock... be patient he'll eventually get to the point.
Widget

guess not


I finally came to the conclusion that I need to keep 2 channel and HT somewhat separate in order to enjoy both. When my home addition is complete and I can hook everything back up, I'm going to use a HT receiver for TV & movies and my separates for 2 channel service. I'm going to run R & L outputs from the AVR to my 2 channel preamp and thus to my XPL200A's. Its the best compromise I can come up with that doesn't use two completely separate systems. 2 channel is my main interest and where I'm willing to spend more.


in my HT there is only room for 1 large pair of mains , but movie watching is in a different spot than 2 channel listening ...hated readjusting the AVR to listen to 2ch music.

I now have the AVR & Adcom system sharing the mains.....bought a 4 set speaker selector box , but only have the one pair hooked to it....the box's value is that it will take and switch 2 amps.
So ONLY the 2 main channels of the 7.1 go to the box , along with the 2 of the Adcom , works like a charm :D:bouncy:

Mr. Widget
05-11-2011, 11:12 PM
Would it be considered off-topic if you were to elaborate and name names? Especially if they have remote capability. ;)It is and we have several threads on this topic... ;)


Widget

Titanium Dome
05-15-2011, 09:59 PM
Hey Dome, next time you are up here I could use a hand getting my rainbows and unicorns phase coherent.

On a slightly more serious tack, I agree about the better pre-pro analog comment, though if one is going two-channel, a real two channel preamp with an even better analog design is probably the better answer. There are plenty of really excellent 2 channel preamps out there and some are surprisingly affordable.


Widget


It is and we have several threads on this topic... ;)


Widget


I'd say it's time for a new thread on preamps then.

http://www.audioheritage.org/vbulletin/showthread.php?31087-Stereo-2.1-Preamps&p=313267#post313267

EDT: :wtf: There's no preamp or pre/pro forum? Okay, Miscellaneous I guess. :dont-know:

Allanvh5150
05-16-2011, 12:16 AM
I had to chuckle when I read the brochure, in particular, the part describing how the ampifiers are fully ballanced. One side does the positive part of the waveform and the other side does the negative.....really?

:)

Eaulive
05-16-2011, 03:59 PM
I had to chuckle when I read the brochure, in particular, the part describing how the ampifiers are fully ballanced. One side does the positive part of the waveform and the other side does the negative.....really?

:)

Actually that's true.
In a balanced line there's two signals of equal amplitude 180║ apart. Usually one is labelled "+" and the other one "-", even if their respective voltage can go from positive to negative against each other.
In a normal amplifier, these two signals are summed and turned into one signal which has it's amplitude related to ground, or neutral, this signal is then amplified and deliverd to the speaker through the red binding post in the back, the black one is the neutral, chassis, or ground.

In those amplifiers, if I understand well, there is one amplifier for each of the signals and these signals are fed to the speaker directly, none of the binding post is grounded and both carry voltage, kind of like a bridged amplifier.

At least that's what I make of it.

I'm not saying it's better either ;)

Titanium Dome
05-16-2011, 07:50 PM
I had to chuckle when I read the brochure, in particular, the part describing how the ampifiers are fully ballanced. One side does the positive part of the waveform and the other side does the negative.....really?

:)


Actually that's true.
In a balanced line there's two signals of equal amplitude 180║ apart. Usually one is labelled "+" and the other one "-", even if their respective voltage can go from positive to negative against each other.
In a normal amplifier, these two signals are summed and turned into one signal which has it's amplitude related to ground, or neutral, this signal is then amplified and deliverd to the speaker through the red binding post in the back, the black one is the neutral, chassis, or ground.

In those amplifiers, if I understand well, there is one amplifier for each of the signals and these signals are fed to the speaker directly, none of the binding post is grounded and both carry voltage, kind of like a bridged amplifier.

At least that's what I make of it.

I'm not saying it's better either ;)

Even though I have a fully dedicated 20 Amp circuit for the K2 system only, I could always hear a low 60 Hz hum through the speakers at idle. I noticed that when I put balanced amps in the system it diminished. With the ATI "fully balanced" architecture, it disappeared. Since it bothered me A LOT, it was a key factor in choosing the ATI over more expensive brands, along with all the things already mentioned above.

Fortunately, the old Outlaw 990 allows balanced outs to balanced ins on the ATI. It is not a subtle difference in background noise and noise floor.

Now if I could get the damn refrigerator and Radon evacuation system to be silent, I'd be all set. Oh, and those contemptible neighborhood dogs, and the traffic, and the boats in the harbor, and the wind, and...

Audiobeer
05-16-2011, 07:56 PM
What is the street price for a new AT 3000 series with 2 channels?

Titanium Dome
05-16-2011, 10:12 PM
What is the street price for a new AT 3000 series with 2 channels?

http://classicaudioparts.com/store/ati-factory-authorized-items-for-sale.html

I have to say, these prices are higher than a couple of weeks ago. In the case of the 3002, I'm thinking it's at least a couple hundred bucks more, though the full retail price is the same.

Allanvh5150
05-16-2011, 11:21 PM
Actually that's true.
In a balanced line there's two signals of equal amplitude 180║ apart. Usually one is labelled "+" and the other one "-", even if their respective voltage can go from positive to negative against each other.
In a normal amplifier, these two signals are summed and turned into one signal which has it's amplitude related to ground, or neutral, this signal is then amplified and deliverd to the speaker through the red binding post in the back, the black one is the neutral, chassis, or ground.

In those amplifiers, if I understand well, there is one amplifier for each of the signals and these signals are fed to the speaker directly, none of the binding post is grounded and both carry voltage, kind of like a bridged amplifier.

At least that's what I make of it.

I'm not saying it's better either ;)

Not Kinda like, it is a bridged amplifier. Heaps of advantages, power supply voltage a lot lower so can be made with inexpensive parts, input noise is reduced dramatically, double the slew rate......the list goes on.

Eaulive
05-17-2011, 02:54 PM
Not Kinda like, it is a bridged amplifier. Heaps of advantages, power supply voltage a lot lower so can be made with inexpensive parts, input noise is reduced dramatically, double the slew rate......the list goes on.

A normal amplifier in bridge mode does not keep the integrity of the signal throughout.
It takes the balanced input, sums it and then passes it unbalanced through the low level circuitry and attenuators, THEN re splits it into two signals of opposite polarity before amplifying them.
That's why I say "kinda like" ;)

Allanvh5150
05-17-2011, 10:16 PM
A normal amplifier in bridge mode does not keep the integrity of the signal throughout.
It takes the balanced input, sums it and then passes it unbalanced through the low level circuitry and attenuators, THEN re splits it into two signals of opposite polarity before amplifying them.
That's why I say "kinda like" ;)

Depends what sort of amplifier it is. I have amplifiers here with balanced inputs with a phase spliter directly after and then into the maine amp circuit. Balanced in balanced out when running in bridge mode.

Eaulive
05-18-2011, 05:24 AM
Depends what sort of amplifier it is. I have amplifiers here with balanced inputs with a phase spliter directly after and then into the maine amp circuit. Balanced in balanced out when running in bridge mode.

Maybe, I don't see why it couldn't be possible, but I never saw any, and I fixed quite my share of amplifiers in my life ;)

What's the brand of the one you talk about? Seems like an interesting design.

DavidF
05-21-2011, 09:31 AM
The next day, a Saturday, I reconnected the amps using balanced XLRs. Luckily, the 990 has two balanced sub outs.

I put on the heretofore annoying disk, Vital Idol, and was struck by how much better it sounded. In fact, it sounded fantastic. I switched back and forth between analog audio bypass (Oppo BDP-83SE analog out to the CD inputs) and digital in (Oppo via optical cable out to DVD inputs) and really couldn't discern any difference. They both sounded great, and I listened to the whole darned CD without flinching my ears once.

Then I tried classical, dance, acoustic guitar, the ever faithful Heart "The Road Home" live set, jazz, Buble, Groban, Sade, Keys, Lady Antebellum, Beatles, ... couldn't find a thing that didn't sound wonderful.

Did the amps change? Did I change? Did the balanced cables make the difference? Don't know; don't care. Don't plan to spend time worrying about it. The amps are effortless, boundless, silent workers creating high quality amplification with no fuss or bother. This camper is happy! :D

So there it is: Made in CA amps with a seven year warranty attached to Made in CA speakers with a five year warranty. If I could find a Made in CA pre and a Made in CA source that I both liked and could afford, well wouldn't that be something?

T D, do you find the amps running moderately warm or decidedly warm at idle? My old mosfet B&K is decidedly warm running on rather high bias and does not fit summer use too well. Looking for a cooler option. Thanks...

Titanium Dome
05-21-2011, 02:02 PM
T D, do you find the amps running moderately warm or decidedly warm at idle? My old mosfet B&K is decidedly warm running on rather high bias and does not fit summer use too well. Looking for a cooler option. Thanks...

Hi David. Nice to see you.

The ATI 2000 and 3000 Series amps have a big chassis. It's meant to hold up to seven 200 or 300 Watt amp modules. With only three modules in mine, they were installed one on the right, one on the left, and one in the center, so there's two empty slots between them.

I've run them pretty hard a few times, and the heat is negligible in that set up. Putting my hand right on the case above a module reveals some warmth, but I wouldn't call it hot. The Hafler SR amps I have (with internal fans) get much, much hotter.

The amps are in standby mode all the time. With a trigger cable (included) plugged into the DC trigger receptacle, the rear on/off switch and the front power switch are both left in the "On" position, and when the trigger sends a signal it starts powering up the amp through some soft start process. I can play music right away, but it's a few seconds before the amber light turns green. Grumpy tried to describe to me what's happening, but I got distracted by a squirrel on the deck rail outside and kind of missed it. :p

I guess the green light means "phasers at full power."

grumpy
05-21-2011, 03:43 PM
Grumpy tried to describe to me what's happening, but I got distracted by a squirrel on the deck rail outside and kind of missed it.

The funny thing is that's precisely what happened :rotfl:

I was guessing that a resistor in-line with the power transformer was being shunted
(shorted across) by a time-delayed relay... and this was both the 'click' and change
in LED status from stand-by to operate. Such a scheme reduces the initial in-rush
current associated with using large toroid transformers (keeps circuit breakers from
unnecessarily popping and the room lights from dimming :)).

Allanvh5150
05-22-2011, 12:55 AM
The funny thing is that's precisely what happened :rotfl:

I was guessing that a resistor in-line with the power transformer was being shunted
(shorted across) by a time-delayed relay... and this was both the 'click' and change
in LED status from stand-by to operate. Such a scheme reduces the initial in-rush
current associated with using large toroid transformers (keeps circuit breakers from
unnecessarily popping and the room lights from dimming :)).

Wouldnt it be nice to use real power straight from the wall.....mm mm mm. 240V stock standard here.:)

Titanium Dome
07-06-2011, 08:37 PM
So ATI's got a new look to its Web site, and I was contacted by them for permission to use my post over at AVS where I was I was peeing all over my leg in excitement about the AT2003 pair I picked up.

I'm the ATI's "True Balance" Differential Design Architecture quote near the middle of the page. Old AVSer and new Lansing Heritage member penngray is quoted right below me.

http://ati-amp.com/reviews.php

Titanium Dome
07-06-2011, 08:45 PM
There's also a little, downloadable PowerPoint presentation that shows some of the assembly floor activities.

As seen in the photos, everyone I met there seemed happy and helpful once I found my way in.

RayJr
08-19-2011, 12:58 PM
ATI builds Solid , Quality AMPS.
I have had an AT3007 for about 2 years and loved every moment of it.
This AMP drives my Home Theater for hours with out even getting much over warm.
If I had to do it all over....I would buy an ATI AMP again in a heart beat....Great product.


52551

Just my $.02
RayJr