Sewer Scoping & Video Look so good!!!

I also want this!!!

Amplifier Technologies Inc AT2505 tested power output. Ok, this is another follow up on my 2ea. ATI AT2505 amplifiers. After 20 years, I decided to replaced all the 22000uf 80volt power capacitors. There are 2 capacitors per channel so that is 20 in total for the 2 ATI 2505 amps. I decided to to test the power output using some 8 ohm and 4 ohm 200 watt Dummy Load Resistors I recently purchased. These work fine for much more power as long as you let them cool. I mounted mine to some large aluminum plates for heat sinks which works well. I could not test all 5 channels at the same time as I only have 2 4 ohm and 2 8 ohm resistors The results are as follows. 4 channels driven 2 at 8 ohm and 2 at 4ohm. Results are: 8 ohm= 272 watts/ 4ohm= 424 watts. 3 channels driven ohm= 312 watts/4 ohm=517 watts. 1 channel driven 8 ohm=332 watts/4 ohm=567 watts. This is the big one. I hooked up 2 4 ohm resistors in parallel equaling 2.1 ohm measured resistance and got 800 watts just before clipping 1 channel driven. I then added an 8 ohm resistor to the 2 4 ohm to get a measure 1.7 ohm resistance. the results were 900 watts and then 1 of the 10 amp fuse of the 2 fuses per channel blew. Also not that all these measurements were done using a 40 Hz test tone from one sub output from a Yamaha DSP-A1. to hear when the amp was at clipping I had a 3.2uf 400 volt Capacitor connected to a aluminum dome which gave it a 6db crossover at 7khz. To test all the Capacitors, Extech True RMS mulitmeter and Tweeter were connected to the channel being tested. When the amps begin to clip the tweeter begins to "BUZZ". Just past this point the clipping indicator lights on the ATI 2505 amp begin to light up. This is a proven method to test without spending bunches of money on test equipment. To see how this is done look up this youtube video: Detect amplifier clipping WITHOUT DD-1! Cheap simple clip detector

Bought one used on ebay for $1000 and the other New for $2200.

This is just an update to say that these 2 each ATI AT2505 Amps are still working flawlessly and have been used at least 5 days a week since I first purchased them. 15 years ago and still going strong. I Love these amps and will not part with them. These are just a bullet proof superb sounding product by a first rate manufacturer.

I have now owned two of these ATI 2505 Amplifiers for 9 years and they have always worked flawless. If anybody has problens with "HUM" be sure to use a a ground lift adaptor or cut off the ground prong on the power cord plug. Your audio system should never haver more than one grounded component because it will usually cause a ground loop "HUM".
I would happily purchase these amplifiers again.
5 Stars again
Dan L.

very impressed with the sound. The ability of this amp to reproduce the full impact of 5 channel movie soundtracks Even at relatively moderate listening levels this amp is absolutely incredible at revealing ever natural and detail. This is the kind of power needed for an involved home theater set up. .You will love the quality of NATURAL SOUND .. At higher volumes, it never really seems "loud," but it is...it's just so clear! really rocks! In "The Haunting," it felt like it was my own house that was collapsing around me! I'd have to say that you'd have to spend a lot more money to achieve a better sounding amp for the money. It's just beautiful. Music CDs I've heard many times never sounded better. I love this amp!

This amp is for those who want the best sounding multi channel amplifier and one of the best musical sounding amps as well. Clean sound, tight extended bass, powerful enough to move almost any speaker without a problem. Not much to say, this is one of the best sounding multi channel amplifier period. If you mostly listen to music but want something that does movies as well then this is a great choice. Built like a tank.

big open sound stage, detail, great value, smooth

none at this price

Associated Components: Speakers: Center: Martin Logan Cinema, Front (left/right): Martin Logan Ascent, Surround Rear: Martin Logan Scenario Subwoofer: Infinity HPS-1000 (1000 watts) Speaker wire: Audioquest GR 8 Interconnects: Nordost Blue Heaven Processor: Rotel RSP 1066 CD player: NAD 541i DVD/CD players: Pioneer Elite DV-c36 and Sony NC 650V SACD/DVD/CD Player. Power Conditioner: Monster Cable HTS-1000. I am blessed with a good career but I am not wealthy so I really had to select well on this purchase. I am in search for an amplifier that conveys music and movies accurately. In my quest, I auditioned Sherbourn 5/5210, Classe’ CAV-180, Krell (entry level), Outlaw 755, Rotel RMB-1095, and Pass Labs X5. The Sherbourn 5/5210 was powerful and dynamic enough for home theater applications but under performed with music. It sounded as if it was struggling to drive the Martin Logans. Martin Logans are definitely not ideal for the Sherbourn 5/5210. The Krell sounded great but it was a bit expensive for what you get. The Outlaw 755 is a good amplifier that could drive the Martin Logans. It sounded open but had an edge in the upper frequency. It was entertaining and a good choice but I was still not satisfied. The Classe’ CAV-180 was an outstanding choice. It reminded me of a very high-end amplifier. It is a relative bargain for $4000 but I was not willing to gamble on lack of dealership support in Arizona. The local dealer here had Rotel RMB-1095. This is a highly regarded amplifier as well. It was recommended in Stereophile and other periodicals. My impression was that it was smooth sounding and dynamics were respectable too. The bass was its shortcoming. It could not produce music with complex bass. I wanted to like the Rotel so much because it was affordable but it just did not address my needs. The Pass Labs X-5 is also a great candidate. This amplifier is popular choice but lacked the power I needed. Finally, I auditioned the ATI-2007. This was highly recommended by Art Brett of Brett Interiors (520-733-9896), a hi-fi dealer here in Tucson, Arizona. I must admit I did not really know ATI, but I decided to give it a try since the dealer seemed trustworthy and knowledgeable. To my surprise, this amplifier sounded great out of the box. It did not have the edge of the Outlaw and sounded smooth also like the Rotel. It sounded like the Classe’s CAV-180 but it was just $1000 cheaper in a 7-channel version. The Classe’ was very good indeed but it was hard to justify $4000 investment where you can buy the ATI-2007 for $3000 with more power and more channels. This amplifier is a profound bargain for $3000. Its dynamics, bass reproduction and mid-range frequency were impressive for the money. Voices sounded natural and instruments are well-spaced. The sound is big and effortless. I loved it the moment I connected it and I continue to appreciate its talents each passing day.

Similar Products Used:

Krell, Outlaw, Sherbourns, Rotel, Classe, Pass Audio

powerto deliver bass and clarity and imaging.

weight, requires it's own 20 amp circuit, and won't accept spade lugs.

Scary power, the best placement of sounds (imaging) I've heard, beautiful midrange and powerful bass. I'm sure this amp is impossible to beat for home theater and difficult to beat for music. It's weight at 106 lbs. is monstrous but makes you feel that this amp is indestructable, which it probably is. I love the auto on feature which integrates with my Lexicon processor perfectly. It drives ribbon and planar-magnetic speakers which sound better than before. It completed my home theater. I use an Oddessey (150 wpc) amp for the two rear speakers (7.1 system.) This set up with a Sunfire Signature sub simply makes the room rumble and shake yet, any slight sound is heard with clarity and precisely placed where it should be. Mine was an opened box last of it's kind special but, even at $2,000 or more, it's a deal.

Similar Products Used:

Oddessey, Audio Research, Yamaha, AMC, etc.

Need help just got my ATI 2505 and having problems with HUM. Ran a 20 amp circuit to power amp and other components using a Denon AVR-5800 as preamp #1 problem HUM In all speakers #2 problem after diconecting all the inputs have a loud HUM in the left channel only ruled out speaker by testing with another speaker useing Monster Cable Interlink 400 Mk II please help.

Solid Build. Incredible power reserve. Great soundstage.

none that can be found.

I was very skeptical about going to a separate power amp. Thanks to the reviews of others here, I took the chance and I must say that it was a great move on my part. My excellent Pioneer VSX-27TX Receiver is now a preamp/processor. Although it pumped out clean power to all channels, it was no comparison to the ATI-2505. I am getting bass response out my Polk RT 800's like never before and believe me, those speakers love power! Like others, I am listening to my music and movie collection all over again, hearing things I've never heard before, with crystal clarity and presence. Sure, I would be naive to think that other power amps wouldn't do the same but this baby cranks with absolutely no effort. Take a chance on the low price and the generous wattage you get, great build quality and a manufacturer that stands behind their workmanship, 7 years worth, along with modular replacement capability. This amp will satisfy my need for power for a very long time! Thank you, ATI!!!

Similar Products Used:

none. (first timer!)