I have had many amplifiers over the years but the 9440A's are the best sounding amplifier I have ever heard. I don't know what words to use but every sound whether it be gentle music or full blown action movies is as clean and pure as if the performance or action were live. I have also replaces my preamp. I was using a preamp with all of the bells and whistles that tended to alter the sounds from natural. I am now using the Technics SH-AC500D. The unit is probably 10 to 15 years old. I found one that had never been used. It is a "Digital Surround Processor". It doesn't do anything except decode the surround (Dolby, Dolby Digital and DTS). It doesn't equalize, no tone controls, no special hall settings but it allows the setting of large or small speakers and individual channel level adjustments. The only minor problem with the unit is that it takes a fraction of a second to determine the source and clips a fraction of a second off the first part of a song from a CD or DVD. This is not a problem with a DVD once the movie starts. I can live with this little problem because the sound is so pure. The processor also sends L,C,R,LS,RS sound from a music CD to the proper amplifier or you can select stereo mode for just L & R channels. Music DTS CD's are awesome. The combination of this processor and the 9440A's create a sound that is all around me. Every channel is important. I have never heard such separation and blend at the same time. All of the VU meters work and look really cool but I removed the meter lamps because too much light leaks in to the theater. With the Altec speakers that I am using, I don't feel the need to alter the sound with an equalizer, tone control or effects. The sound is great unaltered. I am a happy customer. I am just a "poor boy" and feel that if someone would recreate the 9440A's that I would not be able to afford the new amplifier. Even a used 9440A including the purchase price, parts and the time to get them in working state is not cheap. My amplifiers are mounted in a relay rack just outside of my home theater. There is some mechanical hum from the power transformers in the 4 amplifiers but in the theater with even low level source material the mechanical hum is inaudible. The hum out of the speakers is 99% gone. I have been learning as I go and I know that I can get rid of the last 1% of the hum by moving the signal cables inside the amplifiers. I know this because I got all of the hum out of my surrounds by moving the cables from the input jacks inside the amplifier. It is a rascal to pull the amplifiers out of the rack to do anything inside the amplifier. My wife has been very patient with amplifiers and amplifier parts everywhere (dining room, kitchen, garage, bedroom and halls in the house) I am taking a little break but someday I will work on getting rid of the last 1% of the hum. I just watched "The River Wild" on this system. I love white water rafting and the sounds are so realistic.