pmr@drutx.UUCP (09/19/84)
<?> (Re: What type of equipment does Phil R. have?, part 6.) For some of you, it may be disappointing to find out that I don't own a fine Conrad Johnson, Audio Research, Spectral, Electron Kinetics, Krell, or Levinson after hearing me praise their sonic virtues for so long. My views toward high- end gear have not changed and all of these manufacturers make excellent equipment. I still praise some of equipment in this category as being state-of- the-art in construction and in sonic accuracy and recommend it to those who can afford it. Part of what these manufacturers do differently from mid-fi manufacturers is to pay excruciating attention to detail and use better quality components, both of which cost much more to implement. Most equipment with sound circuit topologies can be easily modified to alter their transfer functions and corresponding sonic accuracy, just as high-end manufacturers do. Carver, Musical Concepts, et. al., have already proved this approach with the Carver t-mods, Musical Concepts super mods, and the like to existing production amplifiers and receivers. It's taken me many years of research and experimentation, many months behind a calculator and in consultation, and many weeks with a soldering iron to achieve the level of sonic accuracy that my equipment has today. There are roughly three classes of mods I've made over standard production systems. These classes are: - those generally recognized as good ideas like decent cables and connectors. The cable mods can be performed by anyone and the connectors by those with a little skill and a soldering iron. - those that get labeled as golden-ear ideas because they're less than universally accepted, such as Litz wire in various places in the system. Disregarding the debate on this issue, these mods appear to be simple on the surface. But, for example, when reducing the supply impedance with larger wires and capacitors, parasitic oscillations can result (especially in preamps) and instead of improving the sound of the system, it gets MUCH worse. Anyone with soldering iron skill can perform these mods but perform them in a logical manner and in small steps rather than one fail swoop. - those that may or may not be generally accepted as good ideas, but should be pointed out as "not for the rank amateur". These mods include those that alter the mass or suspension characteristics of a turntable/tonearm/cartridge, or change the basic circuit topology. It's possible for someone to stumble around and move a resonance in a turntable/tonearm into the audible spectrum (or some other similar fumble) and degrade/destroy an amplifier/turntable, or even inflict personal injury. Don't attempt these types of mods if you don't completely understand what's going on. I was also going to write a paragraph on how my equipment sounded as compared to other gear in its class. This description quickly became very subjective and incredibly involved so I decided against including it. Suffice it to say that both the preamp and the power amp no longer resemble the original schematics, and that they both sound good enough to be classified in the lower part of the high-end category, whatever that means. Remember that the same patience and care have gone into modifying this equipment as in designing the listening room. Enough of this, on with the show! Preamp: The preamp is a 4-year old highly modified Technics SU-8055 integrated amp, preamp section used only. Phono preamp section is class A with about 35dB of gain, second gain stage is an op amp with about 20dB of gain. Some of the mods: mylar and polystyrene capacitors, hand-matched components in the RIAA network, hand-made #16 internal Litz wiring made from #30 OFHC wire-wrap wire, new regulators, gold RCA jacks, single point ground configuration, etc. (I kept the knobs! :-) Amplifier: The power amplifier is a 10-year old highly modified McIntosh 2100. All circuitry is differential class AB using bipolar devices and autoformer-coupled output, 136 WRMS/ch at clipping, both channels driven. Some of the mods: 0.3 Farads in the main power supply, new input and driver bias circuits, mylar and polystyrene capacitors, hand-made #10 internal Litz wiring made from #26 OFHC wire-wrap wire, true single-point grounding arrangement, gold RCA jacks, low-level circuitry regulators, etc. Welp, there you have it. A few other things that you may be interrested in are that my hearing ability extends to 17KHz in my right ear and 18.5KHz in my left. I spend a lot of my free time reading both objective (JAES type) and subjective (TAS type) articles about fidelity and listening to both live and recorded music. I spend a lot of time in audio salons listening to mostly high-end gear and recording studios listening to the latest efforts and discussing techniques. (Yes, I even listen to their digitally-mastered tapes :-). I (try to) play acoustic guitar, piano, and electric bass. I attend jazz and classical concerts on a regular basis (season ticket holder sitting next to T. Buckley fourth row, dead center). ------------------ Some of the interresting questions received by email about this series: Someone asked me about how I control the vent noise from the heating system. The answer is central hot water (not steam) heating. The only noise this system makes is a gentle creaking of the heater elements as they warm up (~18dB) and the electronic pilot light starting in the utility room (~30dB). Someone else asked me how long it took for the room and stereo to evolve to its present level. It's taken a long time. The room took about four years and thirty or forty revisions until I settled on its present configuration. The loudspeakers were originally started 13 years ago and have been continuously refined in one way or another, mostly from improved materials and components. The amplifier and preamp have also been undergoing one modification or another for the last five years. I plan to alter the crossover network once again this winter and reroute some of the amplifier's internal wiring. Still another person asked me why I modify things instead of buying new equipment. Well, I love to tinker. (My wife thinks that I should join Disassemblers Anonymous :-) I also enjoy trying to hear differences in the transfer function after performing a modification. This approach has taught me a lot about subjective evaluations, projecting expectations, and a lot about being a good listener. The next major purchase for this system is a new phono cartridge (Talisman S, Monster Alpha 1, or something like that). ------------------ I hope you enjoyed reading this series as much as I did writing it. I didn't realize how much work I've put into this system until I started explaining it. I'd encourage anyone to try modifying their own system if they are so inclined. If you will not/cannot for whatever reason, buy high-end instead. If you're truly into listening, it's worth it! (I have the phone number for DA if you get hooked :-) Yours for higher fidelity, Phil Rastocny AT&T-ISL ihnp4!drufl!pmr