Home Vintage Asylum

Classic gear from yesteryear; vintage audio standing the test of time.

[ Follow Ups ] Thread: [ Display  All  Email ] [ Vintage Asylum ]
[ Alert Moderator ]

Re: VINTAGE STUPID - why not new

Read your post with some interest. I'm about 3 years older than you, and still enjoy tinkering. I've pretty much tried everything over the years. So, naturally, I have a few comments.

I currently am using and NAD C350 integrated amp. A remarkably good sounding piece of gear for the $325 I paid for it. The preamp is electrically separate, having it's own power transformer and power supply. The case is light gauge steel, with a molded plastic front panel. It looks cheap. And that bothers me. Yet, I have not found anything I like better. It dawned on me that if it had a heavy gauge steel case, and a milled aluminum front panel about 10 mm thick, it could be sold for $2500 as a "high end" product and the audiophiles would think it was a bargain. I even found myself thinking about doing that. Such is the pressure we put on ourselves for exclusivity, appearances, and just plain old hype.

More recently, I picked up a clean Dyna PAT-4 preamp in nice shape. These things were never known for great sound. But mine measured well through the line level stages. So I decided to run some simple tests, hooking it up though the tape monitor circuit of my NAD and using the level control to match the level to unity gain. Then when I switched the tape monitor circuit in or out there was no level change, and any change I did hear would be coloration introduced by the PAT-4. Bottom line? There was no difference I could hear with the PAT-4 in or out. It was completely neutral. I did not evaluate the phono stage. Inserting the NAD preamp into the PAT-4 tape circuit was equally neutral.

So I have two preamps that model the proverbial "straight wire with gain" in their line stages. (a number of other preamps or preamp sections of integrated amps or receivers have not passed this test, they have all added coloration of some sort). Why would I want to replace them? Cosmetics or the elitism of name brand recognition are the only reasons I can think of for line stages. True, I did not evaluate the phono section, and my test method won't work for phono amps. The NAD has none, and I did not check out the Dyna. So I guess if I needed a phono section or was unhappy with the one I had, this test would be worthless. But NAD makes a fine outboard phono amp for $139 as do many other companies, and if I needed a phono section, I would probably go that route.

I haven't done it recently, but some years ago I measured the RIAA equalization on a number of phono preamps. I was rather surprised just how many were off spec. by significant amounts, often differing in the left and right channels. Since this translates into frequency response variations, it's small wonder that many phono amps sounded different. As an experiment, I padded two different preamps that sounded quite different (and measured differently)to bring their RIAA curves to within +/- 0.2 dB. After that the two preamps sounded nearly identical, but only after the input impedances were corrected to the 47,000 ohm standard, and the input capacitance was equalized in both to the same value. So the circuit design itself was of little importance once the frequency response was made the same in both designs.

One more point. Floyd Toole of Harman International has run some tests showing that very low Q resonances of low amplitude are surprisingly audible. This same finding also applies to electronics in terms of frequency response variations. If you have ever played with the "tilt" control on a Luxman preamp, you'll know just how sensitive to small tilts the ear is. So, if a preamp (or other component) has a spec of 20-20k Hz +/-0.5 dB, and one is ruler flat through the range, and rolls off at the extremes, it will sound quite different than one which meets the same specs but is tilted downward over the whole range, being + 0.5 dB at 20 Hz and -0.5dB at 20 kHz. The folks who design equipment know about this and do take advantage of it. (for example, I had an Arcam CD player which was up 0.5 dB at 1 kHz in a broad rise, and was at -0.5 at the extremes. The result was higher midrange output and a forward sound compared to most other CD players.) Was that deliberate? I think it was. On first hearing it made the Arcam much clearer and more detailed sounding. Then there was the Mark Levinson power amp that met the same +/- 0.5 dB spec., but which was at reference level at 20, 1 kHz, and 20 kHz; and was +0.5 dB at 300 Hz and -0.5 dB at 3 kHz. Amps don't behave that way. Clearly, it was tweaked to have that contour and to have a distinctive and pleasing sound.

The hype is that advances in circuit design, premium components, etc. make the product sound "better". The reality is very often that it is not because of the wonderfullness of the circuit design, but because of deliberate tinkering with frequency response or other properties. You can do that with an equalizer, if that's what you want.

Bottom line, I really don't see much evidence of significant advances in circuit designs or construction techniques in electroncs. The better vintage gear, in good condition and checked for frequency response should be able to hold it's own against the latest and greatest. There is a caveat! Bench testing of frequency response is of no value if there are impedance mismatches at the inputs or outputs. I have found quite a number of mismatches that color the sound. So in the end, it's not so much component quality that counts, but the matching and interfacing of the components that counts. You still have to try it and see for yourself how it sounds in your system.

Jerry

This post is made possible by the generous support of people like you and our sponsors:
  Crux Audio  

Follow Ups Full Thread
Follow Ups
You can not post to an archived thread.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]