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Posts: 295
Location: Atlanta
Joined: May 9, 2005
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Well, yeah, I know. I meant the message as an experiment to see if what the poster was hearing was a polarity problem, or problems caused by auto-tune or just plain bad singing. I hope noone thought I was suggesting that as a permanent solution. Now, that said I find that almost every recording I have on CD is inverted, BUT, it's not because of the recording, it's because of the CD player itself. Most commercially available CD players invert. I would imagine the impression that out of all available recordings, you ave a 50/50 chance of hearing one inverted comes from guys who switch back-and-forth from their CD player to their turntable often. Think about it, how many people have one of each of their albums in both formats? I would imagine not very many. Given that most CD players invert, and most turntables don't, people would get the impression that the recordings are the problem. I would imagine this is also a big reason a lot of people prefer vinyl. Once you hear a piece you are familiar with in the correct polarity, the difference is night and day, THD and frequency response numbers be damned. So, switching speaker wires is in no way a solution, but a quick and easy way to see if that is in fact the problem. Now, for solutions: If all you listen to is CDs, you can probably be very happy living with the speaker cables inverted. (free solution) If you listen to a mix of CD/vinyl, you may have an almost as easy solution, if you have access to the tonearm wires at the back of the cartridge. Leave the speaker cables inverted, that's the easiest way to fix CD polarity. On the back of the phono cartridge, switch the red wire with the green wire, and the white wire with the blue one. Since the phono cartridge is a truly balanced signal, this succesfully inverts the phono signal as well. Now, almost all of your recordings will play correct polarity. Sorry guys that have P-mount cartridges, it's doable, but not quite as easy. I don't know many preamps that have polarity switches off the top of my head, but most likely the preamp would have to have balanced circuitry to make it work, so try looking around for balanced in/out preamps. I tried incorporating a polarity invert switch into my preamp design, which is simple, and single-ended. The only way it can work is if you are feeding the outputs into monoblocks. I'm sure there are probably ways to do it in a single-ended topology, but I believe in the "as simple as possible" school of thought (which probably comes directly from my work as a repair tech! :) ). I do have one commercial preamp I own that does have a polarity switch, a Parasound P/HD-1500. It is a dual-mono layout with balanced circuitry, very good build quality, and made with premium parts (I think half the weight of the thing is Black Gate caps), and designed by John Curl. Unfortunately, they do not seem to be easy to find, and not well known. On the other hand, that does seem to be a buyer's advantage, because once you locate one, it is normally priced FAR below its worth to someone who loves music. BT p.s., John Curl, if you happen to read this, I was curious as to why the P/HD-1500 didn't have a few vents on top of the case? When I'm using mine, I tend to run it "topless" in the rack. Should the mosfets not be allowed to cool too much? TIA
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