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Old 28th August 2012, 03:22 PM   #551
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Quote:
Originally Posted by Bare View Post
All that circuitry? just to replace (poorly imo) a Stepped attenuator and a very few short wires.
Fill yer boots :-)
Except I don't quite see how that is going to:

1) Provide the gain for the MC and MM inputs

2) Perform the RIAA equalisation

3) Implement the balanced line inputs

4) Perform the balance and tone control functions

Do tell us how.
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Old 28th August 2012, 04:22 PM   #552
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DouglasSelf,
I am new to the DIY site and this is the first time I have seen one of your postings. I do have two of your books and I am studying them intently. It seems funny to me that so many find a tone control sacrilegious as they do so many other things to overcome this aversion. The room treatments, speaker placements, shelving and sloping of crossover networks to get the sound correct are all forms of tone control to me, just in another domain. I for one still think that there is nothing wrong with a proper tone control. If everything was absolutely perfect in the reproduction chain we would still have different rooms and the effects on frequency response. Thank you for all your knowledge and sharing it with the rest of the world.

Steven
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Old 28th August 2012, 05:51 PM   #553
redjr is offline redjr  United States
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Old 29th August 2012, 12:19 AM   #554
Pano is offline Pano  United States
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Quote:
Originally Posted by DouglasSelf View Post
1) Provide the gain for the MC and MM inputs
Use a ceramic cart. Nice high output. Forget the MM or MC. They're just gimmicks.
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2) Perform the RIAA equalisation
Not needed with the ceramic cart. (Or use a strain gauge)

Quote:
3) Implement the balanced line inputs
Use a transformer as a stepped attenuator.

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4) Perform the balance and tone control functions
Move the speakers back and forth. Use blankets or old quilts over them to change the tone.

See? Easy!
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Old 29th August 2012, 12:50 AM   #555
SY is offline SY  United States
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For balance, I usually have one of the servants stand in front of the louder channel's speaker.
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Old 29th August 2012, 12:57 AM   #556
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hmmmm...now I know why SY told me "Stand over there, please." at the last party.
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Old 29th August 2012, 01:01 AM   #557
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I have determined that no 1k stereo (dual gang) linear pots with a .5w power rating exist affordably in north america. omeg has no dealers that i can find, vishays at newark are only available from farnell for a $50 shipping charge. no one has the bournes pots in stock. alps doesn't make 1k. man oh man. i am frustrated!
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Old 29th August 2012, 03:06 PM   #558
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Originally Posted by owdeo View Post
......I'm posting here because I think the preamp I've built is subjectively "mildy strangling" the music. I find this interesting and was hoping to learn something by working out why. After all, this is a forum for DIY, not manufacturers, is it not? The recent spate of last minute comments implying that I have no basis for this opinion is pointless as everyone here must be aware of the debate over subjective vs objective and no matter which part of the spectrum you sit in no single person has all the answers. No one could prove that I can't hear what I'm hearing any more than I can prove that I can. The design must be audibly perfect as it measures so well. This is good science for anyone who uses an amplifier to display waveforms on a 'scope or generate impressive looking specs on paper, but for the rest of us who use them for enjoying music I think it's pretty questionable science...
Many high-end audio products are lauded for their carefully tailored harmonic distortion rather than the lack of it, so have you considered that you might be describing the effect of eliminating something from your audio chain that had been affecting the music programme? The clue to me is in your use of the term "strangled" which to me implies flat response and very low HF distortion. I've seen DestroyerX refer to it as "muffled" and there it infers no sweetening harmonics. Combined with intentionally flat response monitors, that could well add up to a purity of sound that perhaps you hadn't anticipated.

I think few of us us really want technically perfect reproduction, though it is the basic principle of high fidelity audio, which we somehow feel obliged to uphold, even though it doesn't mean we'll enjoy it most. On the other hand, if I wished to process the audio for broadcast, recording, relay, PA etc, I wouldn't hesitate to go for the most linear equipment available. You can get funky at the listening end any time without affecting other uses.
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Old 29th August 2012, 03:16 PM   #559
Mooly is offline Mooly  United Kingdom
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Originally Posted by Ian Finch View Post
I think few of us us really want technically perfect reproduction, though it is the basic principle of high fidelity audio, which we somehow feel obliged to uphold, even though it doesn't mean we'll enjoy it most. On the other hand, if I wished to process the audio for broadcast, recording, relay, PA etc, I wouldn't hesitate to go for the most linear equipment available. You can get funky at the listening end any time without affecting other uses.
Yes, yes, yes !!!!!!! finally a comment I 100% agree with and have said many many times myself.

What use is technical perfection when you don't actually like sitting and listening to it.
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Old 29th August 2012, 03:26 PM   #560
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Ian,
I find your answer to be an interesting read. Yes I think that most of us as manufacturers and designers are always thinking of making a device wherever it is in the chain as close to technically perfect as possible with no significant acoustic signature of its own. But your argument that perhaps we are missing something has a valid point also. I would say this goes to why some people are so enamored of vacuum tube equipment though most of this will just measure as an inferior reproducer. I am not saying that you can't go the extra mile and also have very technically correct design, but that is not what I am getting at. I think that it is the distortion of harmonics that those people find so attractive, minor changes to the reproduced sounds that make them feel that the sound is more natural or inviting. We think of instruments in music as being pure and simple creators of sounds but it is really all of the side bands that are making that sound, not just the pure tones that you can never recreate through a synthesizer. Why we like one guitar over another that are made by the same manufacturer from the same wood in the same manner. The subtle differences that we listen for. I assume that this is what Owdeo is missing, something that gives the sound character. Perhaps an increase in second harmonic distortion would make him happier, but how to do that in a controlled manner is not something I could answer.

Steven
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