Isn't your TIME worth more than the advantage of a lower cost IC? The reason many manufacturers use low cost (and consequently low performance) IC's is because the accumulated cost over 1000's of units gets expensive, and a difference in price of even $1 can be a lot of extra profit for the middle management, etc. This is why I am asked to do custom designs that use the BEST that we can do, rather than just what will meet measurement spec. This includes the 5534, that was, when it was first introduced, was a pretty well performing IC, BUT that does not make it as good as a well done discrete design. Now, how do I know? Well, I did an A-B test decades ago, where I directly compared (as closely as possible) a discrete op amp against a 5534. I really wanted the 5534 to succeed! It gets really boring to have to build my own op amps. Yes, IF I could have the ideal IC, I would use it just about everywhere. It just has not happened that I have ever found one (at any price) much less the 5534, that did it completely right.
Now, I realize that is recently fashionable to believe that everything (that measures well) sounds as good as anything else, and I cannot help those who believe that, but I (and the hi end audio public) still find that discrete is better than IC based designs, at any engineering level.
Now, I realize that is recently fashionable to believe that everything (that measures well) sounds as good as anything else, and I cannot help those who believe that, but I (and the hi end audio public) still find that discrete is better than IC based designs, at any engineering level.
Note pls I said very good. Not perfected. The weak link today is the source material.... CD are vastly inferior to the master recorded source material. The closest a consumer has to better /best source material is the HD download. Loudspeakers still are in the running for the weakest link but they have improved tremendously since CD and LP were invented that finding superior source material (technically) that is not compressed, and crunched and limited in resolution and low distortion is showing now.
an analogy --- I thought when i saw HD DVD that was the best. How could it be better than this. But then I saw UHD and it is visibly better.
As good as the audio has been.... the LP has a lot of unwanted noise (W&F, rumble and surface noise, to mention a few of the sub audio freqs generated) that they are like VHS video of the audio world. They can be made to broadcast standards and kept in tune and looks good. CD got rid of a lot of the LP artifact/junk and didnt need to have the LP cutter electronics cut lows at 60-80Hz and other issues. Just made things sound better. But not perfected yet. not enough bits to be inaudible.... However, at 24bits and high sampling rates.... it is like the UHD. Its better and thank the Gods we have computer technology converging to allow down loads of these Hi-Res Audio sources.
Technically, it just keeps getting better... with some setbacks but eventually making progress forward.
THx-RNMarsh
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Hmmm ... I find "vastly inferior" to be a bit strong - I've done some experiments with HD material, by downsampling to CD "quality", and subtracting that from the "superior" rendition - all that's there in the difference are tiny snippets of transient, blow, type of sounds; eg. the scraping of a chair on the floor ... there was very little in it I would call of "musical" significance.
Where the differences are, I find, is in the quality of the playback mechanism - if optimised to get the best from HD material, well, then the latter does sound quite superior ...
Where the differences are, I find, is in the quality of the playback mechanism - if optimised to get the best from HD material, well, then the latter does sound quite superior ...
IMO it is vastly inferior. My components and systems are not optimised for a particular format. They are technically excellent as a system and the source material quality shows thru easily. You have to make your own recordings with very good recording and playback equipment.... then compare that to LP or CD and HD. If you still dont think so, then so be it. Fortunately, the audio, video and the rest of electronics world is still revolving (and evolving). For myself, video has got a lot better. And audio has got better, over-all. It continues that way IMO. [minus MP3, and tape cassettes, of course. Not everything was a plus getting to this point]
For those who still get great pleasure from their records (LP), I would suggest a low cut filter of 'proper' design to reduce distortion thru the system and speakers. Maybe a new thread on circuitry to do this 'properly' would be nice for LP fans.
THx-RNMarsh
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Richard, my approach is to use source material to tell me how good the system is; not, relying on the system telling me how good the source material is - and I do this because it is extremely effective in raising the standard of playback. IME, technical excellence means very little, because the measuring of the "excellence" doesn't include everything that counts, at the moment.
Making excellent recordings is not the point - we have to, want to deal with all the wonderful performances that have been captured in the past, and make the best of them, IMO. My analogy is having a car, for which you build "perfect" roads - the bigger reality is that many roads are pretty hairy, and the technically excellent car is the one that handles those situations with aplomb, and doesn't constantly signal to the driver that it's making a meal of the journey - it's the relaxed enjoying of the travelling that's key ...
Making excellent recordings is not the point - we have to, want to deal with all the wonderful performances that have been captured in the past, and make the best of them, IMO. My analogy is having a car, for which you build "perfect" roads - the bigger reality is that many roads are pretty hairy, and the technically excellent car is the one that handles those situations with aplomb, and doesn't constantly signal to the driver that it's making a meal of the journey - it's the relaxed enjoying of the travelling that's key ...
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Yes, Richard, I for one would like to see your idea of a proper low cut filter. I think that it is needed for LP play back. No use passing low frequency garbage that is not music. What would be a good -3db point?
Thx
If you do use an HP filter on LP playback, you are really looking to reduce 3 things
1. Arm resonances in the 6-10 Hz region
2. Record warp in the 0.5 to 1 Hz region (should only be an issue in DC coupled systems and if the warp is really bad)
3. Bearing/platter rumble - again really only a issue in lesser systems
DS discusses this in his SSAD book. Seems a - 3dB of around 15 Hz with s roll off of 40 dB/decade is about right, all compromises considered. Of course, should be able to be switched in or out.
1. Arm resonances in the 6-10 Hz region
2. Record warp in the 0.5 to 1 Hz region (should only be an issue in DC coupled systems and if the warp is really bad)
3. Bearing/platter rumble - again really only a issue in lesser systems
DS discusses this in his SSAD book. Seems a - 3dB of around 15 Hz with s roll off of 40 dB/decade is about right, all compromises considered. Of course, should be able to be switched in or out.
Here's Rod Elliot's classic Subsonic (much steeper at 36dB/octave, 17Hz vs 12db/octave [40db/dec] ):
Subsonic / Rumble Filter for Phono preamps and Sub-Woofers
And of course, our own monty's very cool:
http://www.diyaudio.com/forums/anal...ore-effective-than-just-high-pass-filter.html
"Firstly, virtually no discs have any real stereo separation below about 200Hz or so at most, this means that I can lose the separation at, say, 150Hz without any change to the original audio. By splitting the channels at this frequency with 40dB/Decade filters and then mixing the two low frequency tracks together the rumble can be almost completely eliminated with far greater effectivity than just using a high pass filter. It will cancel rumble of far far higher frequencies than just a high pass filter ever could. No more 'road noise' !
Secondly, after this has been applied, the remaining rumble is of very low frequency, and a simple 40dB/decade filter at 12Hz does the job wonderfully. After this has been applied, the rumble becomes invisible on the waveform (and more importantly inaudible), as opposed to simply having the subsonic elements attenuated when using a high pass filter. This filter really works wonders at reducing low frequency surface noise well above 100Hz.
I have incorporated my findings into a circuit that will sit between my phono preamp and control amp (see attached) although a little more complicated than a steep subsonic filter, the extra complexity is well worth it. The circuit applies an 60dB/Decade filter at 12Hz, and collapses the stereo image below 160Hz. When using these filters on Audacity the rumble is reduced by about 24dB at 20Hz."
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And then monty's even more complex circuit at:
http://www.diyaudio.com/forums/anal...than-just-high-pass-filter-3.html#post3573990
"Here's the new topology, haven't got round to working out values yet ...
It's basically based around three basic subsystems...
1. The mid to side converter. This turns Right and Left to R+L and R-L (or mid and side). Filter bypass options by a 3 way 4 pole rotary switch for stereo (Lbp and Rbp), and mono (Mbp).
2. Filters. A 36dB Butterworth filter tuned to about 15Hz for the R+L channel, as most of the lateral rumble is below audio frequency. A 12dB bessel filter tuned to about 150Hz for the R-L channel - the low group delay of the Bessel filter ensures that the frequency response won't be too bumpy . Also a stereo collapse option via the Mono/Stereo switch.
3. Mid Side to Right and Left. Takes the filtered R+L (R+L f) and R-L (R-L f) and converts to Right and Left outputs using a summing amp and a difference amp.
It's a little more complex than the first circuit at 10 opamps, I included the buffer into the Bessel filter to keep things even so it can be done with a quad for the first stage, a quad for the second stage, and a dual for the last stage. The buffer is also included because toggle switches are usually MBB and I don't want to ground any opamp outputs or present an output impedance to the input of the Bessel."
http://www.diyaudio.com/forums/anal...than-just-high-pass-filter-3.html#post3573990
"Here's the new topology, haven't got round to working out values yet ...
It's basically based around three basic subsystems...
1. The mid to side converter. This turns Right and Left to R+L and R-L (or mid and side). Filter bypass options by a 3 way 4 pole rotary switch for stereo (Lbp and Rbp), and mono (Mbp).
2. Filters. A 36dB Butterworth filter tuned to about 15Hz for the R+L channel, as most of the lateral rumble is below audio frequency. A 12dB bessel filter tuned to about 150Hz for the R-L channel - the low group delay of the Bessel filter ensures that the frequency response won't be too bumpy . Also a stereo collapse option via the Mono/Stereo switch.
3. Mid Side to Right and Left. Takes the filtered R+L (R+L f) and R-L (R-L f) and converts to Right and Left outputs using a summing amp and a difference amp.
It's a little more complex than the first circuit at 10 opamps, I included the buffer into the Bessel filter to keep things even so it can be done with a quad for the first stage, a quad for the second stage, and a dual for the last stage. The buffer is also included because toggle switches are usually MBB and I don't want to ground any opamp outputs or present an output impedance to the input of the Bessel."
2. Filters. A 36dB Butterworth filter tuned to about 15Hz for the R+L channel, as most of the lateral rumble is below audio frequency. A 12dB bessel filter tuned to about 150Hz for the R-L channel - the low group delay of the Bessel filter ensures that the frequency response won't be too bumpy . Also a stereo collapse option via the Mono/Stereo switch.
[/I]"
This is important. Low Group delay maintains the clarity and tonal accuracy of the bass instruments. Glad that it was discussed and worked on by others who know what needs to be done for a better LP based sound system.
However, the 1/f noise in non-LP based systems need a similar cut-off design for sensitive circuits.
How would one design such a filter into existing preamp or system designs.... rather than a lot of extra/additional external circuitry?
THx-RNMarsh
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With regard to peeking, if one's hearing is so "poor" that one has to resort to DBT procedures to be confident that there is an audible difference, then I don't know why they bother with "hifi" - surely any old bit of rubbish will do the trick ...
Because as been said many times your hearing can be fooled, it is the scientific way.
This is the sort of chant those that could see the emperors new cloths always repeat, the only ones being fooled are these (probably yourself included).
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