mark@motcsd.UUCP (Mark Jeghers) (05/31/89)
I have some Compact Discs with *enourmous* dynamic range in their recordings (quiet parts are REAL quiet, loud parts are REAL loud) - primarily my classical stuff. I have to constantly change the volume or else blast my family out... I'm thinking of building a limiter to even out the overall volume of such albums. I think that the compressor section of a Signetics NE560 Compandor would be just right. Also, I believe that setting it up as a *compressor* is more preferable than setting it up as an *auto-level-control*. I would like to make the compressor variable-slope, so as to adjust the degree of the compression. Any ideas? Suggestions? Am I on the right track? -- Mark Jeghers "I'm the King of Eight and I'm here to state Motorola Computer Systems that everything here has to total eight! ....uunet!apple!motcsd!greek!mark The gaurds, for instance, at my gate ...hplabs!hpda!/ must always total exactly eight!"
honig@ics.uci.edu (David A. Honig) (05/31/89)
Don't build a limiter for your CD player, go buy a turntable and some records. :-) -- David A Honig
strong@tc.fluke.COM (Norm Strong) (06/01/89)
In article <376@greek.UUCP> mark@greek.UUCP (Mark Jeghers) writes: }I have some Compact Discs with *enourmous* dynamic range in their }recordings (quiet parts are REAL quiet, loud parts are REAL loud) - }primarily my classical stuff. I have to constantly change the volume or }else blast my family out... } }I'm thinking of building a limiter to even out the overall volume of }such albums. I think that the compressor section of a Signetics NE560 }Compandor would be just right. Also, I believe that setting it up as a }*compressor* is more preferable than setting it up as an }*auto-level-control*. I would like to make the compressor }variable-slope, so as to adjust the degree of the compression. } Do you have a HI-Fi VCR with automatic level control? If so, feed the signal at high level into the VCR; the signal out of the VCR is compressed and can be used to feed your amplifier. -- Norm (strong@tc.fluke.com)
collinge@uvicctr.UVic.ca.UUCP (Doug Collinge) (06/01/89)
In article <376@greek.UUCP> mark@greek.UUCP (Mark Jeghers) writes: >I have some Compact Discs with *enourmous* dynamic range ... > >I'm thinking of building a limiter ... Ha, ha, ha! I find this very funny. The recording companies will soon discover that very few people actually want dynamic range - when you just have that Beethoven string quartet on as quiet dinner music you can't even hear the quiet parts. Likewise, in your car, you can't hear anything at all unless it is all uniformly at the threshold of pain. So before too long you'll find all CD's sounding exactly like cassette tapes. Cheers... -- Doug Collinge School of Music, University of Victoria, PO Box 1700, Victoria, B.C., Canada, V8W 2Y2 collinge@uvunix.BITNET decvax!uw-beaver!uvicctr!collinge ubc-vision!uvicctr!collinge __... ...__ _.. . ..._ . __... __. _. .._ ..._._
usenet@cps3xx.UUCP (Usenet file owner) (06/01/89)
If you are planning on using the Signetics chip, might I suggest that instead of simply using the peak input voltage to control the gain cell, you might look into using a real RMS detector chip as in the dBX noise reduction scheme. This setup would be a bit more tricky to design, but would be superior to simply using the peak voltage-- your gain tracking would be more accurate. I believe that NEC makes just such an item, intended to be used in a dBX type NR setup. I think that you might find this chip in the "Linear Circuits for Audio System" (sic) databook. I have no idea as to the availability of this device. Call a distributor and ask for a sample... As for your actual compression range, I imagine that you would be looking at a maximium ratio of 2:1 or so. Any more would begin to sound really funky. As with any compressor, noise pumping might become a problem--although with CD source material, this will most likely be kept to a minimum.
strong@tc.fluke.COM (Norm Strong) (06/02/89)
In article <679@uvicctr.UVic.ca.UUCP> collinge@uvicctr.UVic.ca.UUCP (Doug Collinge) writes: }In article <376@greek.UUCP> mark@greek.UUCP (Mark Jeghers) writes: }>I have some Compact Discs with *enourmous* dynamic range ... }> }>I'm thinking of building a limiter ... } }Ha, ha, ha! I find this very funny. The recording companies will soon }discover that very few people actually want dynamic range - when you just }have that Beethoven string quartet on as quiet dinner music you can't even }hear the quiet parts. Likewise, in your car, you can't hear anything at }all unless it is all uniformly at the threshold of pain. So before too }long you'll find all CD's sounding exactly like cassette tapes. I discovered an interesting way to obtain "non-intrusive" music from my CDs. I dub a 6 hour program of music to eat dinner by (or such other activities as warrant) on a Hi-Fi VCR using the automatic level control position. By feeding the VCR a signal much higher than it needs, the end product is music compressed to about 40db dynamic range. I now have 6 hours of continuous music with fairly shallow dynamics--perfect for background. And you don't need a CD changer. Another solution, if you don't have a Hi-Fi VCR, is to record music from a classical FM station. The station already compresses the signal in order to increase their area of coverage. I would guess a practical maximum of about 50db from this source. -- Norm (strong@tc.fluke.com)
irv@happym.wa.com (Irving Wolfe) (06/04/89)
It's absolutely a fact. We don't want dynamic range most of the time. It IS
real harmful (not just useless) in background music and car music, and that's
most of my listening and probably the same is true for others.
If and when I can buy another CD player, you can be darned sure it will be a
model that has adjustable dynamic range (built in variable compression) so I
can have a real concert when I want one, but can have a pleasant experience
the rest of the time too.
--
Irving Wolfe irv@happym.wa.com Happy Man Corp, 119 Aloha St
206/282-9598 tikal!camco!happym!irv Seattle, WA 98109-3799
SOLID VALUE, the investment letter for Benj. Graham's intelligent investors
(free sample on request (include street address): tami@happym.wa.com)jeffw@midas.STS.TEK.COM (Jeff Winslow) (06/04/89)
>It's absolutely a fact. We don't want dynamic range most of the time. It IS >real harmful (not just useless) in background music and car music, and that's >most of my listening and probably the same is true for others. The real answer is evading you all. Music is not a decoration, like wallpaper. Background music is a tool of the Devil. Music in the car is a travesty. Music is to be Listened to! Those who show disrespect will have their ears perforated by the dynamic range of The New Reproducers. only half :-) Jeff Winslow
bergman@m2c.m2c.org (Michael Bergman) (06/05/89)
To overcome this same problem, a friend of mine took one of the inexpensive dbx units from DAK, and fiddled the wiring so that he had the option of listening to the compressed signal from an uncompressed source. He did this to overcome the high background noise level of his wife's loom (she is a free-lance weaver). When she isn't weaving, a push of the button and full dynamic range is once again theirs to enjoy. -- --mike bergman (w) 75 North Drive, Westborough, MA 01581, USA +1 (508) 870-0312 UUCP: harvard!m2c!bergman INTERNET: bergman@m2c.org
strong@tc.fluke.COM (Norm Strong) (06/06/89)
In article <788@happym.wa.com> irv@happym.UUCP (0000-Irving Wolfe) writes: }It's absolutely a fact. We don't want dynamic range most of the time. It IS }real harmful (not just useless) in background music and car music, and that's }most of my listening and probably the same is true for others. } }If and when I can buy another CD player, you can be darned sure it will be a }model that has adjustable dynamic range (built in variable compression) so I }can have a real concert when I want one, but can have a pleasant experience }the rest of the time too. This question come up frequently. I know of 5 ways to solve this problem: 1. Manually ride the gain control while making your copy. This is the best way, but it requires that you familiarize yourself with the music beforehand. You'll probably need a practice run or two. 2. Buy a professional compander. These sell for at least $500, which generally sinks that idea. 3. Buy a dbx CD player. dbx puts a compander in each of their CD players for just the purpose we're talking about. I know of no other consumer CD player with this feature. 4. Make all your tapes off the FM radio. All FM signals are severely compressed in order to increase the area of signal coverage. (Yuk!) control. This is the method I use. If your CD player has a volume control, turn it up to maximum before making the copy. The VCR will cut the dynamic range by at least 20, probably 40db, and it will sound just fine in your car. The AGC circuit will probably be "blinded" from time to time by tympani and trombones, but nothing's perfect. -- Norm (strong@tc.fluke.com)
bruce@nmsu.edu (Bruce Rowen) (06/07/89)
I agree that wide dynamics can be a pain sometimes. I have the dbx DX5 CD player with the compression circuitry and find this the greatest thing since sliced bread. I use it extensively for background music or car tapes. A friend of mine would like to get the same player for similar purposes, however this model can't be found any more. The only other CD player with a "compander" that I am aware of is a unit made by Sound Craftsman that sells for about $450 mail order. -Bruce -- -Bruce
collinge@uvicctr.UVic.ca.UUCP (Doug Collinge) (06/07/89)
>The real answer is evading you all. Music is not a decoration, like wallpaper. >Background music is a tool of the Devil. Music in the car is a travesty. As a musician and composer I have to second this sentiment. I deplore the attitude that music is some kind of pleasant substance to be paid for by the hour. But I guess I have an axe to grind... -- Doug Collinge School of Music, University of Victoria, PO Box 1700, Victoria, B.C., Canada, V8W 2Y2 collinge@uvunix.BITNET decvax!uw-beaver!uvicctr!collinge ubc-vision!uvicctr!collinge __... ...__ _.. . ..._ . __... __. _. .._ ..._._
tcb1@tank.uchicago.edu (tom charles braden) (06/07/89)
In article <4494@midas.STS.TEK.COM> jeffw@midas.STS.TEK.COM (Jeff Winslow) writes: >Music is not a decoration, like wallpaper. >Background music is a tool of the Devil. Music in the car is a travesty. >Music is to be Listened to! > only half :-) I'll respond to the half that wasn't smiling... I fail to understand this idea that music (or any art form) is so delicate that it must be protected from the rest of life. Should we remove anything faintly artistic from our walls and lock it up in a museum, to be viewed only when the moon is full? A composer has the right to compose a piece to be heard only at night, or only in a completely empty room, but I feel sympathetic towards artisans who feel the need to make even simple things like ashtrays and rugs things of beauty, or musicians of all sorts for whom music forms a part of a social occasion. There's not enough beauty in the world without specifying that all beauty must be totally useless. <rant off> -- -------------------------------------------------------------------------- Tom Braden ! c/o WHPK ! "The few thoughts left to me University ! 5706 S University ! I shepherd so lovingly" of Chicago ! Chicago, IL 60637 ! - David Thomas
henry@utzoo.uucp (Henry Spencer) (06/08/89)
In article <4494@midas.STS.TEK.COM> jeffw@midas.STS.TEK.COM (Jeff Winslow) writes: >Music is not a decoration, like wallpaper. >Background music is a tool of the Devil... Do remember that a substantial fraction of classical music was specifically composed to be background music. -- You *can* understand sendmail, | Henry Spencer at U of Toronto Zoology but it's not worth it. -Collyer| uunet!attcan!utzoo!henry henry@zoo.toronto.edu
al@qiclab.UUCP (Al Peterman) (06/08/89)
In article <BRUCE.89Jun6112123@sparta.nmsu.edu> bruce@nmsu.edu (Bruce Rowen) writes: >I agree that wide dynamics can be a pain sometimes. I have the dbx DX5 >CD player with the compression circuitry and find this the greatest >thing since sliced bread. I use it extensively for background music or >car tapes. A friend of mine would like to get the same player for >similar purposes, however this model can't be found any more. The >only other CD player with a "compander" that I am aware of is a unit >made by Sound Craftsman that sells for about $450 mail order. Find a used DBX 117, 118 or 119. These companders will compre very nicely and make great car tapes. They can be found for $25 to $100 used in good condition. They have variable compression ratios so you can choose the amount of compression you need. You could use the DBX 128 which has the features of a 119 and a 122 combined, but you probably don't need the fixed 2:1 compression of the noise reduction section, and these often go for $100-150 (although a friend just got one for $25). Most of the other DBX clones (RG Dynamics, Pioneer etc.) do not compress, just expand and are therefore worthless in creating car tapes. -- Alan L. Peterman (503)-684-1984 hm Airborne N33291 Cessna Cardinal RG Net !tektronix!(psu-cs,reed)!qiclab!al
usenet@cps3xx.UUCP (Usenet file owner) (06/09/89)
It seems to me that simply lifting the applications circuit from the Signetics Linear databook. Their applications engineers put together a dandy little note called "compandor cookbook" Read it-live it-love it... >It is what you want< Or is it that Motorola bans it's employees from reading other companies data books :-)
mark@motcsd.UUCP (Mark Jeghers) (06/10/89)
In article <3350@cps3xx.UUCP> beyer@frith.UUCP (Don W Beyer) writes: > >Or is it that Motorola bans it's employees from reading other companies >data books :-) No, they only ban us from using Intel CPU's :-) -- Mark Jeghers "I'm the King of Eight and I'm here to state Motorola Computer Systems that everything here has to total eight! ....uunet!apple!motcsd!greek!mark The guards, for instance, at my gate ...hplabs!hpda!/ must always total exactly eight!"
jeffw@midas.STS.TEK.COM (Jeff Winslow) (06/10/89)
In article <1989Jun7.205326.6522@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes: >Do remember that a substantial fraction of classical music was specifically >composed to be background music. But - (no) surprise! - it's not near as interesting as that which wasn't. We now return you to your regularly scheduled programming... (followups directed to rec.music.classical - I tried to do it once before, let's see if it works this time.) Jeff Winslow
knudsen@ihlpl.ATT.COM (Knudsen) (06/10/89)
I was lucky enough to get one of those dbx DX-5m CD players with the built-in compressor. Variable, and very effective. It does take out some of the punch and kick of tympani and such, but there is another variable circuit provided to put the punch back in without losing the overall compression. All this is variable, and can be bypassed with a genuine relay. Overall the DX-5 is an excellent CD player. LAcks random play though. Costs $300 - $400. Yes, I bought this particular player just for the compression, for the reasons already cited. Given BSR/ADC/dbx's close working relationships with DAK, maybe DAK will be selling these players off for small change. Can't wait to read Drew Kaplan's purple prose ad -- this guy must have read thru all the Doc Smith "Lensmen" novels in Jr High school. Wow! -- Mike Knudsen Bell Labs(AT&T) att!ihlpl!knudsen knudsen@ihlpl.att.com Round and round the while() loop goes; "Whether it stops," Turing says, "no one knows!"
markz@ssc.UUCP (Mark Zenier) (06/11/89)
In article <3350@cps3xx.UUCP>, usenet@cps3xx.UUCP (Usenet file owner) writes: > > It seems to me that simply lifting the applications circuit from the > Signetics Linear databook. Their applications engineers put together > a dandy little note called "compandor cookbook" Read it-live it-love > it... >It is what you want< > > Or is it that Motorola bans it's employees from reading other companies > data books :-) Well, somebody in Motorola Semicondutor did an application note (APR2/D) on how to tap into the digital stream in a Sony CD player and implement a graphic equalizer digitally with a DSP56001. A couple of grand for development tools, and you could get one heck of a compander. :-) All in software. Mark Zenier uunet!nwnexus!pilchuck!ssc!markz markz@ssc.uucp uunet!amc!