That's it, AG is analog ground, DG digital ground, +A6V dc analog 6v. . . The kind of fork for the analog ground is an other sign for ground, maybe they mean different connection places, as the fork like is used for antenna too. But I think it's just a country/continent difference. "nelsonj_sce" <nelsonj_sce@...> wrote: > >Antdes, >I just wanted to compare some notes on the schems. I have not had a >chance to dig too deep yet but I want to see if you reached some of >the same conclusions I have on some of the notation... >1) Many connectors have both "AG" and "DG". Based on my quick look >this seems to mean Analog Ground (AG) and Digital Ground (DG). Do you >agree? In general something like "+A6" means "analog 6 Volts" > >2) It looks like the schems have a slightly different symbol for the >AG and DG. The AG ground looks like a horizontal line with three >vertical swipes under it where as the DG has a more traditional symbol >for ground. Do you agree? > >The first thing I want to try is to directly connect all of the AG and >DG cables to a single ground at the same place. By any chance, have >you tried that yet? > >Anyway, I think I have decoded the schems but I never hurts to compare >notes. Thanks. > > >--- In k5synth@yahoogroups.com, Antoine Desch\ufffdnes <antdes45@n...> wrote: >> Mine's not at -65 but at -47 dB with the TL072. >> >> nelsonj_sce@y... a \ufffdcrit: >> >> > >> > I got the schems yesterday and I will take a look at the ground >issue. >> > Although all grounds will eventually get to a single point, one idea >> > is to make sure the D and A get to the same ground at the same time - >> > that is make sure there is no path between the A and D grounds. >> > Anyway, I will try to look at the schems this weekend. >> > >> > I also just upgraded to OS1.2. I am a bit disappointed that the >> > Kfuenf editor still does not work for me. Oh well, more on that in my >> > next post. >> > >> > Also, I hooked up my J-station to the K5. The J-station has a very >> > good noise gate, as well as delay+reverb+chorus(ect). I have to crank >> > the noise gate up to about 65 to kill the line noise. But the K5 >> > sounds great through this unit and I recommend it if you happen to >> > have a J-station around. >> > --- In k5synth@yahoogroups.com, "antdes45dragonmaster" <antdes45@n...> >> > wrote: >> > > >> > > Buzzing in rear out is signal ground noise, all pcbs have sepparate >> > > analog grounds to PSU but linked together on the psu. >> > > >> > > --- In k5synth@yahoogroups.com, "nelsonj_sce" <nelsonj_sce@y...> >> > > wrote: >> > > > >> > > > Antdes, >> > > > Good information in the note below. It sounds like the good >news is >> > > > that the digital (D) and analog (A) have seperate grounds. From >> > > > everything I have been reading that is good news. If they had the >> > > > same ground on the same PCB we might be completely out of luck. >> > > Today >> > > > I ordered the latest OS ROM and schematics from Kawai so >hopefully, >> > > > once I have the schems, I make more informed suggestions on how to >> > > > reduce the ground noise. >> > > > >> > > > I did read something today that said that, although you should >have >> > > > separate A and D grounding, ultimately both the A and D should be >> > > > grounded at the same point. Otherwise, the D might inject >noise in >> > > to >> > > > the A ground. Based on your note, this might be just what is >going >> > > on >> > > > in the K5. >> > > > >> > > > Based on this observation, one thing to try would be to take the D >> > > > ground off of the power supply board and connect that ground >> > > directly >> > > > to the A ground on the transformer. We need to make sure the >power >> > > > supply board is still fully grounded even if we remove the D >ground, >> > > > but you should be able to check the schem and see if it looks like >> > > > this is an easy move. >> > > > >> > > > Anyway I don't want to do anything too fancy until I look at the >> > > > schems, but if it looks safe, this is the first thing I want to >> > > try. >> > > > (Or if you feel adventurous you could try it and tell me if it >> > > works!) >> > > > >> > > > Thanks for the note and let me know if you find anything else out. >> > > > >> > > > >> > > > >> > > > >> > > > >> > > > --- In k5synth@yahoogroups.com, "antdes45dragonmaster" >> > > <antdes45@n...> >> > > > wrote: >> > > > > Digital Ground is plugged to one bridge's negative pole and >> > > analog to >> > > > > 0v line of the transformer(Black wire). I know it's a noisy >ground >> > > > > because when I transfer MIDI between K5 and computer, I hear >some >> > > low >> > > > > volume beeps in the noise, and my intermittent inverter >whines(Is >> > > on >> > > > > DGround) in the headphones when it wants. I looked at the >> > > schemes, and >> > > > > every different PCB's DGrounds are plugged together on the PSU >> > > > > mainboard, but are going to it thru different wires.(Same for >> > > > > AGround). Problem is I don't remember how to filter ground. >> > > Something >> > > > > to try. Also, when I unplug the brown socketed black bus wire >> > > going to >> > > > > outputs board, there is no signal from the headphones, but still >> > > > > noise. So it's not coming from the opamps(Headphones noise). >> > > Might be >> > > > > that the LM386's ground has no filter. While for the rear >outputs >> > > > > noise, the opamps might be too noisy(-45dB with some TL072 >> > > instead of >> > > > > some TL062, which might have not changed anything noise talking, >> > > using >> > > > > some OPA????, don't remember which, will have to re-find the >name >> > > on >> > > > > DIYAudio, might be a lot less noisy, because a signal passing 4 >> > > times >> > > > > in pretty noisy OpAmps in series might not be really good). >> > > > > >> > > > > --- In k5synth@yahoogroups.com, "nelsonj_sce" <nelsonj_sce@y...> >> > > wrote: >> > > > > > It looks like you have already changed out the op-amps and >> > > found that >> > > > > > the noise is still there. Have you tried anythink to fix the >> > > noisy >> > > > > > ground? Is it that the digital and analog all share the same >> > > ground? >> > > > > > Is there a way to "split" the ground or add a new ground plane >> > > and >> > > > > > reroute say the digital chips to the new ground plane? >Are all >> > > the >> > > > > > analog parts on a single board so that we could just cut the >> > > ground to >> > > > > > that board and then wire up a new, "independent" ground? Are >> > > there >> > > > > > just a few key digital parts that are creating the noise that >> > > can be >> > > > > > rerouted to a seperate ground plane? >> > > > > > >> > > > > > Has anyone at Kawai told you how to solve this problem? Even >> > > if I can >> > > > > > get a hold of the schematics, if Kawai or others can >identify a >> > > few >> > > > > > key components it should not be that hard to create a seperate >> > > ground >> > > > > > for those parts. >> > > > > > >> > > > > > Any thoughts? >> > > > > > >> > > > > > --- In k5synth@yahoogroups.com, Antoine Desch\ufffdnes >> > > <antdes45@n...> >> > > > wrote: >> > > > > > > The LM386 doesn't produce any noise. Even if you unplug the >> > > signal >> > > > > > there >> > > > > > > will still be some. Sctually the problem is a noisy ground. >> > > It's >> > > > > > sharing >> > > > > > > the same ground for all the board(s). >> > > > > > > >> > > > > > > nelsonj_sce@y... a \ufffdcrit: >> > > > > > > >> > > > > > > > Here is the latest, it is good news. >> > > > > > > > >> > > > > > > > Today I got my parts for DigiKey. As below I replaced my >> > > > backlight >> > > > > > > > with a blue backlight from nightlaunch. It worked with my >> > > > stock K5 >> > > > > > > > inverter. However, my stock inverter was very flakey, >even >> > > > after I >> > > > > > > > did the resolder job so I decided to replace the stock >> > > > inverter with >> > > > > > > > the DigiKey part. (Digikey part #289-1032-ND). The good >> > > news >> > > > > is that >> > > > > > > > inverter works (even though it is only about 95V @ about >> > > > 550Hz). It >> > > > > > > > is a slightly different color than before, but it still >> > > looks >> > > > great. >> > > > > > > > Also- THERE IS VIRTUALLY NO HUM! >> > > > > > > > >> > > > > > > > The only warning is the Digikey part is not the exact same >> > > size >> > > > > as the >> > > > > > > > original inverter - it is a bit smaller in footprint and a >> > > lot >> > > > > > > > shorter. The stock inverter has only three connections >> > > (in - >> > > > out - >> > > > > > > > ground) and the new inverter has a fourth pin for >mounting. >> > > > Because >> > > > > > > > the part is smaller, I used the original hole for >> > > the "out", but >> > > > > I had >> > > > > > > > to wire up jumpers to the "ground" and the "in" - not >a big >> > > > deal but >> > > > > > > > it is some extra work - and you don't want to see >pictures >> > > of >> > > > > my ugly >> > > > > > > > job. :). But so far so good. >> > > > > > > > >> > > > > > > > Also, I did the 147K resistor hack and it seems to >have gone >> > > > > well. My >> > > > > > > > K5 is a louder, but the headphones have even more noise >> > > now. >> > > > I have >> > > > > > > > been looking things over and I think the headphone >noise is >> > > > because >> > > > > > > > they use a cheap LM386 op-amp and a bad overall design for >> > > the >> > > > > > > > headphone amp. I am trying to see if I can replace this >> > > with a >> > > > > better >> > > > > > > > op-amp, otherwise I think the only good solution is to >just >> > > bypass >> > > > > > > > their circuit completely and make a better headphone >amp and >> > > > wire it >> > > > > > > > up to the K5. >> > > > > > > > >> > > > > > > > Anyway, again the good news is that for less than $30 >> > > > delivered you >> > > > > > > > can get nightlaunch backlight and a Digikey inverter and >> > > have >> > > > a new >> > > > > > > > backlight that does not hum! :) >> > > > > > > > >> > > > > > > > Now for the headphone amp... >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > --- In k5synth@yahoogroups.com, "nelsonj_sce" >> > > <nelsonj_sce@y...> >> > > > > > wrote: >> > > > > > > > > Update: >> > > > > > > > > Well today I ordered a new inverter from >> > > www.DigiKey.com. I >> > > > > > found an >> > > > > > > > > inverter that looks like it will do the job - for those >> > > > interested >> > > > > > > > it is: >> > > > > > > > > >> > > > > > > > > Digikey part # 289-1032-ND and it only cost >$11.90 - >> > > not >> > > > > bad. >> > > > > > > > > >> > > > > > > > > I am not sure if it will fit exactly in the same >slots as >> > > the >> > > > > > original >> > > > > > > > > inverter so it might require some additional wiring. >> > > > > > > > > >> > > > > > > > > Anyway, I had my K5 open to look at the power supply to >> > > plan >> > > > > the new >> > > > > > > > > inverter install when my K5 started "humming", and guess >> > > what, >> > > > > I now >> > > > > > > > > have a beautiful blue backlight. It looks great, a very >> > > cool >> > > > > blue. >> > > > > > > > > So it appears my inverter was not bad, but it just >has bad >> > > > solder >> > > > > > > > > joints. It is working for now but tomorrow I will >likely >> > > take >> > > > > > out the >> > > > > > > > > board and redo all the solder joints. >> > > > > > > > > >> > > > > > > > > Just some additional info I learned in researching >> > > > backlights and >> > > > > > > > > inverters. The "brightness" of the backlight is a >> > > function >> > > > of the >> > > > > > > > > voltage and frequency applied to the backlight. It >> > > appears one >> > > > > > has a >> > > > > > > > > lot of flexibility in selecting the inverter output >> > > voltage and >> > > > > > freq. >> > > > > > > > > For example, nightlauch says you can "test" the >backlight >> > > by >> > > > > > plugging >> > > > > > > > > it directly in to a wall socket (120V AC @ 60 Hz here in >> > > the >> > > > > > US)! The >> > > > > > > > > higher the voltage and freq the brighter the backlight. >> > > > > > However, the >> > > > > > > > > backlight will "burn out" quicker the higher the freq. >> > > So there >> > > > > > is a >> > > > > > > > > trade off, high freq = bright but shorter life. >> > > > > > > > > >> > > > > > > > > Right now my stock inverter is putting out about 102V @ >> > > 380 >> > > > Hz. I >> > > > > > > > > think the inverter I ordered will put out about 95V >@ 540 >> > > Hz and >> > > > > > > > > should work with a 3 - 6 V DC input. >> > > > > > > > > >> > > > > > > > > Next step, 147k resistors (also ordered from Digikey >> > > today). >> > > > > > > > > >> > > > > > > > > >> > > > > > > > > >> > > > > > > > > --- In k5synth@yahoogroups.com, "nelsonj_sce" >> > > <nelsonj_sce@y...> >> > > > > > wrote: >> > > > > > > > > > Well I replaced my backlight with one I ordered from >> > > > > > > > > www.nightlaunch.com. >> > > > > > > > > > >> > > > > > > > > > It took less than two weeks from when I ordered >and the >> > > > > parts look >> > > > > > > > > good. >> > > > > > > > > > >> > > > > > > > > > Good news/bad news though on my backlight. >> > > > > > > > > > >> > > > > > > > > > The good news: I had no problems removing the LCD, >> > > taking out >> > > > > > the old >> > > > > > > > > > backlight and sliding in the new backlight. The new >> > > light has >> > > > > > some >> > > > > > > > > > wires and a plastic "tab" that kind of gets in the >way, >> > > so I >> > > > > > soldered >> > > > > > > > > > the backlight wires to where the wires connect to the >> > > LCD >> > > > board. >> > > > > > > > > > Hint:You have to cut the new backlight to size, so >make >> > > the >> > > > > > backlight >> > > > > > > > > > a little longer (say 1/4 inch) than the original >to make >> > > > things >> > > > > > > > easier. >> > > > > > > > > > >> > > > > > > > > > Bad news: My backlight does not work but I think my >> > > inverter >> > > > > > is the >> > > > > > > > > > problem. I am only getting about 1/2 Volt at the >> > > output of my >> > > > > > > > > > inverter, and I am supposed to get 120V @400Hz if I >> > > > > understand the >> > > > > > > > > > part correctly. I tested my inverter before I did the >> > > > backlight >> > > > > > > > > > install and saw it had low voltage, but I was hoping >> > > that my >> > > > > > existing >> > > > > > > > > > "dead" backlight was causing the problem (i.e. it was >> > > > > shorted.) I >> > > > > > > > > > guess not because even with the new backlight I get >> > > very low >> > > > > > voltage. >> > > > > > > > > > >> > > > > > > > > > Anyway, it looks like I need to get an inverter. >I can >> > > get an >> > > > > > > > > > inverter from nightlaunch for $17.99+s/h but it >needs 9V >> > > > DC. I >> > > > > > > > > > understand the inverter in the K5 uses 5V DC. >> > > > > > > > > > >> > > > > > > > > > Q1: Does the K5 inverter use 5V DC? >> > > > > > > > > > Q2: If I measure the voltage on the two wires to the >> > > left >> > > > of the >> > > > > > > > > > inverter, should I get 120V if everything is working? >> > > (My >> > > > > > Fluke says >> > > > > > > > > > it is good <=1kHz) >> > > > > > > > > > Q2: Does anyone know where to get a compatible K5 >> > > inverter >> > > > > and how >> > > > > > > > > > much it will cost? >> > > > > > > > > > >> > > > > > > > > > Thanks again for all the help. This group is great. >> > > > > > > > >> > > > > > > > >> > > > > > > > Yahoo! Groups Sponsor >> > > > > > > > ADVERTISEMENT >> > > > > > > > >> > > > > > >> > > > > >> > > > >> > > ><http://us.ard.yahoo.com/SIG=129jk20o5/M=273541.4247512.5496808.224846 >> > > 7/D=g= >> > > > > = >> > > > > > >> > > > > >> > > > >> > > >rplch/S=1705032144:HM/EXP=1095918198/A=2061551/R=0/SIG=11sr5b9n1/*http >> > > ://la= >> > > > > u= >> > > > > > nch.yahoo.com/artist/videos.asp?artistID=1001301> >> > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > > > >> > > > > > >> > > > >-------------------------------------------------------------------- >> > > ---- >> > > > > > > > Yahoo! Groups Links >> > > > > > > > >> > > > > > > > * To visit your group on the web, go to: >> > > > > > > > http://groups.yahoo.com/group/k5synth/ >> > > > > > > > >> > > > > > > > * To unsubscribe from this group, send an email to: >> > > > > > > > k5synth-unsubscribe@yahoogroups.com >> > > > > > > > >> > > > > <mailto:k5synth-unsubscribe@yahoogroups.com?subject=Unsubscribe> >> > > > > > > > >> > > > > > > > * Your use of Yahoo! Groups is subject to the Yahoo! >> > > Terms of >> > > > > > > > Service <http://docs.yahoo.com/info/terms/>. >> > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > > -- >> > > > > > > antdes45@n... >> > >> > >> > >> > >> > Yahoo! Groups Sponsor >> > ADVERTISEMENT >> > ><http://us.ard.yahoo.com/SIG=129v1c9qu/M=315388.5455589.6541277.2248467/D=grplch/S=1705032144:HM/EXP=1097390067/A=2372349/R=0/SIG=12idgqpgc/*https://www.orchardbank.com/hcs/hcsapplication?pf=PLApply&media=EMYHNL40WL1004SS> > >> > >> > >> > >> > >------------------------------------------------------------------------ >> > Yahoo! Groups Links >> > >> > * To visit your group on the web, go to: >> > http://groups.yahoo.com/group/k5synth/ >> > >> > * To unsubscribe from this group, send an email to: >> > k5synth-unsubscribe@yahoogroups.com >> > <mailto:k5synth-unsubscribe@yahoogroups.com?subject=Unsubscribe> >> > >> > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of >> > Service <http://docs.yahoo.com/info/terms/>. >> > >> > >> >> -- >> >> Antoine Desch\ufffdnes /aka >> -\ufffd\ufffd`-\ufffd-DragonMaster-\ufffd-\ufffd\ufffd`- >> http://thehotcom.deep-ice.com/ >> Files: http://www.angelfire.com/ca7/hotcomcenter/ > > > > -- Antoine Desch\ufffdnes aka DragonMaster http://thehotcom.deep-ice.com/ Files:http://angelfire.com/ca7/hotcomcenter/ __________________________________________________________________ Switch to Netscape Internet Service. As low as $9.95 a month -- Sign up today at http://isp.netscape.com/register Netscape. Just the Net You Need. New! Netscape Toolbar for Internet Explorer Search from anywhere on the Web and block those annoying pop-ups. Download now at http://channels.netscape.com/ns/search/install.jsp
Message
RE: [k5synth] Notes on Schems...
2004-10-15 by antdes45@netscape.net