Loading ...
Sorry, an error occurred while loading the content.
 

Re: Notes on Schems...update on grounding experiment

Expand Messages
  • antdes45dragonmaster
    Also, I get some -47 when the volume isn t even at max. So I ll give a try to these OPA4228, and the 2 chan version in some preamps and DACs. ... the line in
    Message 1 of 41 , Nov 10, 2004
      Also, I get some -47 when the volume isn't even at max. So I'll give a
      try to these OPA4228, and the 2 chan version in some preamps and DACs.

      --- In k5synth@yahoogroups.com, antdes45@n... wrote:
      > My mixer plugged to the line in gives me -55 and my K5 plugged to
      the line in gives me -55 too. I did the 147k hack but with 150k ones,
      I got a problem: the last 1/12 boosts the volume x3, and when I switch
      up and down from the 11/12 to the 12/12 part, I hear a pop between
      them(BTW it doesn't distort, except for crappy low W headphones.
      >
      > "nelsonj_sce" <nelsonj_sce@y...> wrote:
      >
      > >
      > >OK - I am note sure this is an apples-to-apples test but here is what
      > >I did. I have a Yamaha DSP2416 mixer in my computer. I hooked up my
      > >K5 to the mixer and then read the levels from the mixer.
      > >
      > >I did all tests while my K5 was in multi mode, I tested both the "mix"
      > >output and the "1" output and turned the mixer channel on my computer
      > >all the way up. I did not hit any notes, so I was just looking at the
      > >noise level, and I did not run through any FX or noise gates, I just
      > >ran the K5 direct to the mixer.
      > >
      > >Results:
      > >
      > >1) With the K5 volume at minimum I was below -72dB on both "mix" and
      > >"1" outputs. This was the same reading as when the K5 was not even
      > >plugged in, so there was no additional noise.
      > >
      > >2)With the K5 volume at MAX, the "Mix" output was just above -66dB and
      > >the "1" output was just above -72dB. NOTE: I did the 147k resistor
      > >hack, so my MAX output is much hotter than a stock K5.
      > >
      > >I am not sure how my K5 would do if I used the same setup you used,
      > >but this was the best I could do with the equipment I have. I hope
      > >this helps.
      > >
      > >
      > >
      > >
      > >
      > >
      > >--- In k5synth@yahoogroups.com, Antoine Deschênes <antdes45@n...>
      wrote:
      > >> Could you do a little VU meter test, with mix output if you have
      > >changed
      > >> the opamp for it(The same opamp is for headphones) or single if not,
      > >> without a noise gate or anything else at minimum volume? I'd like to
      > >> know how many dBs is it now.(I sat my SBLive VOL adj. at -90dB on
      > >the VU
      > >> meter(Software) without anything plugged in the Live, then
      plugged the
      > >> K5 in the Line In and i got a -47dB.
      > >>
      > >> nelsonj_sce@y... a écrit:
      > >>
      > >> >
      > >> > Hack update:
      > >> > Since my last note I replaced the other two op-amps with
      socketed Burr
      > >> > Brown OPA4228. Replacing these two other op-amps did reduce noise
      > >> > levels noticeably. There is still some noise but with 1)the these
      > >> > four super clean op-amps, 2)using Multi, 3)routing everything to a
      > >> > sinlge output on the multi rather than mix, and 4)using my
      noise gate,
      > >> > noise is really not an issue any more. I would love to try and
      > >> > replace the VCAs also, but I have not been able to track down a
      spec
      > >> > sheet (or any other info on the) on them so I do not have a clue as
      > >> > what might works as an upgraded part.
      > >> >
      > >> > If anyone can help, the VCAs are part M5222L and they are from
      > >> > the same off-brand Japanese JRC company that is used elsewhere
      in the
      > >> > K5. If anyone can help me with details on the M5222Ls I will
      see if I
      > >> > can find a replacement parts.
      > >> >
      > >> > My bottom line: If you are willing to lay-out $30 for the four BB
      > >> > OPA4228 and sockets, and you if you are willing to remove some
      > >> > tough-to-remove parts, I highly recommend this op-amp replacement
      > >> > hack. My K5 has much less noise and just sounds much
      warmer/classier
      > >> > with the new parts. I would love remove more noise, but right
      now it
      > >> > sounds very good and I am not very motivate to continue
      hacking. (I
      > >> > do still plan on replacing the headphone circuit though since I
      > >> > already made the new circuit and all I have to do is wire it up.)
      > >> >
      > >> > An interesting aside: After I did the latest op-amp replacement,
      > >> > everything sounded great in multi, but when I went to single I had
      > >> > serious problems. Various ranges of the keyboard worked fine,
      while
      > >> > other ranges sounds like a fried amp circuit. It turns out
      that while
      > >> > I was removing IC8 I accidentally pulled part of the circuit board
      > >> > trace off that connected pins 1 and 2 on IC8. This trace
      provides the
      > >> > feedback loop between the (-) and output of line G2. Once I
      tracked
      > >> > down the problem I was able to reconnect pins 1 and 2 and then
      > >> > everything in single mode worked great. What I conclude from
      this is
      > >> > that the K5 in single mode is splitting different ranges of the
      > >> > keyboard to different op-amps. I am not sure what K% is doing in
      > >> > multi but multi (ouput 1) DOES NOT use the opamp in IC8 pins 1-2-3.
      > >> >
      > >> > Hack on.
      > >> >
      > >>
      > >>
      > >> --
      > >> antdes45@n...
      > >
      > >
      > >
      > >
      >
      >
      > --
      > Antoine Deschênes
      > 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
    • antdes45dragonmaster
      Also, I get some -47 when the volume isn t even at max. So I ll give a try to these OPA4228, and the 2 chan version in some preamps and DACs. ... the line in
      Message 41 of 41 , Nov 10, 2004
        Also, I get some -47 when the volume isn't even at max. So I'll give a
        try to these OPA4228, and the 2 chan version in some preamps and DACs.

        --- In k5synth@yahoogroups.com, antdes45@n... wrote:
        > My mixer plugged to the line in gives me -55 and my K5 plugged to
        the line in gives me -55 too. I did the 147k hack but with 150k ones,
        I got a problem: the last 1/12 boosts the volume x3, and when I switch
        up and down from the 11/12 to the 12/12 part, I hear a pop between
        them(BTW it doesn't distort, except for crappy low W headphones.
        >
        > "nelsonj_sce" <nelsonj_sce@y...> wrote:
        >
        > >
        > >OK - I am note sure this is an apples-to-apples test but here is what
        > >I did. I have a Yamaha DSP2416 mixer in my computer. I hooked up my
        > >K5 to the mixer and then read the levels from the mixer.
        > >
        > >I did all tests while my K5 was in multi mode, I tested both the "mix"
        > >output and the "1" output and turned the mixer channel on my computer
        > >all the way up. I did not hit any notes, so I was just looking at the
        > >noise level, and I did not run through any FX or noise gates, I just
        > >ran the K5 direct to the mixer.
        > >
        > >Results:
        > >
        > >1) With the K5 volume at minimum I was below -72dB on both "mix" and
        > >"1" outputs. This was the same reading as when the K5 was not even
        > >plugged in, so there was no additional noise.
        > >
        > >2)With the K5 volume at MAX, the "Mix" output was just above -66dB and
        > >the "1" output was just above -72dB. NOTE: I did the 147k resistor
        > >hack, so my MAX output is much hotter than a stock K5.
        > >
        > >I am not sure how my K5 would do if I used the same setup you used,
        > >but this was the best I could do with the equipment I have. I hope
        > >this helps.
        > >
        > >
        > >
        > >
        > >
        > >
        > >--- In k5synth@yahoogroups.com, Antoine Deschênes <antdes45@n...>
        wrote:
        > >> Could you do a little VU meter test, with mix output if you have
        > >changed
        > >> the opamp for it(The same opamp is for headphones) or single if not,
        > >> without a noise gate or anything else at minimum volume? I'd like to
        > >> know how many dBs is it now.(I sat my SBLive VOL adj. at -90dB on
        > >the VU
        > >> meter(Software) without anything plugged in the Live, then
        plugged the
        > >> K5 in the Line In and i got a -47dB.
        > >>
        > >> nelsonj_sce@y... a écrit:
        > >>
        > >> >
        > >> > Hack update:
        > >> > Since my last note I replaced the other two op-amps with
        socketed Burr
        > >> > Brown OPA4228. Replacing these two other op-amps did reduce noise
        > >> > levels noticeably. There is still some noise but with 1)the these
        > >> > four super clean op-amps, 2)using Multi, 3)routing everything to a
        > >> > sinlge output on the multi rather than mix, and 4)using my
        noise gate,
        > >> > noise is really not an issue any more. I would love to try and
        > >> > replace the VCAs also, but I have not been able to track down a
        spec
        > >> > sheet (or any other info on the) on them so I do not have a clue as
        > >> > what might works as an upgraded part.
        > >> >
        > >> > If anyone can help, the VCAs are part M5222L and they are from
        > >> > the same off-brand Japanese JRC company that is used elsewhere
        in the
        > >> > K5. If anyone can help me with details on the M5222Ls I will
        see if I
        > >> > can find a replacement parts.
        > >> >
        > >> > My bottom line: If you are willing to lay-out $30 for the four BB
        > >> > OPA4228 and sockets, and you if you are willing to remove some
        > >> > tough-to-remove parts, I highly recommend this op-amp replacement
        > >> > hack. My K5 has much less noise and just sounds much
        warmer/classier
        > >> > with the new parts. I would love remove more noise, but right
        now it
        > >> > sounds very good and I am not very motivate to continue
        hacking. (I
        > >> > do still plan on replacing the headphone circuit though since I
        > >> > already made the new circuit and all I have to do is wire it up.)
        > >> >
        > >> > An interesting aside: After I did the latest op-amp replacement,
        > >> > everything sounded great in multi, but when I went to single I had
        > >> > serious problems. Various ranges of the keyboard worked fine,
        while
        > >> > other ranges sounds like a fried amp circuit. It turns out
        that while
        > >> > I was removing IC8 I accidentally pulled part of the circuit board
        > >> > trace off that connected pins 1 and 2 on IC8. This trace
        provides the
        > >> > feedback loop between the (-) and output of line G2. Once I
        tracked
        > >> > down the problem I was able to reconnect pins 1 and 2 and then
        > >> > everything in single mode worked great. What I conclude from
        this is
        > >> > that the K5 in single mode is splitting different ranges of the
        > >> > keyboard to different op-amps. I am not sure what K% is doing in
        > >> > multi but multi (ouput 1) DOES NOT use the opamp in IC8 pins 1-2-3.
        > >> >
        > >> > Hack on.
        > >> >
        > >>
        > >>
        > >> --
        > >> antdes45@n...
        > >
        > >
        > >
        > >
        >
        >
        > --
        > Antoine Deschênes
        > 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
      Your message has been successfully submitted and would be delivered to recipients shortly.