Search results

  1. W

    Converting CD-ROM Drive to Audio CD Player/MP3 player!!!

    There is alot of circuit's over the net that does what you want. Here explain why it can't play mp3. http://www.hardwaresecrets.com/article/71 Many others... https://unstable.nl/andreas/cdromdiscman.html http://www.sorgonet.com/trashing/ComputerAudioCDCarPlayer/...
  2. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, Did a few more experiences with the circuit and have found a document that show me part of the solution for the problem: http://tangentsoft.net/audio/hs-opamp.html Paying close attention to the distortion it has to do with the bass of the sound, removing R5/R22 and replacing with...
  3. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Thank you, i will fix that  ;D
  4. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Thank you audioguru. Any light on the strange distortion? Tell me something, if you run the tests again with some capacitance load wht and without the buffers, will the performance be the same? Thank you again!
  5. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, I dont know if "cracking" was the correct name of that but if your hear only the right channel you will listen something "cracky" or "cranky" distortion, i dont know the exact name, sorry. The strange is that distortion is coming from R5 and R22, looks like a "Feedback Noise"...
  6. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, Tell me something, do you know what is happening with this sample? http://www.sendspace.com/file/f2fh8j (1.2Mb) Looks like the sound is cracking up at the both ambience channels, the voice channel is fine, this is one of the "special situations" because the circuit works great...
  7. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Do you still have SQ vinil records? I was reading a page about Quadraphonics here, maybe you will like. I've never heard any type of vinyl records that uses technology like that, SQ, Quadradisc, Q4, Quad-8, Quadraphonic Stereo etc. http://en.wikipedia.org/wiki/Quadraphonic But i know from...
  8. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, Sound like mission accomplished to me.  ;D I enjoy listen to this haffler in my car, and you told me that you have build one your self right? Thank you again audioguru.
  9. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    So, here is the sample with the double buffer configuration and all the changes. http://www.sendspace.com/file/0syxro (2Mb) The distortion was noticed at the beggining when there is something that sound like a pipe organ, moust of the time there was a distortion. But with the new virtual ground...
  10. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, I'm using a comercial PSU (regulated at 12V/1A), i know that is is very stable, and i'm sure that the problem is the virtual ground, it has to be stable at 1/2 Vcc or i will get the distortion problems, messing up with the values shows that. But your virtual ground solution works...
  11. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    So, moment of truth. I've made a few tests with exacly same components as your virtual ground design, it was almost. I pushed the circuit limits by the way, so instead of 2.3Vpp signal i use a 5.0Vpp signal to push it to the limit and to meet the specifications that i will work with. Using this...
  12. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Ok, i will made the changes with your circuit, just give me a minute to work this out.
  13. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, Yes, it was Elvis Presley, the recording was made live at the show from the sound board at 08/12/1970, the original has that distortion and noise, the Buzz, Hum and Shhh. I did not know that the 22nF could overload the opamp but i tought it wold atenuate the high frequency around...
  14. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    I will design the "phanton ground" using a TL072, do you think that this will be enough to make the virtual ground more stable and avoid the distortion?
  15. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Doing frequency analysis response, changing the eletrolitic capacitor from 220uF to 22uF i get a decrease at bass response, sound looks like a dry high frequency and a dull midle to bass response, changing back to 220uF gives a more natural flat sound
  16. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, Changing that R12/13 from 4.7K to 100K makes the sound worse, at the center channel for example, Elvis voice start to crack up soon as he start singing, i used the same 2.3Vpp signal, when we get near to the end all channels has a huge distortion like a guitar overdrive. The...
  17. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hi audioguru, So your sugestion is to increase the resistor values to 100K, decrease the capacitors values and remove the 100K bias resistor? But there is a problem, if i remove the 100K bias resistor i will short the input channels messing up with the effect, right? The buzzing distortion at...
  18. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hello audioguru! How are you, you big dog  (or duck) ;D Thank you, it was not an easy task and i wont let it go that easy ;) I love learning this stuff. 8) So, what you think about the new circuit, it was a brain burning task, you have more experience than me in that area. tell me something...
  19. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hello esp1, how are you? Thank you for your reply The aplication note AN581 (Download here) show a similar circuit with the CA3140. But i really worry about is if this buffered virtual ground will or could hold a 5Vpp RCA signal to prevent audio clipping. At this sample...
  20. W

    Need sugestions about virtual ground or symetric supply for OPAMP

    Hello guys! I was talking with audioguru some time back about my hafler circuit (schematic attached), it was clipping and i did know exactly why, we exchange some ideas and i choose to let it go. I've never used the center channel and when i did the quality was very bad, the overall sound got...
Top