tropicalrips 0 Report post Posted March 6, 2004 (edited) my first attempt at point to point soldering not a clone as i added a 2200uF cap on the power side to reduce the on/off "pop" sound, it work when i switch off the amp, the music fades away after about 2 secs, but the pop is still there when i turn it on. the case is a Hammond translucent blue, i also hav a smaller version of the same case, planning to use that for an A47 shot of the back , i used RCA jacks as there was enough space in the case the volume pot is the mini blue Alps, knob is from RS. there no mounting for the parts in the case, everything is kind of "jam" together i use 3M tape to hold the 2 Solen caps together, the big power cap just kind of sits nicely between the Solens, the cover of the case also press down on all the components, so everything is quite stable in there shot with the cover on, i wonder if u can get somthing like this though airport security anyone tried it before i did not take pics of the point to point soldering as they were not very neat maybe my second try will be better sound wise, it sounds good with Grado not as colored like my variants, very good slam, on the whole a different type of sound, transparent sound from a transparent amp Edited March 8, 2004 by tropicalrips Share this post Link to post Share on other sites
av98m 0 Report post Posted March 6, 2004 the problem with all these diy amps is that they look like home made bombs! Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted March 6, 2004 still had some time left, so i made a mini stereo to RCA cable for portable use done with cheap parts here seen here with the new amp and PCDP, i think the cable makes it look even more like a bomb Share this post Link to post Share on other sites
Q00 0 Report post Posted March 6, 2004 Are u saying that the sound is very neutral and has a lot of bass energy? Sounds like a winner to me Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted March 6, 2004 Are u saying that the sound is very neutral and has a lot of bass energy? Sounds like a winner to me i don't really know how to explain it, but it still has the bass kick of a cmoy, but the details are better. op-amp is NJM4556 only problem now is the startup "pop" sound, i measure the dc on the output and its only 1.1 to 2.3 mV, so i guess this should still be quite safe for headphones yet to try it with other headphones, so far only tried it with SR-80 & sporta pro Share this post Link to post Share on other sites
Q00 0 Report post Posted March 6, 2004 i suppose the increased detail is due to the faster op-amp which u mentioned in another thread. btw, i really like the diy look of the cables. the hammond case is really beautiful to boot... the alps blue looks perfect on it. Share this post Link to post Share on other sites
hacknet 0 Report post Posted March 7, 2004 i don`t know if this would work, but you could try putting diodes across the switches to remove the popping, if i`m not wrong, this is possible as long it is DC. Batt(+)----------*switch*--------(+) | | ------<|------- Share this post Link to post Share on other sites
N@Z 0 Report post Posted March 7, 2004 The 'POP' sound also occurs on the Grado RA-1 so it's not really a big problem. Even my META amp makes that sound although to a slightly lesser extent. Share this post Link to post Share on other sites
hacknet 0 Report post Posted March 7, 2004 its caused by the back emf caused by a inductor and a capacitor charging each other up when the switch is closed. these emf spikes can be quite nasty. Share this post Link to post Share on other sites
Q00 0 Report post Posted March 7, 2004 Is this back emf very harmful? Share this post Link to post Share on other sites
hacknet 0 Report post Posted March 7, 2004 it could be... but, if you are running batteries, you shouldn`t destroy anything. Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted March 7, 2004 i don`t know if this would work, but you could try putting diodes across the switches to remove the popping, if i`m not wrong, this is possible as long it is DC. Batt(+)----------*switch*--------(+) | | ------<|------- hacknet, i'm not sure what u mean with the diodes...but i'm game to try anything do u mean adding the diodes on the switch before the power pins of the op-amp? my NACA is following the ra-1 clone specs/values except the Electrolytic cap across the power rails, this removes the shut-off "pop" but does not help when i turn on the amp. Share this post Link to post Share on other sites
huangyong 0 Report post Posted March 8, 2004 hi, nice job!! but for opamp and and discrete base amplifiers, i do not recommend point to point soldering. a well design PCB should serve the job better. this is due to Electromagnetic Interference. a lot of wire mix together will coz stray inductance and capacitance, and may introduce distortion to the signal. unless you use good teflon insulated wire. however, alot of high end tube amp still using p2p soldering. Share this post Link to post Share on other sites
tropicalrips 0 Report post Posted March 8, 2004 update : i found a way round the annoying turn on "pop" i placed a tantalum cap on the ground formed by the 2 batteries before going into the circuit, this reduces the "pop" to a soft "click" sound. i can't tell if the sound of the amp changed, but i don't think it did Share this post Link to post Share on other sites
Q00 0 Report post Posted March 10, 2004 Hey Tropicalrips, Hows the v3 coming along? Have u finished burning it in yet? I wonder how the sound has changed and how long the battery lasts with this version? Share this post Link to post Share on other sites
