Guest drumma Report post Posted October 7, 2004 the wires underneath the perfboard are actually those wires in a reel right? like u buy a reel of silver wires.. is it those? Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 Drumma, Please dont use gain of 11, it's overkill. check this out: Dual Opamp Singale Opamp For 1st timer, i would recommend to work with Single Opamp. the reason is the soldering points are not so concentrated at one region (around the opamp). I would not recommend copper strips board, unless you have a hand drill to cut the copper path. (i have hard time to work with it ) Pls buy high quality parts for your amp, it's easier to work with. okies, for the HDP, i think i know how the circuit is being connected but i still dun understand a few things.. maybe u can explain to me? the L-out and and R-out means go where? and what is the 1m? thanks Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 (edited) the wires underneath the perfboard are actually those wires in a reel right? like u buy a reel of silver wires.. is it those? According to the pic, the red colour lines are bare wires and pink ones are insulated wire. silver wire for CMOY Edited October 7, 2004 by huangyong Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 the wires underneath the perfboard are actually those wires in a reel right? like u buy a reel of silver wires.. is it those? According to the pic, the red colour lines are reel wires and pink ones are insulated wire. silver wire for CMOY hmm, so what's the diff btw the both of them? Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 the wires underneath the perfboard are actually those wires in a reel right? like u buy a reel of silver wires.. is it those? According to the pic, the red colour lines are reel wires and pink ones are insulated wire. silver wire for CMOY hmm, so what's the diff btw the both of them? The insulated wires are needed as flying wire. The reason: when bare wires touch each other, they will short the circuit, while the insulated wires won't. Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 hmm.. ok.. regarding the gain, is there any recommended gain certain opamps or high impedance and low impedance headphones? Share this post Link to post Share on other sites
jtfoo 0 Report post Posted October 7, 2004 Drumma, okies, for the HDP, i think i know how the circuit is being connected but i still dun understand a few things.. maybe u can explain to me? the L-out and and R-out means go where? and what is the 1m? thanks logically L-out, R-out, goes to headphoe jack. 1m?? If it's the 1M, then it's the input impedance. 1 megaohms Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 so what does the input impedance do? is there a guideline for it to be at certain value? Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 (edited) it will function as a High-Pass Filter, which means it will cut off the low frequency. The formula is: 1 / 2*Pie*R2*C1 = cut off frequency. Gain = 1 + R4/R3 Edited October 7, 2004 by huangyong Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 oh my god, is this a different design? Share this post Link to post Share on other sites
bpribadi 0 Report post Posted October 7, 2004 (edited) hmm.. ok.. regarding the gain, is there any recommended gain certain opamps or high impedance and low impedance headphones? so what does the input impedance do? is there a guideline for it to be at certain value? Young man, seems like you haven't read my explanation in the DIY session: http://www.sgheadphones.net/index.php?showtopic=2718&st=30 You can use gain 6.6 for low Z headphone, use the combination of 5.6k and 1k resistor. For input, you can use 100k pot and 1M resistor (R2). Read more please Edited October 7, 2004 by bpribadi Share this post Link to post Share on other sites
jtfoo 0 Report post Posted October 7, 2004 Drumma, I think you should start afresh with this thread. Forget what's input impedance, what's high pass filter, what insulated wire ..etc at the moment. concentrate what you need to built the amp first. Physically all those red blue line can use be the same wire. Don't get into cable selection until you have progress further. Resistors/ caps can get from Sim lim tower. Forget about audio grade one first. Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 oh my god, is this a different design? this is the original design by Chu Moy. the HDP is design by digi01. Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 no, i'm not talking bout grade A cables or selection of cables. i'm just wondering what is used to connect in between the resistors and everything in there. i hope u guys hope where i'm coming from. i'm not someone who understands what the pictures really really meant. and i can't find any site which teaches me how to read those? pm me if u have any links? thanks for all the patience.. Share this post Link to post Share on other sites
bpribadi 0 Report post Posted October 7, 2004 Aahhh my friend, sorry for that... we thought you have some background to understand it. Do you understand the CMoy diagram after seeing the picture above? Here is a good link to start learning: http://www.tpub.com/content/neets/index.htm Share this post Link to post Share on other sites