Guest drumma Report post Posted October 7, 2004 Hi all, i've been wanting to do a DIY amp myself and i hope that u guys can help me.. dun ask me why i want to do a cMOY k? , thanks. i hope that u guys can help me with this topic. Firstly, i don't know what are the things needed to build a cMOy? so any kind souls mind listing it down for me? i'm quite blurred when i read tangentsoft.. yah? thanks! Secondly, there's this schemetic(correct me if i'm wrong) i always see in cMOY threads.. it's this diagram with 5 resistors and one opamp(if i'm not wrong) in the centre.. so is it that i follow the diagram and solder those in the circuit board? Thirdly, is there a recommended gain for certain impedance headphones? is it like gain level 11 for >120ohms headphones and 5 for <120? pls guide me and correct me i'm wrong. thanks in advance for all the help! cheerios, Li Ji Share this post Link to post Share on other sites
heady 0 Report post Posted October 7, 2004 Hi drumma, you must search for the type of perf board used in the Tangent which is hard to find in Singapore. I found using the type with straight copper strips easiest to use but you need to have a way to cut the strips where you don't want it to connect. If you are doing this first time, better to stick to the gain used for the example, ie gain of 11. Later when you are better, you can try changing the gain. Just my 0.02 worth. Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 okies.. can u guide me like tell me what PCB(where can i get) should i use and the things needed like what capacitors, resistors or what? thanks alot! Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 update.. i saw this in headwize.. is it something like this? http://headwize.com/ubb/showpage.php?fnum=3&tid=5129 Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 (edited) 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. Edited October 7, 2004 by huangyong Share this post Link to post Share on other sites
bpribadi 0 Report post Posted October 7, 2004 For CMoy, you can use strip board or perforated board (holes only). Share this post Link to post Share on other sites
jtfoo 0 Report post Posted October 7, 2004 huangyong, I think the volume pot wired wrongly... Input should be on the right most pin, gnd on the left most pin. Unless you're the unconvetional type who like to up the volume with anti-clockwise turn. Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 Sijosae's Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 I copy that from headwize.com.. Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 Single to Dual Adapter. Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 (edited) sorries if this is a very silly qns. what do i use to connect to the battery to the opamps and everything? wires? i dun quite understand ur circuit huangyong, is it using a board or something?what does it mean by single to dual adapter? thanks Edited October 7, 2004 by drumma Share this post Link to post Share on other sites
jtfoo 0 Report post Posted October 7, 2004 I copy that from headwize.com.. Someone from headwize must have like to turn anti-clockwise to up the volume. Anyway the sijosae's connection is the correct for normal people, IN to the right most pin, GND to the left most pin, with the shaft orientation on top. Share this post Link to post Share on other sites
huangyong 0 Report post Posted October 7, 2004 (edited) Which one are you refering to? i think i posted too many pics, quite confusing.. but a pic can tell a thousand words.. the layout by Sijosae is using perfboard, which has holes only. what does it mean by single to dual adapter? if you want to use single opamps(e.g OPA627) on the layout provided by Sijosae, you need to use the adapter to convert 2 single channel opamps into one dual channel opamp. Edited October 7, 2004 by huangyong Share this post Link to post Share on other sites
Guest drumma Report post Posted October 7, 2004 u know where can i get the perfboard/ Share this post Link to post Share on other sites
jtfoo 0 Report post Posted October 7, 2004 Which one are you refering to? i think i posted too many pics, quite confusing.. but a pic can tell a thousand words.. The 1st two pictures that says 'Pocket Cmoy HDP' Share this post Link to post Share on other sites