mychew 0 Report post Posted September 29, 2003 Equipment used: Sony D421SP pcdp Monster RCA to mini Cable 400 my low-end Senn HD 202 This is not a review as i had a brief listen to it only and i don't think i'm fit to write a review on that based on my limited listening experience. Below would be my humble thought on the DIY Grado amp. My 2 cents worth comments: i test the amp with secret garden albums- the Dream Catcher. When i listen to the musics...it sounds bright to me. and make to conclude that it is a bright sounding amp. but one thing i notice, if the album u use is bright sounding, it would be even more brighther, there is an album which huangyong let me to try on his gradoamp..i cant remember the artist and album name. but the instrument used is guitar...ok..guitar is bright i agree...but pair with the amp...i really cant say that i can accept that kind of brightness...way too bright for me. for the bass, i can say there is not enough bass...i can say if u pair with akg k501..u would be really disappointed by how it would sounds..even my boomy hd 202 can be made to sound to nearly no bass stage. soundstage wise, it's still quite acceptable. not really wide enough for my taste. but it did not provide me the depth of soundstage. what make me regretted is that i did not test out whether it's a laid-back or forward sounding amp...IIRC..should be a forward-sounding amp...how forward it is...i cant comment, coz i cant remember coz i did not think of this that day!!! i can say it dun have the speed that a nice solidstate amp would have. it's a tad slow..but still not comparable to the slowness of x-cans. the vocal is not that smooth and i think the high has not been reduced or removed much, though huangyong did some mod to roll off the high. for the imaging, i can say, u can still hardly tells out the instruments used if u have listen to it before. but this grado amp cant tell u where those equipments are positioned or placed at. i don't know which word is suitable to decribe it..hmm... when i power on and off the amp..i can notice a "tuck" sound from my cans..one more thing, the amp is grounded to a coint..i wonder this would work. i'm not sure of it.luckily, i cant hear any humming from the amps general speaking, it's just a normal sounding amp except it's a bit slow which would make me like it more...but for its weaknesses that i notice during my brief listen session..or maybe a bit longer than that, i can say i would not go for it. unless i'm really a very new newbie in headfi and have no experience in it, i would still hardly consider of buying this. i think huangyong should mod somemore and make it sounds better maybe can say it's an entry level headamp?hm..maybe can la...though not really up to it loh. but i think it's quite nice already. but i would go for creek instead if u want me to buy the grado but for those pure music lover with a bit interest in getting themselves a headamp, this would be nice for them already, coz they demand good music more...not good sound dun beat me k..coz i really talk too much here already Share this post Link to post Share on other sites
Blues 0 Report post Posted September 29, 2003 interesting.. it doesn't seem to like your senn ? Share this post Link to post Share on other sites
mychew 0 Report post Posted September 29, 2003 lol...no lah...i know my cans is bright..but i can say it's even more brighter than i think. it makes hd 202 even more brighter..pair with x-cans can differentiate it already but x-cans are not really that good too lah..just that i like how it sounds and its performance. it suits my taste better at least it's not so bright now..slow and smooth..though not milky smooth la...i think milky smooth would be really smooth until u cant really use milky to describe it already. make u speechless of the smoothness. at least x-cans make my cans warmer than before...but it's warmer at the bright side and i can liste more and enjoy better...but with the grado...sorry....i dun think so Share this post Link to post Share on other sites
fishball79 0 Report post Posted September 29, 2003 Interesting review. Any pics of the amp? Share this post Link to post Share on other sites
N@Z 0 Report post Posted September 29, 2003 Do you or huangyong have any pictures of the amp? I would be intrested to know how it would sound on other equipment. Share this post Link to post Share on other sites
mychew 0 Report post Posted September 29, 2003 hm..should ask huangyong about it...see he got any photo of it or not...maybe he can snap a photo of it or maybe let me do it Share this post Link to post Share on other sites
fishball79 0 Report post Posted September 29, 2003 (edited) Personally I would only use Grado amp on headphones as easy to drive as grados. Earphones comes to mind... don't think any cans are easier than grados. One main reason is cos the original design uses ONE abysmal opamp to drive both channels. As seen in Gilmore and PPA, they use like half a dozen or more. That means the grado amp can only drive really easy cans well... anything else would be underdriven and the brightness mychew experienced could be due to the lack of power. Edited September 29, 2003 by fishball79 Share this post Link to post Share on other sites
mychew 0 Report post Posted September 29, 2003 oh...forgot to mention...it's powered by AC adapter Share this post Link to post Share on other sites
Rameish 0 Report post Posted September 29, 2003 Hmmm....doesn't sound like my Grado amp :-). Grado Amps were designed to mate with the bright sounding Grado headphones - if anything it has some rolloff in the top end. Very very strange. Share this post Link to post Share on other sites
fishball79 0 Report post Posted September 30, 2003 Maybe still burning in? Share this post Link to post Share on other sites
mychew 0 Report post Posted September 30, 2003 Rameish...yeah...it did provide some roll-off for the high...but not that much..i duno whether i listen wrongly or i made the wrong judgement...that's why i'm waiting for ppl to come in and comments more..anyway..it's just based on my personal preference and taste to test out this amp. Fishball..i'm not sure how long the amp had been burned-in. but i know he did burn in for sometime. just not too sure how long. Edit:he is using wooden box for his grado amp's "housing" Share this post Link to post Share on other sites
huangyong 0 Report post Posted September 30, 2003 (edited) i think it might be due to the wire and solder used. have to check it out. still burn-in?? after burn-in for around 72 hours. i dun like the warm sound so i change the opamp and bring it to mychew, may be this is the reason. AC adapter is 12V 500mA, enough power?? not sure. Btw, i will try it out will a stand alone regulated power supply and see how..... and the power cap, i use electrolytic caps in parallel with ploy cap. to try out new things. but i personnaly don't think it's too bright, may be i have different taste..... and i must say that there is not enough bass to drive my AKG501. still waiting for opinion from you all. Edited September 30, 2003 by huangyong Share this post Link to post Share on other sites
mychew 0 Report post Posted September 30, 2003 not too bright to a certain extend...but it way too high for me i'm not sure what wire and cable usd in your grado amp...but it would be quite enjoying if it got more bass and not so bright that's why that day i say it's quite ok....suitable for ppl new in headfi...if u can make improveent on these yeah...different ppl different taste...what i feel it's bright maybe only soulds a tad bight to u only but i can say the grado amp still have enough room for improvement. i'm waiing for u finished grado amp..i think would be much more better. Share this post Link to post Share on other sites
huangyong 0 Report post Posted September 30, 2003 pics are coming..... tonight.. Share this post Link to post Share on other sites
Rameish 0 Report post Posted September 30, 2003 i think it might be due to the wire and solder used. have to check it out. still burn-in?? after burn-in for around 72 hours. i dun like the warm sound so i change the opamp and bring it to mychew, may be this is the reason. AC adapter is 12V 500mA, enough power?? not sure. Btw, i will try it out will a stand alone regulated power supply and see how..... and the power cap, i use electrolytic caps in parallel with ploy cap. to try out new things. but i personnaly don't think it's too bright, may be i have different taste..... and i must say that there is not enough bass to drive my AKG501. still waiting for opinion from you all. So the op-amp is not the 4556 and you added some poly caps. The Grado RA-1 amp uses 2 x 9-volts hmmm. I don't thing you have a Grado RA-1 clone then. I keep repeating this and am begining to sound like a broken down record player: The main factore that determines the sound in an op-amp based amplifier is the op-amp. Also the solens contribute much of the sound. Huangyong, May I boldly suggest that you return the unit back to stock RA-1 config and add/change one component at a time. Sounds like something when wrong - in terms of sound. Also could we have some pictures? I for one am interested in workmanship. Share this post Link to post Share on other sites