alvin1118

good idea...maybe should have two separate power supply ?

嘿嘿~~ I have been busy for these few months, struggling with my projects and exams..lifeless!! cant afford to spare any time for my diy hobby! life is so bored! well, i will be released soon!! real soon! ;D To get ready and be prepared to fill my VOID after graduation, here is some diy stuff i specially requested & brought in... MPA2.5 High Precision Power Supply Mono block Power transistor, drive the juice out from ur HD650!! exotic components! Overview YES, this is a DIY project pending to be completed! will do so immediately after my final exam! watch out this thread! cant wait to see it happen!! =================================== Update: Mounted PCB on chassis manage to mount those assembled and tested PCB blocks in the chassis...waiting for the last thing to be in! R-Core transformer, where are you? =================================== Update (26 May 09) sorry for the messy wiring surprisingly very very very clean, almost no notice-able noise when power on!! Even with low impedance earbud ex888lp burning in using STS Digital Burn In CD, any high impedance headphone (>=300ohms) to recommend? Update (31 May 09) weird pairing with ATH-AD700...I believe i really need a dark/warm sounding high impedance headphone.... sh*t

here you go 1. RCA to RCA Guide 2. 3.5mm to RCA Guide

I couldn't make it to the meet tmr, rushing Thesis sorry for any inconvenient caused. See you guys in the next headphone meet

almost missed this thread! Aron please count me in I will be bringing: DAC7010 - ROE Filter Caps, LT1028 @ I/V & LPF The HeadMaster ENOLC / MPA2.5 MonoBlock Headamp Yuin PK2, MOGAMI Recabled Hopefully wont pilot...I'm super ultra packed with the final year project & study these days

yupz, i love her too. both 1st and 2nd albums are nice.

closed..............

nice meet up! wouldn't it be nice to post an announcement of the event b4 the meet?

i noticed there are a few ES7 promotion, saw one selling at amk hub at unbeatable price... strange...

Recable Guide for JVC HA-RX700 Step 1. Remove the earpads, unscrew the three screws. Driver units will then be able to removed Closer look of the driver 2. Remove the stock tiny cable, replace with desired cable. Note that i drilled the right side to optimize recabling for both drivers. Take note of the polarity too. 3. Solder the replaced cable on the PCB terminal. Again, apply good soldering practice 4. The headphone cover is made of ABS plastic, maybe applying some sound isolation material will help improving the sound further? 5. Done.

got myself JVC RX-700 The Headphone Gallery @ Central Shopping Central dont have higher end model, but the RX-700 is good enough!

i cant resist anymore! LOL the design looks like sony line...any one thought so too ?

ah..ok..i was too lazy to read rules NeoMini Digiamp is USB DAC + RA1 Headamp. Whether it's better SQ than AMB Mini3 (in headamp portion) is based on personal preference. Yes, it's Neutrik 6.3mm Jack. You can use 6.3mm to 3.5mm adapter, it's a common accessories for headphile. This kit is meant for diy. It's fun tweaking and modding it. All components and component allocation list are provided in the package, they are to be soldered on the PCB and assembled in the chassis. Face plates holes are pre-drilled (w/ LED holes not shown in the photo), just play electronic lego! Will consider selling assembled set upon request. Workmanship fee will be $35. Again, i encourage ppl to diy instead, wouldn't it be fun to diy your own toy (and save some money to fund for other purchase)?

hm...guys, no discussion in The Classifieds.. PM/msn/sms me k

Dear Headiophile, You are viewing NeoMini DigiAmp. NeoMini DigiAmp is the combination of famous USB DAC, 16bit, 48KHz PCM2702 BurrBown DA Converter, and RA1 headphone amp. High quality Audio grade components, ie. 1% resistors, Panasonic top grade FM Caps, Wima MKS Caps, Genuine Jpn ALPS Volume Pot, and locking type 24Vdc, 2.5A SMPS. Digiamp Assembled set: It looks retro, aint it? something different on your home/office desktop! DIY Kit available too! Details assembly instruction can be found in the following links. PCM2702 chip is pre-soldered, rest assure it's simple, easy to assemble as wiring is minimized. Let's play the electronic LEGO guys! .... and gals(anyone?) Assembly Instruction Guide I Assembly Instruction Guide II Price - Digiamp Assembled Set: S$170 NeoMini Digiamp assembled w/ premium components Custom made casing w/ face plates Locking type 24VDC, 2.5A International SMPS Price - Digiamp DIY Kit Set: S$140NeoMini Digiamp Kit w/ premium components Virtual Gnd Kit Genuine Jpn ALPS 100k Volume Pot Custom made casing w/ face plates Locking type 24VDC, 2.5A International SMPS Thanks for viewing! Have a nice day Sincerely, Alvin Chee Tel: +65 9768 4662 MSN/Email: Alvin1118@hotmail.com

hm...personally prefer active filter

eh, doghead ? the huge volume knob is installed exclusive for my own set... aint it's special ? LOL.. Yup, LPF would give u desired cut off frequency, but then again, the SQ will be 'degraded' if the LPF is constructed using passive components. Will need to trial and error on these suggestion, usually, theory != practical; but theory would lead us to better solution

hehe, let's have some nice photos to start with NeoMini Digiamp = USB DAC + RA1 Headamp Testing & Experimental stage I have bad experience with my "very good" Acer laptop USB I/O to Digiamp (built the first Digiamp year ago), it tends to have very high noise floor, unbearable hissing noise are everywhere as long as it is powered up by stock power supply adapter, thanks to lousy laptop SMPS :\ As such, i have to trial and error to somehow find ways to reduce the noise such that my laptop can be used as main music source. Here's some pics Virtual Ground circuit provides precision, and sufficient power supply to RA1. The USB DAC can be powered by USB Internal Power; but then as mentioned, my Acer laptop power supply is not 'clean' Hence, IC7812 is used to provide +12v for USB DAC +Vin. The intention is to separate the virtual ground power supply with the USB DAC. Added 100ohms at RA1 R&L Channel Output to reduce hissing noise from my Acer Laptop. It serves as attenuator, which would or rather, believed to degrade the sound quality as the extra 100ohms dissipate a fraction of output current from RA1. Happen to met a electronic professional, he suggested to use a 10uf cap on output to gnd; it's one of the solution to reduce noise. I shall try it out when my hand get itchy again : Added extra full bridge rectifier and filter caps, hopping to get 'better' Vdc out from the SMPS comes with Digiamp. Virtual Ground PCB is stacked on the passive components of Digiamp PCB. The hissing noise is significantly reduced, SQ wise is much better than my exception; could be due to the reduce of hissing noise, this 2nd attempt of DIY Digiamp sounded good to me.

i was told that transistor matching aint just measure and match the hfe(beta) value ? found this matching circuit online...

got these PCBs some time back, 2~3months ago i guess I was too busy, finally got time to assemble them ... They are part of NeoMini family, Virtual Ground Kit, Stereo Preamp and Mono Preamp Most Opamps need dual voltage supply, conventional battery only provides +V and 0V. To achieve dual voltage out from a conventional DC source, a virtual ground is needed. What is does is to split the DC voltage into +50%V, 0v, -50%V. if you have a 9v battery passed in a virtual ground circuit, the output will be +4.5v, 0v, -4.5v. NeoMini Stereo Preamp NeoMini Mono Preamp Yupz, they are SMALL, about half of credit card size. Opamp based, can be used as headphone amp. Found some used components in my rack, yeah, just use them for this headamp experimental project :b Finishing....hmm, less than 20mins of work. LOL Why built both stereo and mono preamp? haha, wanted to build a 3-channel headamp, R&L and active ground channel. Source will be my ROE NeoMini USB DAC Pump in Vdc source from wall wart adapter 18v into virtual ground, output +9v, 0v, -9v are connected to +vcc, gnd, -vcc of the PCB; happy singing now Hmm...I miss SMRT... aint they look like a....... train? lol With DIP8 socket, you can rooooooll the opamp on both stereo & active gnd based on your personal preference sounding

K702 for you

see it, the damping cushion on the neodymium magnet driver is removed I'm using diy Cardas 4x24, mid and bass are improved. crystal cable, hm... interesting

curious what is the cable and mod applied on both HD600 & HD650

- Closed -

the y-joint are make up of 3pieces heat shrink, not adhesive type.