jlow

yes that is the pcb, the chassis in bad condition so I throw and keep the boards and CDM9s, got a couple of them Cheap and good and can be used as a player or headphone amp. But the caps has to be changed to better ones to tap the real potential of the CDM9

thanks, a good power supply and a nice chassis is all that is required cool ay? spent less than $500 and you get a nice cd player with a top transport and it comes with a headphone output some more and the audio quality will easily surpass any players in the $1k range, good value jlow

lastest, finally housed the cdm9 with remote control and all in a chassis. power supply and transformer were mounted on the chassis which is 6mm aluminium. I have cut a piece of black arcyllic to replace the top aluminium cover. The cdm9 was mounted on the acryllic and the spin was exceptionally even. I use a soft mount method on light material which was supposedly superior to that of mounting on heavy materials like copper or aluminium. sound wise was great on the 1543 stereo outputs. The typical characteristics of the cdm9 was eminent with its dark backgroud when connected to my EF37A-300B Integrated. but you have to crank the volume higher due to the low output of the 1543 dac stereo outputs through the Signetics 5532 opamps. I'd figured a pair of output trans with 6x gain will be able to fix this. But I just can't find the space in the chassis to accomodate another DAC to take in the i2s output from the cdm9. The TDA1543/NE5532 were already a good treat. Nothing beat the headphone out from the cdm9. The extended vocal details when playing Caiqin was simply captivating. Vocal extension is simply a treat and you got to understand that its coming from a well reputed transport in hifi history. Don't believe? Do a search on the transports that are using the cdm9 and the fans who are still keeping and fixing old transports with this baby on the internet and you will know what I meant. The only disappointment was the slight pop when switching between tracks, otherwise all was worth the trouble. I would think that this is a perfect bed side player for those who are into headphones, without causing nuisance to those bunking in. Ok I am more or less done with this project. Time to move on. Cheers! jlow

Yes this is what makes it beautiful Eject, search, back track, fwd track all from remote The remote is what I desired with all that flexibility built in. jlow Yes thinking real hard about the casing now! Ya WW, I am surprised too. Did not really have time to explore more. I am just going with the normal outputs at the moment. There is a default digital out my job deals with parts and kitset vendors no time to take pics, lately rather occupied.

A bit of update there, recapped the board and replace the stock philips caps . Now its a Oscon galore, with some Muse and FCs. Upon listening, the source is definitely much much cleaner when I first listened to it. I have also changed the volume pot and headphone jack so that I house them nicely when I am done with my chassis jlow

Ok more on this remote control thingy. I managed to get hold of a couple of old philips cdrom that uses the CDM9 and had the remote controller built specifically for it. currently in testing phase, pic for advance info. The whole setup The cdm9 up close 1543 DAC and Signetics 5532 opamp, not bad for a cd rom the PCB It also has a headphone output so its a bonus for those who are into headphone. more updates on my testing on the way.. jlow

Hi all, lately I have been trying to put my junk pile of outdated cdroms to good use. Managed to source for a kitset with remote capable of controlling your old IDE cdrom. The pre-requisite is that you would require a power supply capable of 12vdc 1A and 5vdc 1A. The function of the kitset is such that the remote can control the following: 1. Eject/Load Tray 2. Play/Stop/Tracking 3. Fast Search 4. All actions displayed on LCD display and the remote can be programmed to control player of other brands too... What you have to do is tap the stereo signal output from your cdrom into your preamp or the digital out (some may have) of your favourite USB DAC which can be powered by the same 5vdc supply. I use the LT1085 and should pack enough juice to power the DAC if I want to. I try not to use the PC power supply as I hate the noise coming from the fan. Oh btw I have also invested in an EI core transformer custom wound by Poly. Damn they are ex these days. Ok nothing goes without pics. This is not the end. I have more to share on other cdroms so stay tuned. The naked version, too lazy to build chassis since I am testing some other cdroms. The display, ya I know its facing up side down. The power supply, cost me a lot of $$. But then again a PC tower PS would easily cost $80 and above in any case and they are very noisy in my opinion. The remote, good capabilities. jlow

Ok back to the headphone amp. I took a long time to solder the connecting wire to the iPhone/iPod socket because the pins are so tiny. But it worked. The config is something like this Pin 2 - Gnd Pin 3 - Right Out Pin 4 - Left Out Pin 11 - Gnd, just short to Pin 2 Left and Right out are constant (cannot be controlled by volume pot) at -1 volt rms (believe the usual is -2 volt rms). The amp appeared soft when plugged to iPhone and iPod. When connected to iPod it works fine. When connected to iPhone it shows an error message (something like "You are not plugged in to a supported device.") but works fine. The trick that I found out later is to connect a 68k resistor from pin 21 to ground (short other end of 68K resistor to either Pin 2 or 11) and it should suppress the error message. But if you are too lazy to do that then just live with the error message. This will not blow the iPhone up. I used a 50k volume pot instead of the 100k as recommended. It has some distortion when I crank past 12 o'clock. So out comes the 50k pot and in goes a 100k pot. To make sure that all goes well, I have also bought a pair of input trans from Robert that can step the signal up by 6 times. Let see if this solves the bug for the iPod and iPhone for appearing too soft when plugged in. Adding the input trans is just like adding caps to the iPhone and iPod signal out (if you are familiar with the imod) that did uplift the sonic performance tremendously. But if you are really fussy about what you hear, don't try the unmodded iPhone and iPods, they will disappoint you. The input trans serves it purpose well in this case, and for a change I used trannys instead of caps for this case. Pics Close up, the input trans are housed in an external box so that they can be use for other devices, eg. SS, Chip Amp and others jlow

The internal, not exactly neat but as long as it works...

Nope lately not shifting house so not selling anything to lighten the load. Lately doing this Speaker Upgrade jlow

I have got the EH 6922s and Russian 6N1P and 6H23 (6DJ8) on hand. They all sounded roughly the same. But preferred config is 6H23 on the pre stage and 6N1P on the 2nd stage. As for the rectifier tube using Sovtek 5AR4. Tried 274B the other day but the transformer vibrate a bit, probably due to the higher current draw. Will try that again and listen. tried Vishay 0.47uf coupling caps. Upon listening unsolder them straightaway and threw them away. Now using my favourite Hoveland Musicaps. They are good. Tried Murdorf Gold Oil Caps from Robert and the rest is history. But soldered back the Hovlands as I am using the Murdorfs for other purpose.

Thanks. Basically constructed with parts and tubes which i can lay my hands on at home, other than a few resistor values. Notice that the sound is warmer and easier on listing. Primary guess is the tube rectification. My last amp is SS rectified and I just can't help but feel that it is a tad faster and reponsive on those fast notes. But then again, its for personal use so who cares. But need to find a cover for the naked R-core though... jlow

Someone came to audition the MJ Headphone Amp, liked it so much that he decided to take it home and never want to return it again. So I made another. This time with tube rectification and running on ac heaters. Sounds just the same. Switchable between normal interconnects and a self made iPod cable connect jlow

Wow! Long time...

no probs, thanks bro...

dude, you have any loose c3gs or c3ms pairs. Don't mind keeping a pair

Yes its handmade by myself. But have already stopped making speakers already. Still the same jlow

Quite a bit, it goes as follows: EL34 Push Pull modified with input trans 1626 Single Ended (Made 2 of these and still liked them) 2A3 Single Ended (Sold when shifting house) 6GA4 Single Ended (Jap version of 2A3) 6AH4 Single Ended 5687 Anode preamp (Made 3 of these and always like them) 6SN7 Cathode Follower preamp (Made 2 of these) WE417 WOT preamp TDA1541 DAC Philip CD Pro 2 with CS4397 DAC Enough already, now stopped...

SLT Basement corner shop with a lot of LEDs. Bought years back... I am never into headphone amps but more into building tube gears. Years back some guy I know asked me to build one for him but I never did after hoarding the parts. This is one that I find in the store room which I rebuilt as a past time after I am done with tube stuff. Yep they are the Sprague Orange. I salvaged them from my EL34PP after I switched to Hovlands and subsequently Murdorf. Have yet to do really critical listening. But I tested both the SR60 and SR80. Find the SR80 warmer but more detailed. A tad slow for my prefereence. The SR60 on the other hand is faster and has more dynamics but obviously losing out on details. So the decision. Overall a good buy I would suppose. jlow

Yep using DC Heaters cause don't want to waste too much time bucking hum if it happens. Bought the Grado SR60i this afternoon so got to give the Beyer a miss. Here are the pics. Apologies for lack of standard in the pics as they are taken on the kitchen top using a phone camera. But then if the wife don't mind, I don't think anyone should. jlow

I used 24k for R7. As for hum wise, I dont think there is any but I believe better headphones may tell a better story. Used 6N1P throughout and the current draw too high on the heaters that it pull the voltage below 6 volts. Swopped to 6922 and its much better. Trying out 6DJ8 or 6N23 once I lay my hands on them. Current config is 6n1P on Pre and 6922s on the push pull stage. DC Heaters stablise at 6 volts which is ideal. Almost 30 hours of burning in now, dodgy parts should have been burnt by now. This one looks good. About the BeyerDynamics, what model/price and where to get it?

Dear fellow diyers, I have diyed a Morgan Jones Headphone Amp (Pics coming soon). I have test run it for close to 20 hours without any fault on my cheapo tester headphone. Now I need some recommendation on what would be a good headphone match for this amp if I do 40% vocals/jazz, 40% instruments/orchestra, 20% anything/everything. Any suggestions welcome and appreciated. Many thanks.