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

this is inside the cdrom?

thanks, a good power supply and a nice chassis is all that is required

Wow, great work. Nice!

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

Wow... you're good! Simply excellent!

 

The open top CD player is like a modern turntable COOL!

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

amusingly enough, i set up one on its own with a cheap 20 dollar PSU i had lying around. I wonder if this'll work with a newer CD rom since many have only one button - which i suspect is the biggest issue for me with using a cd rom drive as a player. Also can you go *back* trackwise?

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

Wow, I'm quite impressed! Looks like you can DIY a CDP/DAC/amp all-in-one device on a tight budget. Are you going to make a casing for it in the future?

Yes thinking real hard about the casing now!

Interesting, a CD-ROM drive so old it has I2S. Can tap to send to a better DAC.

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.

would that be the 'digital' pins?

There is a default digital out

Wow, that's very cool!

 

Where did you buy the kit for the CD ROM controller?

my job deals with parts and kitset vendors

where is the cd drive in your second post?

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...

Looks interesting. havent see such a big magnet..

I am looking at getting a pair of speakers, but again I am not in Singapore yet, shifting is tough man.

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.

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.

Very nice Chassis, tube rolling is always much simpler with tubes exposed.

Thats pretty darn nice. Like the wooden sides.

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...

I was the one who bought them, no wonder i find your nick so familiar

no probs, thanks bro...

oops, didnt see this earlier..

 

i actually have just enough for my own projects i.e. 4 pairs etc..

 

if i happen to get my friend to send more over next time, i'll let you know.

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

actually i dont get mine from jac music

 

i have friends in germany so they source for me, the price they get it at is actually a fraction of the online price

 

in singapore so far i only saw aural designs starting to pick up post tube amps, i.e. i saw a c3m pre-amp a couple of weeks ago, but generally not that many people in singapore use them.

 

the other hard to get thing is the socket, which is loctal, and not octal, i get either the NOS siemens one or in my latest shipment cheap ones from china which are a few dollars each

 

another challenging thing about all tube amps is just eliminating hum.. and some solutions can be pricey...

Yes its handmade by myself. But have already stopped making speakers already.

Still the same jlow

Kind of find you familiar jlow, was thinking if you used to own a pair of fostex fe103 in red cabinets.

any non-headphone tube amps to share?

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...

wow this amp is old school.

 

may I ask where you got the case from?

SLT Basement corner shop with a lot of LEDs. Bought years back...

SRPP is "old school" but still sounds good as ever

 

but my main preference now is still SESS (single end single stage)

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.

is that a sprague orange drop cap i see there?

 

i use a pair too

 

how you like the grado with this amp? i once had an sr80 with it but it wasnt quite my cup of tea so i went beyers

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

you're using DC heaters?

 

i've had good aural results with a 6dj8 on pre and a pair of cheap 6n11

 

you can consider beyer dt880 etc. sounds pretty sweet on the mj amp

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've one too except i've dismantled the power supply for use in another project

 

its a good sounding amp if you've weeded out all traces of hum (hey even commercial tube headphone amps hum.. )

 

i used to use mine with beyerdynamics they go pretty well.

 

whats your value of R7?

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.