I just swapped out the opamps in my vintage Pioneer PD-M6 CD player. The originals were NJM072B
I replaced them with LME49720. Real easy swap. Two 8 pin DIPs on a single sided PCB. Installed machine pin sockets etc..
Was even able to de-solder the original opamps for re-use if needed.
I didn't think there would be much difference. Oh boy was I wrong!
The distinction and clarity on the mids and highs is incredible. Channel separation seems better. Bass is firmer.
I should have done this a long time ago...
However I am now in a quandary. Most of my CD's have been ripped to .FLAC files. But I don't think I have
a media player that is up to the task. Presently I am playing them out of a Raspberry Pi through HDMI into my TV and then audio out from
my TV into my pre-amp. I don't think they sound nearly as good as my now much improved CD player.
I replaced them with LME49720. Real easy swap. Two 8 pin DIPs on a single sided PCB. Installed machine pin sockets etc..
Was even able to de-solder the original opamps for re-use if needed.
I didn't think there would be much difference. Oh boy was I wrong!
The distinction and clarity on the mids and highs is incredible. Channel separation seems better. Bass is firmer.
I should have done this a long time ago...
However I am now in a quandary. Most of my CD's have been ripped to .FLAC files. But I don't think I have
a media player that is up to the task. Presently I am playing them out of a Raspberry Pi through HDMI into my TV and then audio out from
my TV into my pre-amp. I don't think they sound nearly as good as my now much improved CD player.
I have some but not all. My brothers and I ripped all of our CDs to .flac and co-shared them.
It is like a 250gig plus library
I guess what I am looking for is a high quality media player. I've been looking online and some of them are very expensive.
Need to do some more research.
It is like a 250gig plus library
I guess what I am looking for is a high quality media player. I've been looking online and some of them are very expensive.
Need to do some more research.
So my FLAC player is KODI on a Raspberry Pi that plays out through HDMI and this goes into the TV.
The TV is a fairly recent Samsung. It outputs audio through RCA and this goes through some cables into a Hafler IRIS and DH-200 amp.
Speakers are home built. Tuned port. 12 inch Cerwin Vegas woofers. But ancient ferrofluid midrange and a tweeter that can go out to 50khz
I did a test. I cued up "The Digital Domain - A Demonstration" on the Raspberry Pi (in .flac format) and the genuine CD on the CD player
I could then jump between the inputs on the preamp in real time with the remote.
The results... and of course this is all subjective...
The HDMI through the TV is actually pretty darn good. It has better response on the upper highs.
The CD player with the opamp upgrade has slightly better mid range. Mids are clearer and distinct.
On the DAC "all bits zero" test track the Video input had a small amount of hiss. The CD was almost dead silent.
I am going to attribute the differences to an ancient DAC on the late 80's vintage cd player that is limited on the upper end of things.
Although I wonder if I can tweak the Low pass filter on the CD player.
So I am pretty happy. They are pretty close. I am now thinking that it is time to make a move on Bob Cordell's DH-220C upgrade... and I think I want to upgrade my mid range drivers when I do this.
The TV is a fairly recent Samsung. It outputs audio through RCA and this goes through some cables into a Hafler IRIS and DH-200 amp.
Speakers are home built. Tuned port. 12 inch Cerwin Vegas woofers. But ancient ferrofluid midrange and a tweeter that can go out to 50khz
I did a test. I cued up "The Digital Domain - A Demonstration" on the Raspberry Pi (in .flac format) and the genuine CD on the CD player
I could then jump between the inputs on the preamp in real time with the remote.
The results... and of course this is all subjective...
The HDMI through the TV is actually pretty darn good. It has better response on the upper highs.
The CD player with the opamp upgrade has slightly better mid range. Mids are clearer and distinct.
On the DAC "all bits zero" test track the Video input had a small amount of hiss. The CD was almost dead silent.
I am going to attribute the differences to an ancient DAC on the late 80's vintage cd player that is limited on the upper end of things.
Although I wonder if I can tweak the Low pass filter on the CD player.
So I am pretty happy. They are pretty close. I am now thinking that it is time to make a move on Bob Cordell's DH-220C upgrade... and I think I want to upgrade my mid range drivers when I do this.
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