CD Player's head-out

[PinkFloyd]

Some of these can be VERY good, especially those fitted on earlier models of CDP (circa 1984 - 1990)

Any observations?

[Deleted]

Mike
Many of these were simple dual I.C. circuits on a small PCB with integral headphone jack, with the jack itself often causing intermittent problems. For what they were,they usually didn't sound too bad. The problem with them was that too often they were added as an afterthought and caused degradation of the line output due to the excessive capacitance they added with a fairly long shielded lead virtually in parallel with the main output.
Adding 47 to 100 ohm series resistors to their leads where they picked up the audio often improved matters.
The general advice of many HI-FI magazines of the day was to disconnect them.
Alex

[rickcr42]

Jun 13, 2009 6:27:47 GMT @sandyk said:

Mike
Many of these were simple dual I.C. circuits on a small PCB with integral headphone jack, with the jack itself often causing intermittent problems.

such could be said about a good 75% of consumer grade/DIY4Profit audio devices that use PCB mount Stereo TRS jacks because unlike the original three-circuit/stereo 1/4" phone jacks all of the enclosed pcb mount types have way less strong and far more easily deformed "spring" leafs as the contacts rather than built to take a beating heavy duty positive contact not easily deformed unless you set out to do it intentionally contacts.





skyturtle.com/images/stereo-phone-jack.jpg[/img]

Which one makes YOU more comfortable ?


My take is ALL PCB mounted jacks are a comprimise,the weak link,an intermittant waiting to happen (either due to pcb flex because of the plug in pressure breaking board contact or at the jack itself) thus are THE weak link and especially so when you use the "minis" for portable players which seem to ALWAYS go bad at some point and one not easily fixed since you need to in the case of a stereo phone jack de-solder many pins simultaneously or melt,suck,melt,suck,melt,suck and hope you get them all or it is back to melt,suck,melt........

For what they were,they usually didn't sound too bad. The problem with them was that too often they were added as an afterthought and caused degradation of the line output due to the excessive capacitance they added with a fairly long shielded lead virtually in parallel with the main output.
Adding 47 to 100 ohm series resistors to their leads where they picked up the audio often improved matters.

1-If the "card" used an Op-Amp as the driver,and many did,it is no harder to do an "op-amp rolling" session than it is for any other piece of audio gear (such as your dedicated headphone amps) once you add an I.C. Socket

2-ALL audio gear will have degraded sonics when you run two devices off of a single output simply due to the parallel load situation (something that does not seem to be mentioned much when that "dual output" happens to be a headphone amp "loop through" jacks which place a doubled load on the previous devices output ) unless "steps" are taken to specifically address it and I have yet to see any anywhere in any product or EVEN at the minimum a "kill switch" to break the secondary load for those times it is not needed ( a simple circuit feed "break" in the line)

The general advice of many HI-FI magazines of the day was to disconnect them

Yeah so we have NO CHOICE but to purchase another "box" and a new set of interconnects if we want to listen to headphones,something the manufacturers actually listened to because it increases profit.

Having a headphone output directly from the source has the advantage of eliminating another connection to another box,eliminating another power supply and eliminating "clutter" but is only a plus if the circuits actually work and if so,sound good and I see no reason they can't with a little massaging.

This would mean the "player" could be a self contained "mini system" where,again if done right,one could for instance drive their cans AND with a simple unplug the headphones/plug in the TRS to dual RCA adapter a small desktop speaker driving amplifier making for a tidy multipurpose system with minimal cost-no small thing for some who have either limited resources,limited space,or both.

Remember,if it can drive headphones it can drive a "line" so will actually do quite well as a preamp section/line driver for a power amp while the inverse,a line level preamp,will rarely drive ANY headphones no matter how sensitive due to the impedance mismatch

[Deleted]

Denon DCD1520
Denon Tape DRM44HX
Sony MDP ?...?ES

All source headphone outs are nasty, once you've used a decent HP amp you cannot go back!

....we were also in the habit of disconnecting them.

[PinkFloyd]

Some of the British Hi-Fi mags back in the days used to actually URGE you to listen through the CDP's headout claiming it was "perfect".....

From experience of lots of early Marantz / Philips players I must say that their headouts aren't too bad (the ones with volume controls NOT the fixed output ones) certainly a lot better than, say, the headout of a discman, ipod etc.

Obviously not the "best" there is but surprisingly good for what they are and no problems driving 300R loads either

[Deleted]

Jun 13, 2009 21:38:40 GMT PinkFloyd said:

Some of the British Hi-Fi mags back in the days used to actually URGE you to listen through the CDP's headout claiming it was "perfect".....

From experience of lots of early Marantz / Philips players I must say that their headouts aren't too bad (the ones with volume controls NOT the fixed output ones) certainly a lot better than, say, the headout of a discman, ipod etc.

Obviously not the "best" there is but surprisingly good for what they are and no problems driving 300R loads either

Mike
They had the advantage of using the player's regulated power supply.
Alex

[PinkFloyd]

Jun 13, 2009 21:44:44 GMT @sandyk said:

Jun 13, 2009 21:38:40 GMT PinkFloyd said:

Some of the British Hi-Fi mags back in the days used to actually URGE you to listen through the CDP's headout claiming it was "perfect".....

From experience of lots of early Marantz / Philips players I must say that their headouts aren't too bad (the ones with volume controls NOT the fixed output ones) certainly a lot better than, say, the headout of a discman, ipod etc.

Obviously not the "best" there is but surprisingly good for what they are and no problems driving 300R loads either

Mike
They had the advantage of using the player's regulated power supply.
Alex

Yes,

I know

[rickcr42]

certainly a lot better than, say, the headout of a discman, ipod etc.Obviously not the "best" there is but surprisingly good for what they are and no problems driving 300R loads either

Well they should sound better for higher impedance loads than would a portable player which running on batteries had very limited voltage swing but for low Z cans ?

Not always so black and white until the price differential between the two got to its widest point.Case in point are the "old school" Sony Discman's and the upper end Panasonics,one of which I have and use.

Both have not only more than enough drive for "EZ Load" sensitive cans but can many times not do any better with a very expensive headphone amp hanging off the output and if you DO need more drive ?

Add an external DAC/Amp via the optical digital output,something that went away in PCDP's SOLELY to prevent direct digital CD to Mini-Disc recordings and why even the Mini-Disc players had no digital input in later year models while ALL earlier ones did.


***Edit/Added Section/Addendum***(Reads Continuous)
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Why this route rather than an amp for Hi-Z cans or a Naked Buffer/Unity Gain High Current Out Op-Amp is simple-if you are going to upgrade the output why then would you use the already present "comprimised" analog section (some less so than others as the old school Sony's,Pany's and Denon's prove) as the first stage,the front end to everything that follows ?

WHY hang a $300-$500 "Headphone Amplifier" off a "$0.50" Front End when you can bypass this section entirely via the Optical Output then send the audio along to a combination DAC/Headphone Amp for the same price or not much more ?

This is also the preferred method for "in home" use of a portable where if you give a shit about your audio,and by definition of "audiophile" and the fact that you care enough to haunt an "audio" topic based forum such as the Rock Grotto,then it is also likely somewhere in your system is a dedicated external DAC and if that DAC is a commercial one likely ithas an optical SPDIF input which means a snap to integrate the PCDP with a simple adapter cable.

Going further-Many use their computer platform/computer desk area for the majority of their listening and since in my opinion platback via the computers builtin disc player usually sucks big time the Desktop Portable CD Player option is a step up and especially so if you take the same care as you would with a full sized transport which means powering from a good source of clean DC and transport "external influence" isolation (even IF you use the Anti-Skip buffer which means you are playing from the buffer and NOT from the drive).

Audio Consulting had a ridiculously expensive "Ultimate CD PLayer" on their pages years ago,a real monster that no sane person would pay for BUT-the principals were ALL sound,principals meant to take the simple portable player to "Hi Fi Front End source" status.It consisted of :

1-Clean Power Source-an SLA Battery/Capacitor Bank External PS
2-Total Transport isolation-Wood "bowl" filed with sand which in turn had a wood "lid" upon which the player sat via a three point wood "pillow/bead" system.I would spike the whole deal to the desktop and add a small sandback for some additional top mass (carefully,PCDP lids can tend to squishy and if too much weight it WILL hit the spinning disc ).The system itself is sound due to the size and weight of the player itself and can be done for cheap with a simple craft store wood box or unused jewelry box filled with sand and with the top "trimmed" to fit just inside the box so it floats on the sand.The "footers" can be anything from craft store wood beads to wood blocks to hell,even wood drawer pulls (small ones bubba,small ones).
3-Analog Stage digital ground isolation transformer.Yup,here it is again and is again a thing I fully agree with and ALWAYS use no matter what the source (computer analog out,DAC out,CD/DVD/Blue Ray Player analog Out) because even when I can not hear much A/B difference with or without at least I KNOW there willbe no digital ground contamination in the rest of my system.Keeping out and/or addressing RFI-EMI is to me personally of utmost importance,especially in a mixed signal-analog/digital-system and if your system uses a common ground intput source selector (and most do) this can be a REAL problem,one exasperated by having a digital audio playing device "on" (again as most usually are) but not playing because even though the "hot" of the players signal will be disconnected via the selector switch the players "ground" will not be thus will have an effect on the entire ground bus of the preamplifier/control center.The option of using a switch that selects/deselects both "hot" and "ground" would SEEMINGLY be the fix but in my experience causes as many problems as it solves and with that being the case I would rather KISS (Keep It Simple Stupid) and deal with the ONE known problem than complicate matters,add to the cost and have to deal with MULTIPLE matters.

so if the analog section is fine as is,and many of the old players are even if the dynamics are decreased a bit (low power supply voltages means limited voltage swing) and the output voltage level is lower than your typical digital output (measured in millivolts rather than volts) then the simple bridging transformer option or in a pinch a 1-2 or 1-5 Step Up Transformer option is fine for a desktop based system and if not ?

Optical output (also a DEAD NUTS BLOCK to digital ground noise being an optical feed) to an external DAC/Pre/Amp system.Either way once you have the power supply and isolation parts whipped it comes down to what works for YOU on the analog side but either way once you have the power supply and isolation parts down the small footprint of a portable CD player seems a match made in heaven for a desktop system,one where at a snap of the finger you can unplug and grab the player for some "Music To Go' portable dudty without changing a damn thing.....................other than the batteries for road use

___________________________________________________


As for the original topic,no reason why an EXTERNAL "op amp in a box with power supply" should be any better than an internal card using the already present power supply (DA Analog Section and Line Section) and even moreso if the out of the box version is a CMOY "cloner" from one who can read a project page then who's first thought is not "gee,I can do that" but "Gee,I can SELL that" which unfortuneatly is the modus operandi where far too many products originate while those actually engineered and designed by an actual audio electronics designer are dismissed because the "cloners" are cheaper than the ACTUAL products and yes,having the resources and background that Denon has,as a purveyer of middle up products rather than bottom to middle,I can see where the headphone output should be just fine for average use and damn fine with a bit of stroking on the coupling and bypassing end.


You/we/I also need to consider any attempts to rid your system of "THE WEAK LINK" are GOOD when practical (what is "the weak link ? Interconnect cables of course !) but as with any all-in-one-box vs. all-out-specialized-box-with-dedicated-power-source there are tradeoffs somewhere for both methods,most of which I mentioned above and before..............not that anyone gives a shit what i have to say

[Deleted]

not that anyone gives a shit what i have to say

Rick
If that were so, I wouldn't have read all of what you just wrote.
Alex

[PinkFloyd]

Jun 14, 2009 13:02:33 GMT @sandyk said:

not that anyone gives a shit what i have to say

Rick
If that were so, I wouldn't have read all of what you just wrote.
Alex

X2 ;D

[tg]

I dunno rickster - you usually sound like you know what you are talking about to me - which could be seen to indicate that I do read it - but then I know jack,
so as you say -

not that anyone gives a shit what i have to say