DragonMaster said:
Thanks for that Dragonmaster, I knew I had read about someone with the same observation.....but this is a huge thread now!
I think I'll do the bypass tonight with some 3.0uf's and 50K resistors to see if there is any change.......
DragonMaster said:
Imagine that someone accidentially pushes the pause button while you hold your ear in front of the speaker at max volume....
Yoooow!
I still had AKG AK271 headphones (Borrowed) when I A/Bed the outputs and I was holding the controller.
I think it's important to distinguish between hum and buzz in trying to sort this out.
I define hum as the noise made at 50/60 hz (and harmonics of these) that are associated with raw AC... often this is a grounding or filtering problem in the power supply. Its usually lower in frequency and pretty pure sounding... sort of a 'brrrrrr'.
I define buzz as a middle frequency 'bzzzzzz'. This I associate with SMPS or microprocessor functioning.
I suspect what you are hearing is more of a buzz than a hum... With my PS-1's and fairly low-efficiency speakers, I don't hear any either through my speakers at high volume and didn't before I bypassed the output buffer opamp.
But if I connect a cliplead between the chassis ground of my PS-1 and my amp with the interconnects disconnected, I get a moderate-volume buzz. It doesn't seem to change whether a CD is being played or not, so I am guessing that it is SMPS related. If I connect either the right or left interconnect to the PS-1, then it goes away.
I wonder if anyone who has setup their PS-1 with a linear supply or batteries can try the same thing and see if they get any buzz.
This is one of the reasons I think a linear supply will be the hottest ticket with the modified PS-1's (although my modified SMPS's are sounding pretty good too... I'll do some comparisons with stock PS's this weekend).
Greg in Minneapolis
P.S. I also get some sporatic noise on my FM tuner when I have gear with SMPS's plugged in.
I define hum as the noise made at 50/60 hz (and harmonics of these) that are associated with raw AC... often this is a grounding or filtering problem in the power supply. Its usually lower in frequency and pretty pure sounding... sort of a 'brrrrrr'.
I define buzz as a middle frequency 'bzzzzzz'. This I associate with SMPS or microprocessor functioning.
I suspect what you are hearing is more of a buzz than a hum... With my PS-1's and fairly low-efficiency speakers, I don't hear any either through my speakers at high volume and didn't before I bypassed the output buffer opamp.
But if I connect a cliplead between the chassis ground of my PS-1 and my amp with the interconnects disconnected, I get a moderate-volume buzz. It doesn't seem to change whether a CD is being played or not, so I am guessing that it is SMPS related. If I connect either the right or left interconnect to the PS-1, then it goes away.
I wonder if anyone who has setup their PS-1 with a linear supply or batteries can try the same thing and see if they get any buzz.
This is one of the reasons I think a linear supply will be the hottest ticket with the modified PS-1's (although my modified SMPS's are sounding pretty good too... I'll do some comparisons with stock PS's this weekend).
Greg in Minneapolis
P.S. I also get some sporatic noise on my FM tuner when I have gear with SMPS's plugged in.
I realized I needed to say a couple more things on this...
First, I totally agree that taking out the buffer should help this for you.
Second, if you still have the noise after that, you need to look at grounding and shielding of your other gear and your system.
Greg in Minneapolis
First, I totally agree that taking out the buffer should help this for you.
Second, if you still have the noise after that, you need to look at grounding and shielding of your other gear and your system.
Greg in Minneapolis
Buzzzzz
Hi Guy's,
Greg, yes it is a buzzzz not a hum.
Had a play last night with other players and the portable gear that has tied signal grounds (portable CDP/MP3) don’t make any hum at all...quiet as a mouse!
So I tied the PS1's signal grounds together (wire across the RCA’s) and...... No buzz at all!
Bizarre! If I link up my old HiFi CDP there is no problem with it…and it’s grounds are definitely not tied together!
So I’m going to modify the PS1 with tied signal grounds at the output rather than tie my amp grounds together and see how it goes…..does this seem like an OK solution?
Thanks for all your advice chaps
Lee
Hi Guy's,
Greg, yes it is a buzzzz not a hum.
Had a play last night with other players and the portable gear that has tied signal grounds (portable CDP/MP3) don’t make any hum at all...quiet as a mouse!
So I tied the PS1's signal grounds together (wire across the RCA’s) and...... No buzz at all!
Bizarre! If I link up my old HiFi CDP there is no problem with it…and it’s grounds are definitely not tied together!
So I’m going to modify the PS1 with tied signal grounds at the output rather than tie my amp grounds together and see how it goes…..does this seem like an OK solution?
Thanks for all your advice chaps
Lee
The RCA's (is it an SCPH1002 with L + R RCA connectors ?) are a bit unusual.
If you connect the special TV connector it 'sums' the 2 channels and pumps this through the Left channel RCA only. This is acheived by the tiny 2.5mm jack that powers the external modulator and plugs into the tiny hole next to the RCA .
Anyway I would expect that Micks Mod would fix your problem
If you connect the special TV connector it 'sums' the 2 channels and pumps this through the Left channel RCA only. This is acheived by the tiny 2.5mm jack that powers the external modulator and plugs into the tiny hole next to the RCA .
Anyway I would expect that Micks Mod would fix your problem
jives11 said:
Yes, it is a 1002 with the RCA's.
Thanks for the pointer jives11, I'll connect the adapter up and have a listen this evening to see if that does the trick..but I'll be modding it as per Audio1st version this evening anyway.
New RCA's in the right rear corner with a couple of 3.0uf caps and 100K resistors to ground.
Where would be the best place to pick up ground by the way?
By the DAC?
Cheers
Lee
Lostcause said:
The adaptor is basicaly so you can play sound/music through the TV speaker via UHF (i.e the aerial socket - remember those 🙂 ), so it multiplexes the video and summed stereo sound, fed through the left hand RCA when the adaptor is inserted. All ancient history with the subsequent advent of Comp Video, stereo TV and the dreaded SCART connector, but the PS goes back a few years.
Well I used a 22K resistor to ground as per the photos at
http://www.dogbreath.de/PS1/output/output.html and soldered these to earth at the pads nearby.
At last!
OK guy's, so the mod is done..............eventually! (direct bypass of the output section from DAC to new RCA's through 3.0uf caps and 100K resistors to ground)
So I plugged her in and........Buzzzzzzzzzzzzzz!
Oh sod it I thought (late night/had enough!)
Then I rallied around and went through the usual suspects that did not work when it was stock.
The first thing I did was to put a jumper in from my amps Safety earth to the ground of the RCA's....NO BUZZ!....sounds excellent!
For some bizarre reason this had no effect when stock but now.....completely cured and sounding bang on, except for a bit of midrange grating that I think is down to the Solen fast caps I put in there...not sure
Anyway, I'll leave it running for a few days and see what transpires, as my amp and speakers need a few more hours on 'em anyway.....Maybe put some Obliggatto caps in instead.
Cheers
Lee
OK guy's, so the mod is done..............eventually! (direct bypass of the output section from DAC to new RCA's through 3.0uf caps and 100K resistors to ground)
So I plugged her in and........Buzzzzzzzzzzzzzz!
Oh sod it I thought (late night/had enough!)
Then I rallied around and went through the usual suspects that did not work when it was stock.
The first thing I did was to put a jumper in from my amps Safety earth to the ground of the RCA's....NO BUZZ!....sounds excellent!
For some bizarre reason this had no effect when stock but now.....completely cured and sounding bang on, except for a bit of midrange grating that I think is down to the Solen fast caps I put in there...not sure
Anyway, I'll leave it running for a few days and see what transpires, as my amp and speakers need a few more hours on 'em anyway.....Maybe put some Obliggatto caps in instead.
Cheers
Lee
I don't know if Mick's mod using a Dremel to cut the traces is updated. After I tried it I found that you need to cut all the 3(One for the mono / st switch) audio signal traces going to the RCA plugs and you should put a jumper between both pins on the right channel.
Playstation
Hi all,
I recently joined the Playstation community with a pretty well conserved SCPH-1002. Inspired by Mick F's site and this thread, I also removed all 6 DC blocking capacitors, muting transistors, OPAMP, so I ended up with single DC blocking caps (47uF Elna, bypassed by 1uF polypropilene) and 100k in parallel with the output.
Now to the sound: I didn't get to listen much, but it did not impress me. And that compared to my 100$ DVD-Player Panasonic S-49 (IMHO, a very good sounding component for the money). The Panasonic has clearly superior dynamics and more powerful bass. The PS MIGHT have a somewhat better defined soundstage. Maybe the differences are more subtle, or my ears are lazy.
From the technical point of view: what exactly should make the PS sound good ? The DAC is an old delta-sigma, nothing fancy there AFAIK. My Panasonic has a (much) newer BurrBrown, 24bit/192hKz DAC that seems to clearly outperform the AKM. Or am I wrong there and the PS DAC is really something cool ? Btw, does it use oversampling or not ?
Don't get me wrong, the PS does not sound bad at all- and it's just GREAT for experiments. It's just that, in my case, I don't find it that impressive - but maybe I didn't listen careful enough. Am I missing anything, any mods that I still should do ?
Hi all,
I recently joined the Playstation community with a pretty well conserved SCPH-1002. Inspired by Mick F's site and this thread, I also removed all 6 DC blocking capacitors, muting transistors, OPAMP, so I ended up with single DC blocking caps (47uF Elna, bypassed by 1uF polypropilene) and 100k in parallel with the output.
Now to the sound: I didn't get to listen much, but it did not impress me. And that compared to my 100$ DVD-Player Panasonic S-49 (IMHO, a very good sounding component for the money). The Panasonic has clearly superior dynamics and more powerful bass. The PS MIGHT have a somewhat better defined soundstage. Maybe the differences are more subtle, or my ears are lazy.
From the technical point of view: what exactly should make the PS sound good ? The DAC is an old delta-sigma, nothing fancy there AFAIK. My Panasonic has a (much) newer BurrBrown, 24bit/192hKz DAC that seems to clearly outperform the AKM. Or am I wrong there and the PS DAC is really something cool ? Btw, does it use oversampling or not ?
Don't get me wrong, the PS does not sound bad at all- and it's just GREAT for experiments. It's just that, in my case, I don't find it that impressive - but maybe I didn't listen careful enough. Am I missing anything, any mods that I still should do ?
Take my voice as a minority voice.
I have an unmodified PSX. My only other CD player is a Pioneer DVD player, which is said to be a very good CD player. There's no comparison.
The Pioneer has better bass. But then, the unmodified PSX has bass roll-off. It probably is more dynamic as well. My problem with the Pioneer is that it sounds exactly like all other CD players I have ever heard. I'm talking overall characteristics. I posted something similar once. And that is, it sounds skinny. There's no body. I'm a vinyl junkie and like the "fleshed out" sound of vinyl. So you could say that I dislike CD players, but like the PSX.
I use Altec speakers with 15-inch elements as well as Mårten Designs, so I think I know at least something about bass. I wouldn't call the PSX bass shy.
I couldn't speak about oversampling. All I know is that there's no upsampling. It's a 16-bit converter.
I have an unmodified PSX. My only other CD player is a Pioneer DVD player, which is said to be a very good CD player. There's no comparison.
The Pioneer has better bass. But then, the unmodified PSX has bass roll-off. It probably is more dynamic as well. My problem with the Pioneer is that it sounds exactly like all other CD players I have ever heard. I'm talking overall characteristics. I posted something similar once. And that is, it sounds skinny. There's no body. I'm a vinyl junkie and like the "fleshed out" sound of vinyl. So you could say that I dislike CD players, but like the PSX.
I use Altec speakers with 15-inch elements as well as Mårten Designs, so I think I know at least something about bass. I wouldn't call the PSX bass shy.
I couldn't speak about oversampling. All I know is that there's no upsampling. It's a 16-bit converter.
Thanks for your reply !
Me too I'm looking for more body, but MY PSX also does not seem to have it, or maybe it's the rest of the system (Pioneer A757 + BW602S3) that has a tendency to sound skinny. The Panasonic just sounds more natural to me, more transparent, while the PSX has a slight artificial note. But as I said, I might need more time to form an opinion.
Me too I'm looking for more body, but MY PSX also does not seem to have it, or maybe it's the rest of the system (Pioneer A757 + BW602S3) that has a tendency to sound skinny. The Panasonic just sounds more natural to me, more transparent, while the PSX has a slight artificial note. But as I said, I might need more time to form an opinion.
Indeed, 47uF should be too high. 4.7uF is more like it. No bypass should be used.
As for the body, judging from my system, the amp is a lot more important than the CD player. And my temporary out of commission tube amp does have tremendous bottom end. But I also like the Sonic Impact T amp I currently use.
One more thing. The reason I haven't modified the PSX is because I have only that one. I'm afraid to ruin what I like about it. Once I get another one I will give it a try. So with the amp issue (you don't know how what I have sounds like and vice versa) and me not having heard a modified PSX, these things are very difficult, if not impossible, to describe.
As for the body, judging from my system, the amp is a lot more important than the CD player. And my temporary out of commission tube amp does have tremendous bottom end. But I also like the Sonic Impact T amp I currently use.
One more thing. The reason I haven't modified the PSX is because I have only that one. I'm afraid to ruin what I like about it. Once I get another one I will give it a try. So with the amp issue (you don't know how what I have sounds like and vice versa) and me not having heard a modified PSX, these things are very difficult, if not impossible, to describe.
DragonMaster said:
No, there is a 22k resistor from output to ground (it's only this way it makes sense as a high pass fiter)
Well, people here also have used 100uF, so I don't see why 47uF should be too high ? The bigger the capacity, the lower the cut-off frequency. And why is bypassing bad ? I always thought I can hear smoother highs with a bypass capacitor across electroliytcs. Of course, if you like the "sound print" of an electrolytic, then you don't bypass.
A few thoughts...
Welcome! Good to have you here.
First, I also have a Panasonic DVD Player that I use as a CD Player... model S-47. Mine was professionaly modified for better sound by a noted modifier. Compared to a stock unit, the modified unit retains the dynamics and impact of the stock unit while sounding less 'tizzy' in the treble, more impactive in the bass, and more body to the midrange.
Comparing the S-47 to the PS-1, I find the PS-1 with even minimal mods has a better sense of 'flow' to the music... Enough that it had me starting listen to CDs and buying CD's again.
I listened to it at the following levels, adding the modifications at each level to the ones before...
Stock, I didn't find the PS-1 anything special.
On vibration-absorbing feet with a lead weight on the chassis to the right of the CD door and a home-made VPI Brick (transformer core covered with heatshrink) over the SMPS, it was a little better... At least listenable.
Removing the top of the case, the sense of flow improved along with better mid and bass detailing and dynamics. This was the largest jump in sound quality for the smallest amount of effort.
Damping the case bottom, metal shielding, and CD mechanism with Dynamat, then removing the IC, muting transistors, and using only the last pair of stock coupling caps further increased detailing and dynamics top to bottom. Bass also extended deeper with these mods... I didn't find it lacked anything in the bass compared to the S-47 at this point. This was a very listenable level.
Replacing the stock output coupling caps with 6uf Dynamicaps and the stock output RCA's with better units (older Mogami OFHC) further increased detailing and overall 'naturalness'.
Recently, I've done some parts upgrades in the power supply. I'm not 100% satisfied with the sound after these mods yet. I'm trying to be patient and be sure the parts are fully broken in before I reach conclusions. But so far, dynamics, bass power, and detailing have taken a huge leap forward along with a more neutral frequency balance... I find the PS-1 with the stock SMPS to be a bit recessed in the upper mids and highs, part of it's analog-like sound, but not totally accurate to my ears. This mod at it's best brings a lot of 'jump' and 'startle factor' to the dynamics... But some of the analog-sound listenability has gone, especially during times of the day / week when the system is not at it's best (weekday evenings around here).
I'm not saying this to say that what you heard is wrong... Just that I've heard something different with mine.
One thing you didn't mention was if you did anything for vibration control. If you haven't, try Mick's maple base/innertube thing or find some compliant feet... I use Herbie's from here http://herbiesaudiolab.home.att.net/ along with his CD damping mat.
Another thing that may be affecting your results is component breaking... While the coupling caps I used had been previously used and took less than a week to settle in, I've been listening to my SMPS mods for several weeks and still hearing slight differences over time... I think the breaking is almost done, but not quite there yet.
Finally, I am not familiar with the sound of Elna electrolytic caps as coupling caps and wonder what they contribute here.
I think it is the mechanical and electrical simplicity of the unit... No CD drawer, no display, rudimentary controls (I use a remote with an adapter rather than the cabled controller unit).
I had done an extensive rebuild of a Magnavox CDB-650 back in the middle '90's... Massive multiple power supplies, point-to-point wired DAC and output stage with hi-quality regulators in a separate box vibration-controlled-mounted to the base chassis, many additional regulators in the digitial stages, etc. At one point, I wired in a switch to turn off the display (this had to be done after the CD was playing)... That provided a small, but noticable improvement in smoothness and detailing. Later, I played with removing the CD tray and just setting the CD drive on vibration absorbers in the base chassis... Very large difference, large step forward in sound quality.
On upsampling versus not, I've heard various opinions on whether it is a good thing or not. There's one school that has gone to non-oversampling DACs for best sound... I do want to give that a try sometime. I do know my Njoe Tjoeb improved with the addition of their upsampler... I need to break that out and compare it to the S-47 again and to the PS-1.
If you haven't done some vibration control, that is a must... And even though noone else here espouses this, I say you want to remove the case top for a large lift in sound quality. When you do this, you need to wedge something over the CD door-closed switch to fool the logic... I use a small damper from Herbie's (see link above).
Second, if you have used the Elna's as coupling caps before and had good results, ignore this advice, but if not, try some other caps... Wima polyprops, Dynamicaps, Auricaps, Mundorf, Black Gates, etc. But if you are comfortable keeping the Elna's, give it at least 2 weeks playing music pretty constantly before trying to come to a conclusion... Caps can take a long time to settle down and stop breaking-in.
And I totally agree with you on how great the PS-1 is for experimenting... It's pretty simple and easy to work on and replacement units can be found cheaply, so if you break it, you aren't out much.
Personally, I don't think that 47uf is too big as long as the cap quality is good. It will strongly reduce the low-frequency phase-shift caused by the low-rolloff of the PS-1. And I've heard good results with bypasses, but not always... That has to listened to for whether it is an improvement or not.
Nope... DAC -> cap -> RCA jack with resistor from cap output to ground.
Greg in Minneapolis
bzfcocon said:
Welcome! Good to have you here.
bzfcocon said:
First, I also have a Panasonic DVD Player that I use as a CD Player... model S-47. Mine was professionaly modified for better sound by a noted modifier. Compared to a stock unit, the modified unit retains the dynamics and impact of the stock unit while sounding less 'tizzy' in the treble, more impactive in the bass, and more body to the midrange.
Comparing the S-47 to the PS-1, I find the PS-1 with even minimal mods has a better sense of 'flow' to the music... Enough that it had me starting listen to CDs and buying CD's again.
I listened to it at the following levels, adding the modifications at each level to the ones before...
Stock, I didn't find the PS-1 anything special.
On vibration-absorbing feet with a lead weight on the chassis to the right of the CD door and a home-made VPI Brick (transformer core covered with heatshrink) over the SMPS, it was a little better... At least listenable.
Removing the top of the case, the sense of flow improved along with better mid and bass detailing and dynamics. This was the largest jump in sound quality for the smallest amount of effort.
Damping the case bottom, metal shielding, and CD mechanism with Dynamat, then removing the IC, muting transistors, and using only the last pair of stock coupling caps further increased detailing and dynamics top to bottom. Bass also extended deeper with these mods... I didn't find it lacked anything in the bass compared to the S-47 at this point. This was a very listenable level.
Replacing the stock output coupling caps with 6uf Dynamicaps and the stock output RCA's with better units (older Mogami OFHC) further increased detailing and overall 'naturalness'.
Recently, I've done some parts upgrades in the power supply. I'm not 100% satisfied with the sound after these mods yet. I'm trying to be patient and be sure the parts are fully broken in before I reach conclusions. But so far, dynamics, bass power, and detailing have taken a huge leap forward along with a more neutral frequency balance... I find the PS-1 with the stock SMPS to be a bit recessed in the upper mids and highs, part of it's analog-like sound, but not totally accurate to my ears. This mod at it's best brings a lot of 'jump' and 'startle factor' to the dynamics... But some of the analog-sound listenability has gone, especially during times of the day / week when the system is not at it's best (weekday evenings around here).
I'm not saying this to say that what you heard is wrong... Just that I've heard something different with mine.
One thing you didn't mention was if you did anything for vibration control. If you haven't, try Mick's maple base/innertube thing or find some compliant feet... I use Herbie's from here http://herbiesaudiolab.home.att.net/ along with his CD damping mat.
Another thing that may be affecting your results is component breaking... While the coupling caps I used had been previously used and took less than a week to settle in, I've been listening to my SMPS mods for several weeks and still hearing slight differences over time... I think the breaking is almost done, but not quite there yet.
Finally, I am not familiar with the sound of Elna electrolytic caps as coupling caps and wonder what they contribute here.
bzfcocon said:
I think it is the mechanical and electrical simplicity of the unit... No CD drawer, no display, rudimentary controls (I use a remote with an adapter rather than the cabled controller unit).
I had done an extensive rebuild of a Magnavox CDB-650 back in the middle '90's... Massive multiple power supplies, point-to-point wired DAC and output stage with hi-quality regulators in a separate box vibration-controlled-mounted to the base chassis, many additional regulators in the digitial stages, etc. At one point, I wired in a switch to turn off the display (this had to be done after the CD was playing)... That provided a small, but noticable improvement in smoothness and detailing. Later, I played with removing the CD tray and just setting the CD drive on vibration absorbers in the base chassis... Very large difference, large step forward in sound quality.
On upsampling versus not, I've heard various opinions on whether it is a good thing or not. There's one school that has gone to non-oversampling DACs for best sound... I do want to give that a try sometime. I do know my Njoe Tjoeb improved with the addition of their upsampler... I need to break that out and compare it to the S-47 again and to the PS-1.
bzfcocon said:
If you haven't done some vibration control, that is a must... And even though noone else here espouses this, I say you want to remove the case top for a large lift in sound quality. When you do this, you need to wedge something over the CD door-closed switch to fool the logic... I use a small damper from Herbie's (see link above).
Second, if you have used the Elna's as coupling caps before and had good results, ignore this advice, but if not, try some other caps... Wima polyprops, Dynamicaps, Auricaps, Mundorf, Black Gates, etc. But if you are comfortable keeping the Elna's, give it at least 2 weeks playing music pretty constantly before trying to come to a conclusion... Caps can take a long time to settle down and stop breaking-in.
And I totally agree with you on how great the PS-1 is for experimenting... It's pretty simple and easy to work on and replacement units can be found cheaply, so if you break it, you aren't out much.
DragonMaster said:
phn said:
Personally, I don't think that 47uf is too big as long as the cap quality is good. It will strongly reduce the low-frequency phase-shift caused by the low-rolloff of the PS-1. And I've heard good results with bypasses, but not always... That has to listened to for whether it is an improvement or not.
DragonMaster said:
Nope... DAC -> cap -> RCA jack with resistor from cap output to ground.
Greg in Minneapolis
Thanks for the feedback, Greg !
Yes, I also have dampening - it's sitting on a piece of wood on some elastic foam, but maybe not heavy enough/not enough dampened.
One question: did you remove the whole top of the case, leaving everything uncovered, or just the CD door ?
Cheers
Liviu
Yes, I also have dampening - it's sitting on a piece of wood on some elastic foam, but maybe not heavy enough/not enough dampened.
One question: did you remove the whole top of the case, leaving everything uncovered, or just the CD door ?
Cheers
Liviu