despotic931 said:
What value did you change? Bias or gain?
I had problem with one unit that didn't play any CDs so I adjsuted bias. The only value where every CD was read was at 1.47 V.
The only CD that makes problems starting at track 8 is "A fortnight in France" from Patricia Barber. It's a copy controlled CD which also makes trouble in my other PS1.
Tolu said:
Hehe, I haven't touched either the bias or the gain. I simply tweaked the laser intensity adjustment. I did this while one of the distorted CDs was playing and just tweaked that adjustment until it played the CD fine. However I need to get my multi-meter out and do some actual measurements. And I also need to finish my turntable restoration project, repair my favorite amp, build the speakers I've had my eye on...geez this stuff gets addicting and piles up fast!
What is the exact problem you are having with track 8 on that cd?
-Justin
I found if I turned it max in either direction the CD would simply not play, i would say I only had to turn it about 20-30 degrees clockwise from its original location to get mine to play smoothly. Unfortunately I have yet to get the chance to go to my storage and get my tools, and the projects are piling up! I will get them this week and get you the measurements, hopefully we can get yours running to perfection!
-Justin
-Justin
bought a 'Barely used" scph-1002 off ebay quite cheaply.
this is the first ps1 of 4 that i have that plays all my cd's and cdr's without any hitches. the transport performs equally well in the other ps1's. this is a little strange as i bought 2 NOS transports from the internet that didn't perform half as well.
ah well, who am i to question it? time to sit back with a glass of single malt, and let the notes wash over me.
this is the first ps1 of 4 that i have that plays all my cd's and cdr's without any hitches. the transport performs equally well in the other ps1's. this is a little strange as i bought 2 NOS transports from the internet that didn't perform half as well.
ah well, who am i to question it? time to sit back with a glass of single malt, and let the notes wash over me.
Hi
I replaced at the output stage the cap from WIMA MKS 1µ to Audyn Cap MKP QS 10µ and the resistor from 47k to 1k and added a 1k resistor in series.
Volume and bass are higher than before but the spatiality has decreased and detail information in comparison to the unmodified PS via Multi-AV-out.
What's wrong? Caps are new and out of the box! One reason? Is Multi-AV-out the best option?
I replaced at the output stage the cap from WIMA MKS 1µ to Audyn Cap MKP QS 10µ and the resistor from 47k to 1k and added a 1k resistor in series.
Volume and bass are higher than before but the spatiality has decreased and detail information in comparison to the unmodified PS via Multi-AV-out.
What's wrong? Caps are new and out of the box! One reason? Is Multi-AV-out the best option?
Attachments
Tolu, you're loading down the output of the DAC with 1k, which is very heavy... if you had a dedicated opamp stage, it possibly would take that without problems, but a DAC direct output... I don't like the idea at all...
You may use your 10uF cap very nicely with the same 47k to GND as you had before... this is a clean audio output, there's nothing wrong with setting a very low -3db point... I bet with the 47k and the same cap, you'll have again the good sound you had before!
Remember, for most "weak" (meaning "not-power") opamps (and that includes DAC outputs, sure), a 10k or greater load is very beneficial...
Another possible side effect (and reason for the bad sound) of using that low value resistor to gnd, might be that you're also reducing the input impedance of your power amplifier, as you have that resistor AFTER the cap... it gets probably parallel with your volume pot, reducing impedance greatly... so, it really is a bad idea...
You may use your 10uF cap very nicely with the same 47k to GND as you had before... this is a clean audio output, there's nothing wrong with setting a very low -3db point... I bet with the 47k and the same cap, you'll have again the good sound you had before!
Remember, for most "weak" (meaning "not-power") opamps (and that includes DAC outputs, sure), a 10k or greater load is very beneficial...
Another possible side effect (and reason for the bad sound) of using that low value resistor to gnd, might be that you're also reducing the input impedance of your power amplifier, as you have that resistor AFTER the cap... it gets probably parallel with your volume pot, reducing impedance greatly... so, it really is a bad idea...
joydivision, you're absolutely right. I just wanted to rebuild the A/V-output stage after the enclosed well known circuit but did a mistake. I had to use 100k instead of 1k. What I don't understand is the use of C5 and C6. Are they 120 pF or 120 nF? What is their function? (Sorry but I am a MBA and not an graduate engineer!)
I am currently heating my solder iron and will remove the 1k aginst a 100k! What should I do with C5/6?
I am currently heating my solder iron and will remove the 1k aginst a 100k! What should I do with C5/6?
Attachments
OK, now it is better than before. I have to do some serious listening comparisons between original PS1 Multi-A/V-output (reference) and the modded one. What I can say is that the new mod now plays very fine and detailed with a good but a litte bit narrower stage. I have to give caps a little time to acclimate.
I will further report...
I will further report...
I just modded my PS1 today and I am very impressed. I really appreciate what Mick and the boys have done. Thanks guys!
I used Wima Black Box Audio 3.3uF 5% 400V capacitors, some carbon 22K resistors. The wire I used was nexxtech 18 gauge hook up wire I got from The Source. The solder was silver loaded rosin.
I know nothing of electronics and just mimicked the site for the most part. Does anyone think I should use better wire? I thought it might be a bit crude. Were the Wima caps a good choice? They are much higher voltage than those on the site and are so large they must be placed externally. Would metal oxide or any other kind of resistor be better than the carbon ones? I think the solder is good though and have used it for my cartridge tags.
Anyway, the results were great! Yesterday I just tried the shortening the signal path with the jumper wire mod and that really cleaned up the sound but, like the stock PS1, I found the bass was just a little muted and overall the player needed to hit the 'loudness' button to live up to the claims. Well, I'm very pleased that the full modding did just the trick. I'm really looking forward to the power supply and circuits warming up.
I want to make some more for my dad, brother and some friends so if I can do any tweaking to my approach that would be great. I'll be surfing through this forum in the meantime.
I used Wima Black Box Audio 3.3uF 5% 400V capacitors, some carbon 22K resistors. The wire I used was nexxtech 18 gauge hook up wire I got from The Source. The solder was silver loaded rosin.
I know nothing of electronics and just mimicked the site for the most part. Does anyone think I should use better wire? I thought it might be a bit crude. Were the Wima caps a good choice? They are much higher voltage than those on the site and are so large they must be placed externally. Would metal oxide or any other kind of resistor be better than the carbon ones? I think the solder is good though and have used it for my cartridge tags.
Anyway, the results were great! Yesterday I just tried the shortening the signal path with the jumper wire mod and that really cleaned up the sound but, like the stock PS1, I found the bass was just a little muted and overall the player needed to hit the 'loudness' button to live up to the claims. Well, I'm very pleased that the full modding did just the trick. I'm really looking forward to the power supply and circuits warming up.
I want to make some more for my dad, brother and some friends so if I can do any tweaking to my approach that would be great. I'll be surfing through this forum in the meantime.
Hi
the caps are OK but I would strongly recommend some good metal film resistors!
I am very happy with my choice of 10µ MKP QS and 100k. But it isn't not a final result. Hifi means listen, change, try, listen, listen, modify, listen, compare...
The caps doesn't fit in the original case because they are 1.1" x 1.5". A new case is needed!
My early mod was a 1µ WIMA and 49k. That wasn't good at all. To much highs, no body, no warmth!
I think the original (Multi-AV-) circuit with better parts is the best way to go.
the caps are OK but I would strongly recommend some good metal film resistors!
I am very happy with my choice of 10µ MKP QS and 100k. But it isn't not a final result. Hifi means listen, change, try, listen, listen, modify, listen, compare...
The caps doesn't fit in the original case because they are 1.1" x 1.5". A new case is needed!
My early mod was a 1µ WIMA and 49k. That wasn't good at all. To much highs, no body, no warmth!
I think the original (Multi-AV-) circuit with better parts is the best way to go.
Tolu, some people claim carbon film resistors sound warmer and more musical than metal film resistors... others claim metal film sounds better... I'd say, everyone has to see what he/she likes most...
The only kind of resistor that should always be replaced, are the carbon composite ones, frequently found in old equipment (they're not used anymore, logically). They really do sound bad...
The only kind of resistor that should always be replaced, are the carbon composite ones, frequently found in old equipment (they're not used anymore, logically). They really do sound bad...
Thanks guys, I really appreciate your input. I totally agree with you on experimenting and look forward to doing so. If I was to be critical I think there might be a slight leaness in the upper midrange and maybe a tiny bit in the highs too but I've been distracted by how much the bass and detail improved.
I will try to find some metal film resistors. Are those different from metal oxide?
I don't like the sound of 'OK' for my caps. I thought they would be a good choice as they are 'audio' editions. What other brands are good besides MKP?
Are there instructions anywhere on how to do it this way? or is this what I've already done?
I will try to find some metal film resistors. Are those different from metal oxide?
I don't like the sound of 'OK' for my caps. I thought they would be a good choice as they are 'audio' editions. What other brands are good besides MKP?
Tolu said:
Are there instructions anywhere on how to do it this way? or is this what I've already done?
James,
metal oxide and metal film I think they are the same.
MKP is not a brand, it simply means that the cap is of metallized polyester film type.
Such caps are made by several brands. Most commonly known and one of the best, is WIMA.
It's up to you to find the cap which you like most... I have made the experience that even electrolytic caps can sound good (if you need higher capacitance, it can become very hard to find a MKP or they have enormous size): Panasonic FC.
The MultiAV-out is that connector on the back of the playstation. In the early PS1 model (SCPH 1002) it also delivers the raw audio signal. Look a little bit back in this thread, people were talking about this mod. I think Tolu did this mod, you might try to ask him directly.
metal oxide and metal film I think they are the same.
MKP is not a brand, it simply means that the cap is of metallized polyester film type.
Such caps are made by several brands. Most commonly known and one of the best, is WIMA.
It's up to you to find the cap which you like most... I have made the experience that even electrolytic caps can sound good (if you need higher capacitance, it can become very hard to find a MKP or they have enormous size): Panasonic FC.
The MultiAV-out is that connector on the back of the playstation. In the early PS1 model (SCPH 1002) it also delivers the raw audio signal. Look a little bit back in this thread, people were talking about this mod. I think Tolu did this mod, you might try to ask him directly.
Hi James
just look at post #2050 and you will understand. That's what I did!
I did some investigations about your caps and they seem to be very good! So, relax on that issue. Like Joydivision said, simple carbon resistors are grainy and have often high distortion. Try some others. I think there is a difference between metal oxyd and metal film.
Another reason for choosing that values: look at the data sheet of the AKM 4309!!!
just look at post #2050 and you will understand. That's what I did!
I did some investigations about your caps and they seem to be very good! So, relax on that issue. Like Joydivision said, simple carbon resistors are grainy and have often high distortion. Try some others. I think there is a difference between metal oxyd and metal film.
Another reason for choosing that values: look at the data sheet of the AKM 4309!!!
AK4310VM & AK4309AKM comparision
i have two ps1: 1001 and 1002 models.
the mainboards are pretty different, and 1001 uses AK4310VM.
is there anyone who know about the differences between these two models, actually these two DACs.
i attached some pics for both models. left one is 1001, the other 1002.
thanks for your help...
i have two ps1: 1001 and 1002 models.
the mainboards are pretty different, and 1001 uses AK4310VM.
is there anyone who know about the differences between these two models, actually these two DACs.
i attached some pics for both models. left one is 1001, the other 1002.
thanks for your help...
AK4310VM & AK4309AKM comparision
i have two ps1s: 1001 and 1002 models.
the mainboards are pretty different, and 1001 uses AK4310VM.
is there anyone who know about the differences between these two models, especially these two DACs. i wonder which one performs better. (i did a RCA sound stage mod to 1001, 1002 is original)
please have a look at the URL for the comparision pics of two models.
thanks for your help...
http://b1r.net/ps1/00.jpg
i have two ps1s: 1001 and 1002 models.
the mainboards are pretty different, and 1001 uses AK4310VM.
is there anyone who know about the differences between these two models, especially these two DACs. i wonder which one performs better. (i did a RCA sound stage mod to 1001, 1002 is original)
please have a look at the URL for the comparision pics of two models.
thanks for your help...
http://b1r.net/ps1/00.jpg