I was using this as a journal for my own recollections but after thought I would share it with any one willing to read it.
These are my Mission Cyrus 2 exploits. It may be of interest to some and some may have heard it all before. Here goes.
I am not a tech or anything but I can solder and have a vague understanding of electronics and can read info off the web. I do have original Cyrus schematics. I WILL NOT attempt anything I do not understand. Just a warning for people who may be tempted to “have a go”!
It all started when I was trying to set up my turntable. No matter what I seemed to do to my cartridge, azimuth, bias etc I was getting a slightly louder output through the left channel of the amp.
I had considered for a while about fitting a blue Alps pot as I had fitted one before to an old Cambridge P50 amp with great result.
The pot arrived and was duly fitted, great difference. Balance was more centralised and the soundstage and whole music just gelled better. Although the old one did not crackle or anything it was obviously tired.
As usual the bug bit and I thought I would update the old original electrolytics and a couple of resistors to put in place where the old balance pot would have sat.
I thought I would do things in a sequence just to see what difference, if any, was made.
The first things were the resistors (51K 0.25W TAKMAN Carbon Film Resistor)
to the empty balance space. I didn’t know if I needed to do this but thought it best to keep loads etc the same.
Next were the pre-amp psu caps. After some deliberation (others may be tried in the future) these were replaced with 470uF 63V Audio Note Standard Electrolytic Capacitor for the 2 large caps and 22uF 63V Audio Note Kaisei POLAR Electrolytic Capacitor for the 4 smaller smoothing/ decoupling caps. Wow what a difference. The whole musical image really widened and deepened outside the loudspeakers. The sound was cleaner treble, a nice deep bass and a nice natural organic timbre on the whole. Fantastic as these parts are not that cheap and I was working on a very tight budget.
Next were the 4 decoupling caps on the rails with 100uF 50V Elna Silmic II Electrolytic Capacitor.
Another fantastic improvement as said before but even more. Goodness I had never heard the amp sound like this. For an outlay of around £25 just for the psu it was well worth it.
Next came all the 6 old smaller electrolytics with 22uF 25V Elna Silmic II Electrolytic Capacitor.
Now this was a shock. All the work done above seemed to shrink in to a smaller soundstage. Very disappointing. The plus side the sound was cleaner with a very natural dark sound but saying that it also sounded slightly smeared in so much the noise inherent on old vinyl groove was missing. Surely if this was not there then everything in that frequency range was also not there explaining the darker sound. I’d read it takes time for things to ‘burn in’ and settle down but this was a bit odd seen as I had such massive improvements with the psu/ decoupling components.
Ah well, I gave it a few days and as the pre section is always on in the Cyrus and the selection set to phono, playing lps gradually the sound began to open up again. Not as wide as before but I thought I’d carry on with the non-polar lytics anyway.
These were all replaced with 1.1uF and 2.2uF 50V Nichicon (Muse) ES type.
Also the 2 big feedbacks with 470uF 16V Nichicon ES type.
This was another subtle improvement. Slightly better soundstage, all instruments and voices firmly set in place and sounding very natural. There was still a slight smear as before but I thought I would let things settle down for a while to see what happened.
Well after a week or so the sound opened up slightly but it still was lacking.
I have started experimenting with bypassing the non polar lytics with smaller film caps 0.022uF, 0.047uF to 0.1 uF from Kemet, Wima and Epcos.
I had a nice slight clean up in sound bypassing the 4 100uF 50V Elna Silmic II caps.
I am still playing with the other ones and will let you know the results.
Test record was John Martyn- Inside Out (ILPS 9253, pink rim)
The thing I would like to know now is if anyone has replaced the phono cable inside the amp with Cardas cable? and also is totally bypassing the mm/mc switch by connecting from phono socket to pre psb likely to cause a problem?
Thanks for reading and I am looking forward to your comments.
These are my Mission Cyrus 2 exploits. It may be of interest to some and some may have heard it all before. Here goes.
I am not a tech or anything but I can solder and have a vague understanding of electronics and can read info off the web. I do have original Cyrus schematics. I WILL NOT attempt anything I do not understand. Just a warning for people who may be tempted to “have a go”!
It all started when I was trying to set up my turntable. No matter what I seemed to do to my cartridge, azimuth, bias etc I was getting a slightly louder output through the left channel of the amp.
I had considered for a while about fitting a blue Alps pot as I had fitted one before to an old Cambridge P50 amp with great result.
The pot arrived and was duly fitted, great difference. Balance was more centralised and the soundstage and whole music just gelled better. Although the old one did not crackle or anything it was obviously tired.
As usual the bug bit and I thought I would update the old original electrolytics and a couple of resistors to put in place where the old balance pot would have sat.
I thought I would do things in a sequence just to see what difference, if any, was made.
The first things were the resistors (51K 0.25W TAKMAN Carbon Film Resistor)
to the empty balance space. I didn’t know if I needed to do this but thought it best to keep loads etc the same.
Next were the pre-amp psu caps. After some deliberation (others may be tried in the future) these were replaced with 470uF 63V Audio Note Standard Electrolytic Capacitor for the 2 large caps and 22uF 63V Audio Note Kaisei POLAR Electrolytic Capacitor for the 4 smaller smoothing/ decoupling caps. Wow what a difference. The whole musical image really widened and deepened outside the loudspeakers. The sound was cleaner treble, a nice deep bass and a nice natural organic timbre on the whole. Fantastic as these parts are not that cheap and I was working on a very tight budget.
Next were the 4 decoupling caps on the rails with 100uF 50V Elna Silmic II Electrolytic Capacitor.
Another fantastic improvement as said before but even more. Goodness I had never heard the amp sound like this. For an outlay of around £25 just for the psu it was well worth it.
Next came all the 6 old smaller electrolytics with 22uF 25V Elna Silmic II Electrolytic Capacitor.
Now this was a shock. All the work done above seemed to shrink in to a smaller soundstage. Very disappointing. The plus side the sound was cleaner with a very natural dark sound but saying that it also sounded slightly smeared in so much the noise inherent on old vinyl groove was missing. Surely if this was not there then everything in that frequency range was also not there explaining the darker sound. I’d read it takes time for things to ‘burn in’ and settle down but this was a bit odd seen as I had such massive improvements with the psu/ decoupling components.
Ah well, I gave it a few days and as the pre section is always on in the Cyrus and the selection set to phono, playing lps gradually the sound began to open up again. Not as wide as before but I thought I’d carry on with the non-polar lytics anyway.
These were all replaced with 1.1uF and 2.2uF 50V Nichicon (Muse) ES type.
Also the 2 big feedbacks with 470uF 16V Nichicon ES type.
This was another subtle improvement. Slightly better soundstage, all instruments and voices firmly set in place and sounding very natural. There was still a slight smear as before but I thought I would let things settle down for a while to see what happened.
Well after a week or so the sound opened up slightly but it still was lacking.
I have started experimenting with bypassing the non polar lytics with smaller film caps 0.022uF, 0.047uF to 0.1 uF from Kemet, Wima and Epcos.
I had a nice slight clean up in sound bypassing the 4 100uF 50V Elna Silmic II caps.
I am still playing with the other ones and will let you know the results.
Test record was John Martyn- Inside Out (ILPS 9253, pink rim)
The thing I would like to know now is if anyone has replaced the phono cable inside the amp with Cardas cable? and also is totally bypassing the mm/mc switch by connecting from phono socket to pre psb likely to cause a problem?
Thanks for reading and I am looking forward to your comments.
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Try paragraphing the text of your post and using formal sentence structure. It's very hard to read in one block and lacks that vital element of clear communication. Then we might understand your motivations a little better and see whether there is basis for total recapping or perhaps it's a shotgun approach to refurbishing, where simply more expensive brand components are used to replace anything that can be.
It may satisfy a desire to engage and do something to improve our audio gear but do it wisely. Read more than the chatter of folk who've done similar and enthuse about what brand X caps did for their sound quality. Some film capacitors (for example, Styroflex polystyrene film/foil types fitted in early Cyrus models) are not improved on by replacing with modern types. That's likely a backward step.
Carbon film resistors are used because they are the cheapest type but not better than metal film types, regardless of parroted claims about the sound quality of carbon resistors that we read on the internet. Much of the chatter is not only subjective but purely personal impressions which I have come to realise, can change with the hour, day and mood of listeners. Facts are rare when inexperienced folk discuss recaps.
'Good that the potentiometer replacement worked out well for you, though. Mechanical devices like switches, buttons, relays and pots are always a problem because they wear and/or break after some length of time and the old favourites are really old now - perhaps beyond economical repair.
It may satisfy a desire to engage and do something to improve our audio gear but do it wisely. Read more than the chatter of folk who've done similar and enthuse about what brand X caps did for their sound quality. Some film capacitors (for example, Styroflex polystyrene film/foil types fitted in early Cyrus models) are not improved on by replacing with modern types. That's likely a backward step.
Carbon film resistors are used because they are the cheapest type but not better than metal film types, regardless of parroted claims about the sound quality of carbon resistors that we read on the internet. Much of the chatter is not only subjective but purely personal impressions which I have come to realise, can change with the hour, day and mood of listeners. Facts are rare when inexperienced folk discuss recaps.
'Good that the potentiometer replacement worked out well for you, though. Mechanical devices like switches, buttons, relays and pots are always a problem because they wear and/or break after some length of time and the old favourites are really old now - perhaps beyond economical repair.
Thanks Ian for the constructive critique. I was worried there was a letter count in place so I have structured the layout to a better form as suggested..
I think when people start to get into doing diy hifi upgrades it is easy to fall into a trap of getting sucked into peoples views on forums on the internet and product hype.
People could have a massive philosophical/ psychological argument about esoteric parts.
Of how one can be easily led into a path of buying one particular resistor or capacitor over another.
Due to my lack of money and my little electronic knowledge I ended up going in a direction that maybe perceived as wrong. I was not going to refurb the amp to this extent but it ended up seeing how far I could get sound-wise on a small budget.
I bought most of the components from Hifi Collective as it has a wide selection. Now this is not their fault but this is where the trouble begins as now I had to choose between a carbon film or metal film resistor.
I did not even need them in the circuit I guess but I chose the carbon over metal as it has a good sales pitch and I probably read somewhere they sound better which is ludicrous seen as the Cyrus is full of metal film resistors. It was also cheaper which is even more ludicrous seen as I decided to put more impetus on the capacitors and spent a silly amount of money on the AudioNote caps.
I had recently bought 270 various size caps from china for less than £6 and I should have tried using them before the esoteric route just to see what happened to the sound.
I was worried that because they were so cheap either they were going to sound rubbish and was not worth all the hard work of swapping them over or my beloved Cyrus would disappear in smoke.
If money was no object I would give it a go just to see what occurred. I would also like go in the other direction and put really nice parts in it. I know the design of the amp probably does not quantify doing that but it would be nice to see what actual difference it would make.
To summarise, the whole point of me doing this was to experiment. I have altered the sound of the amp. It does sound nice but is different than original sound. This is where the problem lies because I never heard the amplifier new, I never really knew what it sounded like in the first place. This is how if you chase the new improved original 'used sound' you end up buying lots of parts from esoteric shops.
I still feel you can have fun doing this though which is part of the hobby. Not for all though i guess.
I think when people start to get into doing diy hifi upgrades it is easy to fall into a trap of getting sucked into peoples views on forums on the internet and product hype.
People could have a massive philosophical/ psychological argument about esoteric parts.
Of how one can be easily led into a path of buying one particular resistor or capacitor over another.
Due to my lack of money and my little electronic knowledge I ended up going in a direction that maybe perceived as wrong. I was not going to refurb the amp to this extent but it ended up seeing how far I could get sound-wise on a small budget.
I bought most of the components from Hifi Collective as it has a wide selection. Now this is not their fault but this is where the trouble begins as now I had to choose between a carbon film or metal film resistor.
I did not even need them in the circuit I guess but I chose the carbon over metal as it has a good sales pitch and I probably read somewhere they sound better which is ludicrous seen as the Cyrus is full of metal film resistors. It was also cheaper which is even more ludicrous seen as I decided to put more impetus on the capacitors and spent a silly amount of money on the AudioNote caps.
I had recently bought 270 various size caps from china for less than £6 and I should have tried using them before the esoteric route just to see what happened to the sound.
I was worried that because they were so cheap either they were going to sound rubbish and was not worth all the hard work of swapping them over or my beloved Cyrus would disappear in smoke.
If money was no object I would give it a go just to see what occurred. I would also like go in the other direction and put really nice parts in it. I know the design of the amp probably does not quantify doing that but it would be nice to see what actual difference it would make.
To summarise, the whole point of me doing this was to experiment. I have altered the sound of the amp. It does sound nice but is different than original sound. This is where the problem lies because I never heard the amplifier new, I never really knew what it sounded like in the first place. This is how if you chase the new improved original 'used sound' you end up buying lots of parts from esoteric shops.
I still feel you can have fun doing this though which is part of the hobby. Not for all though i guess.
mrbluesurf,
you approached and carried out the task in an exemplary way. Metal film resistors exhibit high frequency distortion.
you approached and carried out the task in an exemplary way. Metal film resistors exhibit high frequency distortion.
N101, you might have said that a generalisation like that is not the real picture regarding resistors that are available to DIYs at affordable prices. As mrbluesurf has experienced, there are some crazy overspecced components out there at crazy prices because there are only tiny markets and few uses or budgets for them. Some recappers find rare and expensive qualities alone to be attractive but the components are usually no better, other than being new electrolytic capacitors for example, than common parts in the application. There are few locations where exotics make any real and verifiable improvements in power amplifiers.
FYI, distortion differences between common resistor types only show up in audio at voltage differences above about 10V and MF is the lowest, compared to any carbon type. Audio Power Amplifier design, 6th edition, D.Self - The Basics of distortion.
https://www.eetimes.com/document.asp?doc_id=1272283#
FYI, distortion differences between common resistor types only show up in audio at voltage differences above about 10V and MF is the lowest, compared to any carbon type. Audio Power Amplifier design, 6th edition, D.Self - The Basics of distortion.
https://www.eetimes.com/document.asp?doc_id=1272283#
The distortion is due to high material (mass, charge) density and is even more critical in the case of capacitors. It has general validity. I was not advocating exotics, but rather cheap carbon-based resistors, tacitly anyway.
Metal film resistors are about the most linear components in existence, nothing else in the circuit matches them for performance, so if you don't like them, there's nothing that will satisfy you!
Some guy's on our local diy forum states that carbon film resistors has a more laid back sound, I can not recall if it is in the feedback circuit, or wherever,but I have no experience with such claims.
Just out of interest I did a search for 'best resistors in signal path' as I thought to change the two directly after the Alps pot I found this post
Signal path Resistor Quality
Goodness me.... bicker bicker. LOL
Has anybody got an answer to losing the MM/ MC switch on the phono pre and wiring directly from phono sockets to pre pcb on the Cyrus 2?
Or any other constructive suggestions barr diode replacement.
Please no squabbling.
Signal path Resistor Quality
Goodness me.... bicker bicker. LOL
Has anybody got an answer to losing the MM/ MC switch on the phono pre and wiring directly from phono sockets to pre pcb on the Cyrus 2?
Or any other constructive suggestions barr diode replacement.
Please no squabbling.
Why remove it? If the switch contacts are still firm and clean, there won't be any improvement and you lose the opportunity to try vinyl by either type of cartridge for yourself some day. Otherwise, all the phono circuits will be switched out by the source selector switch anyway. Download and study the service manual schematics before going in with the knife.
Keep in mind that the next guy you sell it to when your interest shifts to another project, will see your modifications as a minus. Everyone wants an unspoiled model to play with and our resolve to keep things can change radically when the opportunity to do something more interesting arises.
Keep in mind that the next guy you sell it to when your interest shifts to another project, will see your modifications as a minus. Everyone wants an unspoiled model to play with and our resolve to keep things can change radically when the opportunity to do something more interesting arises.
Sorry. i didn't explain very well.
I mainly use vinyl and what I meant was to connect the phono sockets directly to the pcb with the phono cable then totally skipping out the switch.
If you are not familiar with the Cyrus there is a cable that connects (inside the unit ) from phono socket to selector switch mm/mc then to pcb.
The switch is ok but I was thinking one less connection. As I did consider going
direct from cartridge to phono in one length and then the mod above. Any Thoughts?
I mainly use vinyl and what I meant was to connect the phono sockets directly to the pcb with the phono cable then totally skipping out the switch.
If you are not familiar with the Cyrus there is a cable that connects (inside the unit ) from phono socket to selector switch mm/mc then to pcb.
The switch is ok but I was thinking one less connection. As I did consider going
direct from cartridge to phono in one length and then the mod above. Any Thoughts?
The phono inputs already connect directly to either MC or MM input gain stages on the PCB. The selector switch then alters the coupling of either to the following RIAA stage. Test for noise if you like, by simply placing shorts on the pcb between the relevant leads to the switch that connect in whatever position (you don't specify your cartridge type) you require . If you can't hear (or better, measure with even your DMM at the output stage) any noise reduction, lose them. Again, check the service manual details. Start with the block diagram of the circuit which shows electrically, where the input and interstage connections are made.
Cyrus 2 - Manual - Stereo Integrated Amplifier - HiFi Engine (free download after registration)
Cyrus 2 - Manual - Stereo Integrated Amplifier - HiFi Engine (free download after registration)
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