Sonusthree said:
the work you have done on your cyrus looks well smart did you wire the phonos to the pot and bypass the strip lead
thanks for your help looks well nice
Sonusthree said:
hi thanks for the pic those are the ones have you seen martins cyrus it look very good
hi martin have you compered this amp to a standard cyrus 2 i will copy what you have done makes it easy for my thanks again
Hello What's Gan On,
The RCA sockets are wired directly to the switch just like the original ribbon but on the underside. Beware of lifting the small pads.
In my case the ALPS blue gave the same effects that you have noticed. It just lets more detail through.
Hifi collective kind of have the shaft couplers:
http://www.hificollective.co.uk/catalog/product_info.php?cPath=61_127&products_id=713
You'll see what I mean if you try to 'visit this product's web page'. It takes you to a page of pots and no coupler. This may have been where I got mine from some time ago. They have it listed in one of their kits so they may have some stock if you phone?
I have one spare but 2 of the 4 screws are missing. It would still hold very well 'til you can find another one. P.M. me if you need it and I'll pop it in the post right away.
I haven't yet compared it side by side to an original Cyrus2. The pot was by far the biggest improvement. I don't really think it would be fair to do so given the age of the amps and the different effects that has had on parts.
E.G. Some have worn pots (some worse than others), some have temperamental switches, some phono stages oscillate because of ageing caps....... you get the idea.
Would be interesting though.
Cheers,
Martin
(Sonusthree)
P.S. Don't wire the speaker terminals backwards like me. I hang my head in shame.
The RCA sockets are wired directly to the switch just like the original ribbon but on the underside. Beware of lifting the small pads.
In my case the ALPS blue gave the same effects that you have noticed. It just lets more detail through.
Hifi collective kind of have the shaft couplers:
http://www.hificollective.co.uk/catalog/product_info.php?cPath=61_127&products_id=713
You'll see what I mean if you try to 'visit this product's web page'. It takes you to a page of pots and no coupler. This may have been where I got mine from some time ago. They have it listed in one of their kits so they may have some stock if you phone?
I have one spare but 2 of the 4 screws are missing. It would still hold very well 'til you can find another one. P.M. me if you need it and I'll pop it in the post right away.
I haven't yet compared it side by side to an original Cyrus2. The pot was by far the biggest improvement. I don't really think it would be fair to do so given the age of the amps and the different effects that has had on parts.
E.G. Some have worn pots (some worse than others), some have temperamental switches, some phono stages oscillate because of ageing caps....... you get the idea.
Would be interesting though.
Cheers,
Martin
(Sonusthree)
P.S. Don't wire the speaker terminals backwards like me. I hang my head in shame.
hi martin i have sent you my name and address, thanks for the offer martin. i want to buy a psx would get one for around £50 or do they go for much more. i find my amp is forward sounding does the psx make it more warmer on the vocal,s can you remember what improvements it makes. does it make a worth while improvement ,as i removed the the phono stage power supply and i gained a little bass ,were as be fore it was bass shy
thanks for all your help
kieran
thanks for all your help
kieran
whats gan on said:
Hi Kieran,
I haven't received your email yet so I will send one to your MSN address directly so that you can reply. Check your inbox soon!!
I reckon that PSX go for around £100 - £120 at the moment on Ebay. Prices on early Cyrus stuff has risen alot over the last 12 months. Didn't even fall at Christmas like it usually does. I've seen some CRAZY prices even for Cyrus 1's.
An Isoplat is at £47 + P&P at the moment on the 'Bay!!
The Cyrus amps were never really supposed to be for loads under 8 Ohms. Your Tannoys are 6 Ohms and a bigger supply would help with the extra current draw. The PSX puts out +/- 40V. The PSX transformer is 500VA with 60,000uF Slit foil caps.
For more details of the PSX,with pics, see this thread: http://www.diyaudio.com/forums/showthread.php?postid=1108437#post1108437
In my opinion, the PSX does not make a huge difference at normal listening levels. The bass does have more 'body' to it but it doesn't change the tonal balance of the amp in my system.
Imagine the difference between a Cyrus One and a Two. It just makes it a bit more like a Cyrus 'Two and a Half'. 😀
As we have discussed before, I have the same forward sound that you are experiencing. We have very similar speakers.
I don't want to wonder too far off topic but I have had to build an active circuit to gradually boost frequencies from ~120Hz down. It's still being tweaked on breadboard but sounds remarkably good. Although, it must be said that some detail is lost.
It's a compromise that I'm hoping to improve upon with experimentation.
I will eventually go semi-active with a Cyrus One on the highs.😀
Regards,
Martin.
hi martin what you discribe the sound when adding a psx is what i found when disconnecting the phono stage more bass not loads more but a more fuller sound have you a pic of the psx with the lid off .i could copy it and make my own power supply with the help of my mate who is great at building a power supply. what i would like to do is try and make the recording have more depth like the recording studio was if it were in a bigger room behind the speakers
have you fitted a mains filter to your amp i was thinking of trying to tone the amp down a touch, as my mate brought his class a musicalfidelity amp and it was really nice wide sound stage laid back but i really thought the cyrus was as good but forward and a touch hard, but up there with the fidelity which cost hundred's more
sorry i do not understand what you have done to your speakers you lost me there
have you fitted a mains filter to your amp i was thinking of trying to tone the amp down a touch, as my mate brought his class a musicalfidelity amp and it was really nice wide sound stage laid back but i really thought the cyrus was as good but forward and a touch hard, but up there with the fidelity which cost hundred's more
sorry i do not understand what you have done to your speakers you lost me there
I have already posted pics there😉Sonusthree said:
If you are going to make your own PSX then you NEED to read that thread carefully.
I have more high resolution photos available.
I'm not sure which bit you don't understand? I will try to clear up any misunderstandings.
1: I have made a kind of "Bass Boost" device between the CD and amp for a more balanced sound with ....... more bass. Imagine a kind of simple preamp that amplifies the bass more than the treble and you'll get the idea.
2: I intend to remove the crossover from my speakers and use separate Cyrus amps wired directly to the drivers:
Cyrus One for the treble.
Cyrus Two with PSX for the Bass/Mid.
I would then have to separate the different frequencies BEFORE the amplifiers by using an 'ACTIVE crossover'.
A quick search on these forums will give more details on this.
The real advantage here is that the amplifiers effectively have a better control of the speaker's movement.
Another advantage for us is that it may be easier to address the forward nature of our systems by filtering out the offending frequencies.
Yes, I do use a mains filter on my sytem. Try searching this site.
It helps me but everybody's mains is different:
Positive: More subtle detail and a quieter background.
Negative: Slightly reduced dynamics.
P.S. I have just posted the coupler and it should arrive on Tuesday.
Regards,
Martin. 🙂
hi martin thank you for the part and posting it for tuesday. i fully understand what you have done now the last post cleared up nicely,i would like to see this device it sounds interesting. i had a look at your pics of psx it looks like a regulated power supply thanks again
kind regards
kieran
kind regards
kieran
Hi Kieran,
The PSX supply for the Cyrus Two is NOT regulated. It is basically a very simple design but with a huge transformer and lots of quality capacitance.
The left hand side of the PSX board is a regulated +/-18V supply intended for the Mission (Cyrus) PCMII CD player.
You could probably omit this section for your needs.
I would be happy to answer any further questions in this thread:Cyrus PSX Thread
Regards,
Martin.
The PSX supply for the Cyrus Two is NOT regulated. It is basically a very simple design but with a huge transformer and lots of quality capacitance.
The left hand side of the PSX board is a regulated +/-18V supply intended for the Mission (Cyrus) PCMII CD player.
You could probably omit this section for your needs.
I would be happy to answer any further questions in this thread:Cyrus PSX Thread
Regards,
Martin.
Attachments
Hi,
have a think about the Cyrus One & Two and try to imagine what the designer was trying to achieve.
The One had a small transformer that could by conventional design support an output of about 40W/channel.
The Two has the same smoothing capacitors and a bigger transformer that should be able to support 80W/channel. They spent the time and money developing and releasing this product and to me it seems obvious that they believed there was some performance advantage in using a transformer that is over-rated to about 160%. (VA>=1.5* maximum output power).
Users report that the PSX adds a little bit more and yet the transformer should be way over the top at about 300% over-size.
This leads me to suggest that the main performance enhancing characteristic is not the very large transformer, which can only help, but much more to do with the increase in smoothing capacitance from +-7mF to +-30mF for the pair of channels.
If I were building a PSX clone, I would be very tempted to use a similar sized transformer but put in two rectifying and smoothing banks using +-20mF per channel and still using the 5pin XLR to transfer the unregulated pair of lines into the amp.
This will require some PCB links to allow the power amp channels to run separately from the individual supplies. I would expect a further improvement in performance for little extra outlay.
Tell me what you think.
have a think about the Cyrus One & Two and try to imagine what the designer was trying to achieve.
The One had a small transformer that could by conventional design support an output of about 40W/channel.
The Two has the same smoothing capacitors and a bigger transformer that should be able to support 80W/channel. They spent the time and money developing and releasing this product and to me it seems obvious that they believed there was some performance advantage in using a transformer that is over-rated to about 160%. (VA>=1.5* maximum output power).
Users report that the PSX adds a little bit more and yet the transformer should be way over the top at about 300% over-size.
This leads me to suggest that the main performance enhancing characteristic is not the very large transformer, which can only help, but much more to do with the increase in smoothing capacitance from +-7mF to +-30mF for the pair of channels.
If I were building a PSX clone, I would be very tempted to use a similar sized transformer but put in two rectifying and smoothing banks using +-20mF per channel and still using the 5pin XLR to transfer the unregulated pair of lines into the amp.
This will require some PCB links to allow the power amp channels to run separately from the individual supplies. I would expect a further improvement in performance for little extra outlay.
Tell me what you think.
hi andrew i agree, sounds like a good idea ,worth trying. what about diodes is there audio grade types you can buy as i know with cd players the lower amp 11dq10 is a big upgrade from standard silcon types i would love to get more from the amp without getting a psx for now any ideas
thanks for your time Andrew
kieran
thanks for your time Andrew
kieran
Hi Andrew.
Still thinking about that.
I know from your other postings that you are an advocate of large capacitances in power supplies.
I have a Cyrus One and I'm about to attempt a repair.
Once it's up and running I will swap the 7mF caps for the 10mF from the Cyrus Two. Not exactly a conclusive test but should be interesting at least.
I would expect to hear a difference but we'll have to see.
Swapping transformers between them is another option but I'd have to research that further before blowing anything up!!
Are you saying that the increased transformer size in the PSX is disproportionate to the improvement? Is the PSX transformer so large that it has far exceeded the point of diminishing returns?
And, are you also implying that the amount of capacitance has not?
OK, So.... the first way to improve on the PSX would be to add more capacitance? The transformer and rectification could easily support this.
I agree that more capacitance is generally a good idea but I am perplexed by the apparent agility of the Cyrus One that has the smallest transformer and smoothing caps.
I don't claim to have golden ears but it just seems faster somehow. Is this due to a smaller power supply?
I like the idea of separate rectification and caps. I would definitely consider this if I didn't already have a PSX. Maybe one day I'll remake the PSX board without the +/- 18V supply and use the extra space for this. I can dream.
Cheers,
Martin.
Still thinking about that.
I know from your other postings that you are an advocate of large capacitances in power supplies.
I have a Cyrus One and I'm about to attempt a repair.
Once it's up and running I will swap the 7mF caps for the 10mF from the Cyrus Two. Not exactly a conclusive test but should be interesting at least.
I would expect to hear a difference but we'll have to see.
Swapping transformers between them is another option but I'd have to research that further before blowing anything up!!
Are you saying that the increased transformer size in the PSX is disproportionate to the improvement? Is the PSX transformer so large that it has far exceeded the point of diminishing returns?
And, are you also implying that the amount of capacitance has not?
OK, So.... the first way to improve on the PSX would be to add more capacitance? The transformer and rectification could easily support this.
I agree that more capacitance is generally a good idea but I am perplexed by the apparent agility of the Cyrus One that has the smallest transformer and smoothing caps.
I don't claim to have golden ears but it just seems faster somehow. Is this due to a smaller power supply?
I like the idea of separate rectification and caps. I would definitely consider this if I didn't already have a PSX. Maybe one day I'll remake the PSX board without the +/- 18V supply and use the extra space for this. I can dream.
Cheers,
Martin.
Sonusthree said:
Yes, take care with a full voltage PSX and those delicate transistors in the One.
Yes, I think the transformer rated at about VA=5*max power is well past the point of diminishing returns. This is not a ClassA machine nor a 4ohm capable device.
Yes, I think more benefit will come from separately driving each channel from it's own PSU.
Yes, there is more to come by increasing the capacitance to meet peak current demand which the transformer can never do.
Yes, the One may well suit treble or mid duty admirably. Maybe One for each!!! and keep the Two+dualised PSX for the bass. This will use up all the uncherished Cyrii out there
Geoff said:
Just to add further to the confusion, I repaired my friends Cyrus 2 which was an Issue 07 metal case version and it had Elna caps.
I also back up Andrew's opinion that making a DIY PSX with smaller transformer and using the real estate saved for separate left and right cap banks if not rectifiers as well, would be a better way forward than a straight PSX clone. The issue is getting the separated supplies to the amp, as the plug is only 3 pin and some track cutting may be required.
Kieran, you are very welcome.
Hifi collective lists longer versions of the same thing now and also connecting rods.
http://www.hificollective.co.uk/components/potentiometers.html
It's interesting that Cyrus seem to have changed from Slit foils at least for a while. Apparently the later PSXR uses Slit foils so they didn't stick with the decision. The PSXR also has less capacitance than the old PSX so maybe they decided that less Slit foil was better than More ELNA? Who knows?
My PSX would maybe have enough space for separate cap banks if it wasn't for the redundant 18V regulated supply. I would definitely love to remake my own PCB for the PSX. Probably with more but smaller caps for convenience.
Just need the tools and experience first......
Hifi collective lists longer versions of the same thing now and also connecting rods.
http://www.hificollective.co.uk/components/potentiometers.html
richie00boy said:
It's interesting that Cyrus seem to have changed from Slit foils at least for a while. Apparently the later PSXR uses Slit foils so they didn't stick with the decision. The PSXR also has less capacitance than the old PSX so maybe they decided that less Slit foil was better than More ELNA? Who knows?
My PSX would maybe have enough space for separate cap banks if it wasn't for the redundant 18V regulated supply. I would definitely love to remake my own PCB for the PSX. Probably with more but smaller caps for convenience.
Just need the tools and experience first......
Power with Cyrus One
Do you think it would be possible , in order to have more power, to connect only one Cyrus One (I have 4 of these) , to a bass loudspeaker (200w 8ohms), but connect input L+R together, and Output L+R together to get twice the current to a single bass loudspeaker ?
Is there any risk to blow up my Amp ?
Thanks !
R.C.
Do you think it would be possible , in order to have more power, to connect only one Cyrus One (I have 4 of these) , to a bass loudspeaker (200w 8ohms), but connect input L+R together, and Output L+R together to get twice the current to a single bass loudspeaker ?
Is there any risk to blow up my Amp ?
Thanks !
R.C.
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