Cyrus 2 + PSX renovation thread

[MajorFubar]

I fell in love with the Cyrus sound when I was 18 in 1988. I borrowed a very early Cyrus 1 from a college mate, and even through my relatively-humble 2nd-gen Wharfedale Diamonds it was so far ahead of what I was currently using it was untrue. I fell in love as well with the half-width shoe-box size, the minimalst design philosophy, and the absolutely unassuming appearance of having been thrown together by a couple of teenagers in a 'resistant materials' GCSE class.

Fast forward to about 2010/2011 and I managed to buy a used issue 7 Cyrus 2 in peely nextel grey for much cheapness when a house-clearance seller advertised it as DOA. But the photo made it clear the amp had at some point been used with a PSX and I hedged my bets that it was just needing the two T4 fuses replacing on the circuit board which are removed to make it PSX compatible. I was right, and it worked kind of well except for having a faulty MC stage. Later I bought a PSX (sadly non-matching cosmetically, until I sprayed both it and the amp black) and I used them together for a while, and loved them, before money-problems meant I had to sell. Since then I've been using a Marantz PM66KI, kindly donated from my very elderly dad who no longer uses it.

I didn't really have any thoughts about revisiting old Cyrus gear, but when a young workmate's grandad died recently and he was clearing the old man's loft, he found a pair of very dusty but basically tidy 'old hifi thingies' that he thought I might be interested in. Turned out to be a very late (but sadly unboxed) issue 7 black Cyrus 2 and PSX, just like the ones I had had to sell, but presumably black from the factory this time, instead of from a can of high-temperature matt-black stove paint. Fully admitting he didn't really know what they were and couldn't test them ("where's the iPod socket?!") I couldn't resist but settle a fair price with him sight unseen except for this blurry phone pic:

I have offered him substantially more than he thought they were worth, on the agreement that I find them working and they're not just two 4kg doorstops. Maybe I'm a fool and I should just have given him the price he first suggested, but my conscience is at least clear. Tomorrow I will bring them home. I'm not sure what state I will find them in, in terms of how well they function; a decade in the loft will probably not have done them many favours. We shall see.

Kinda sad I know, but buying or refurbing old gear like this excites me far more than buying anything new. I intend to refurb them, cosmetically and electrically (I'll probably farm-out anything I'm not confident with to a specialist, such as re-caps should they need it) and then when I'm finished, decide what to do with them. Bit of a labour of love I suppose to keep me busy over winter.

 

[expat_mike]

Nothing to apologise for.

I think many of us are probably toying with ideas of projects for the winter months.

 

[MajorFubar]

Well here they are, after a damn good clean:

I'm surprised how great condition they are cosmetically, as I understand they weren't stored particularly well in the loft, and the dust and dirt I cleaned off were testament to that. I've already been inside them both and 'swept up' in there as well. I had visions that I'd probably have to repaint them both but to be honest I reckon I can get away doing very little. The PSX has a scratch down the rhs cheek about 6" long, but not completely through to the alloy, which is conducive with it being dragged along something sharp like a nailhead at the side of a shelf when it was being extracted, so I'll probably just take the lid off, flatten that one side and respray just that.

Thankfully the facias are tidy on both of them and I don't have to repaint them. The facia panels are more difficult to respray than the lids because the mains switches have to be unsoldered before the facias can be completely removed from the chassis/PCBs, plus the legends are nearly impossible to take off intact. In fact everything about repainting the facia panels is just a fiddy arsey job that I'd rather not bother with, and so I'm glad I don't have to.

Electrically, things are not so great. Everything seems to fundamentally operate, but the Alps selector switches are noisy and intermittent (switch cleaner will almost certanly be a waste of effort here as I suspect the contacts have tarnished) and most of the RCA inputs on the back don't work on both channels without wiggling the interconnects. Thankfully the irreplaceable dual-ganged balance/volume pots seem to be absolutely fine.

Some of the electrolytics appear to be past their best though in the amp; there is some early signs of leakage and bulging on a couple, and I think after repairing what I can of the amp on my own (such as rebuilding the Alps switches and resoldering the offending RCAs) I will almost certainly send it away for a re-cap using more modern components. Thankfully the reservoir caps in both the amp and the PSX are completely fine, which I'm pleased about because the 15000µF caps in the PSX don't come cheap (about £25 each for decent Panasonic ones, though inexpensive knock-offs from China are available...).

Updates to follow as time allows.

 

[Infiniteloop]

An enthralling story. I hope they serve you well for many more years.

 

[MajorFubar]

An enthralling story. I hope they serve you well for many more years.

Truth is I'm not even sure if I intend keeping them! I'm getting most of the enjoyment from actually doing the rebuild process, though a few of the more intricate jobs like the re-cap I'll probaly farm-out because I only have one hand and I find it very fiddly. Keeps me out of mischief though!! :-D

 

[Infiniteloop]

An enthralling story. I hope they serve you well for many more years.

Truth is I'm not even sure if I intend keeping them! I'm getting most of the enjoyment from actually doing the rebuild process, though a few of the more intricate jobs like the re-cap I'll probaly farm-out because I only have one hand and I find it very fiddly. Keeps me out of mischief though!! :-D

Now I'm even more enthralled and take my hat off to you. - I'd be too scared to even attempt going near an Amp's innards.

 

[MajorFubar]

Thank you

 

[drummerman]

Have fun

 

[Infiniteloop]

What's interesting about these units is how little the styling has dated. - They look much better than the current Cyrus boxes, which strangely look more dated than these do.

 

[MajorFubar]

Have fun

Yep that's what hifi should be all about

 

[MajorFubar]

What's interesting about these units is how little the styling has dated. - They look much better than the current Cyrus boxes, which strangely look more dated than these do.

It's probably a matter of taste I guess, and dare I be so bold as to suggest without knowing your particulars, possibly age. I'm 'over 40' (!) and I agree with you, but my young work friend from whom I bought them thought they looked like some relics from the stone age because of their large clunky controls. When he brought them in today he apologised for not being able to find the remote. When I told him there wasn't even a remote, the look I got from him was as though I'd told him 'you need to wind them up with a key.'

 

[Infiniteloop]

What's interesting about these units is how little the styling has dated. - They look much better than the current Cyrus boxes, which strangely look more dated than these do.

It's probably a matter of taste I guess, and dare I be so bold as to suggest without knowing your particulars, possibly age. I'm 'over 40' (!) and I agree with you, but my young work friend from whom I bought them thought they looked like some relics from the stone age because of their large clunky controls. When he brought them in today he apologised for not being able to find the remote. When I told him there wasn't even a remote, the look I got from him was as though I'd told him 'you need to wind them up with a key.'

I'm in my early fifties with over three decades under my belt as an industrial designer and latterly Creative Director for two companies who export to over 140 countries. - You can see I've been around a bit!

I think they look pretty current, as retro is a big trend, particularly Scandinavian design from the seventies....

 

[MajorFubar]

...retro is a big trend, particularly Scandinavian design from the seventies....

Old saying what goes round comes round I guess!

 

[Benedict_Arnold]

Back in the 80s, a friend of mine was in his final year doing Physics at Royal Hoolway and Bedford.

His final year project was building a dectector to receive messages from the Giant Spaghetti Monster in the Sky or something and involved one of those new fangled silicon chip things. Appaarently it cost nearly two grand, back in 86 or 87.

Anyway, he asked his Professor what would happen if he messed up the chip.

"You'll be a doing one heck of a lot of soldering, son" was the reply.

Hope you're a dab hand with the soldering iron. It sounds like a great project for the Winter months and the sound of the refurbished amp may surprise you.

 

[CnoEvil]

I wish you luck with your project, Major....and I have faith that FUBAR won't be the outcome!

 

[rainsoothe]

I think it looks beautiful

 

[MajorFubar]

Thanks for the very kind comments guys.

I wish you luck with your project, Major....and I have faith that FUBAR won't be the outcome!

Ha! I truly hope not :-D

 

[MajorFubar]

If you've ever wondered what lay under the lid of one of these but were too scrared to look, you're not missing much to be honest. Other than a mahoosive transformer, a rectifier circuit, four expensive 15,000µF reservoir capacitors and a few bits and bobs to make it all work together, there's not much to see.

Inside of mine was fairly tidy other than localised corrosion around the DIN socket that supplies PSX power to the PCM II CD player, and one of the cable-ties had come loose from the side of the chassis due to age:

Interestingly none of these Cyrus amps or PSXs from this era are voltage-switchable for different markets. Instead the transformer has multiple outputs. The correct combination of cables from the transformer are plugged into the PCB at the factory, depending on the intended market. If course this stops you from blowing the circuitry by accidentally changing the voltage regulator, but it's a bit inflexible if you move overseas to a different supply, such as the US.

The old trick of tinfoil and vinegar (often used in classic car circles to de-rust chrome bumpers) made the DIN socket a bit tidier:

...while Superglue proved itself worthy of gluing the cable-tie back to the chassis:

I could kick myself for not taking a photo of the scratch down the side of the case before I resprayed it, because without it I can't give you a before and after. None the less this is that after:

A tiny remnant of the scratch about 3/4" long can be seen two thirds of the way across, but compared to the 6" long gouge that was there before, I can live with that. In fact most people probably wouldn't notice the mark if you didn't point it out to them.

If you were wondering what paint I used, I used high-temperature matt black stove paint, which in summer is commonly marketed as barbeque paint. The appearance is near indistinuishable from the original paint, with the same lightly textured finish. I gives better results than satin-black hammerite, and unlike hammerite, it doesn't react with existing paint.

There's really not much to go wrong with these, they either work or they don't, and other than replacing the £25-a-pop reservoir capacitors there isn't much to service.

Next, I will turn my attention to the cosmetic appearance of the Cyrus 2 prior to stripdown. Possibly that will be next week due to other commitments.

Thanks for reading my ramblings.

 

[MajorFubar]

Found some spare time today to begin work on the amp. I'd already swept most of the dust out of it the other day so no surprises that it's comparatively clean:

The circuitry in the Cyrus 1 and 2 is very modular. Moving clockwise from bottom left (from this view at least) is the PSU section with the transformer, rectifier and two reservoir capacitors. Across the top are the RIAA EQ circuits for MC and MM cartridges, and the bulk of the rest of the circuitry is the power-amp section, heat-sink, and the sockets. The green ribbon cable couples the RCA sockets to the PCB. With this in mind, I'll let you decide for yourself why I have a healthy skepticism for stupid audiofool interconnects.

These Alps switches control the source selection and record-out selection:

Their operation is very intermittent and they will need to be unsoldered, disassembled and cleaned. They don't help themselves by having holes top and rear which are open doors to dust, even with the amp's (vented) lid in place. Switch cleaner had virtually no effect.

Here's one of the small anomalies of 'Issue 07' Cyrus 1 and 2 amps: the legends on the PCB show one of the inputs was to be labelled as 'Tuner', whereas both the panel in the lid and the front fascia panel show that input as 'Aux':

Just to confuse the new owner (who wouldn't of course have seen the PCB), the input is also referred to as 'Tuner' in the manual. I have a theory for this which I'll mention at the end of my post. Just to the right you can see the solder-points for the (by now, deleted) headphone socket. Prior to being deleted in May 1989, it had been variously on the rear (on the very early models), on the side and on the front. On the rear it was 1/4" but on the side and front it was 3.5mm. In all versions it didn't mute the speakers. With no other method to silence the speakers except unplug them, it was of limited use.

My second bit of repainting following the side of the PSX the other day: the control knobs. The balance control is plastic but the volume and the source selectors are metal over plastic shafts. There were minor scratches to all three front surfaces and the volume knob was showing some paint-wear around the knurled ring. I had worried that the hardest part of repainting them would be de-greasing them, but I had an idea to remove the knobs from the shafts leave them standing overnight in a small tray of vinegar. Problem sorted and after having sprayed them and re-united them with their plastic shafts, they look good as new:

And here's the amp reassembled, minus the knobs. I 'fed' the paint with some Autoglym Bumper and Trim Gel applied with a 50p shoeshine sponge, then after a few minutes wiped it dry:

I can see me respraying the top of the lid at some point, I really don't like the look of what's happening here:

Much like old rusty cars where corrosion to the metal beneath causes the paint to bubble, I suspect there is some chemical reaction under the bubble. This isn't going to fix itself of course. This can be a final task when I've finished the electrical jobs.

Oh...and why was 'Tuner' changed to 'Aux' after both the PCB and the manual had been printed with 'Tuner'? Simple: the word 'Tuner' didn't fit in the narrow space on the front panel.

Thanks for reading.

 

[Rethep]

Nice job!

I have auditioned the Cyrus 2 in those times (around 1988 or so), when looking for new speakers. A very nice design! But in the end i never owned one.

 

[MajorFubar]

Thanks. I've just this evening finished packaging it all up. I've taken the decision to wing it off to a specialist in Suffolk for a re-cap, because that's just a bit too fiddly for my personal dexterity, seeing that I have one arm less than the accepted average. He completes an Alps rebuild and re-biasing as part of the job, the first of which would still have been a major PITA to do even though I did intend doing it on my own, and re-biasing I don't have the equipment to do.

Suspect the money I'm about to throw at it will probably scupper my chances of breaking even if I decide to sell it, even though I acquired it and the PSX for a very nice price.

 

[drummerman]

When I first relocated to the UK, a long time ago, a friend, then a student, had one of the first cyrus's, a rega turntable and a pair of Mission speakers with some translucent plastic cones.

All I remember was thinking this sounds lovely.

 

[MajorFubar]

a pair of Mission speakers with some translucent plastic cones.

All I remember was thinking this sounds lovely.

Possibly 751s, DM?

 

[drummerman]

a pair of Mission speakers with some translucent plastic cones.

All I remember was thinking this sounds lovely.

Possibly 751s, DM?

No, more like 764 or similar.

 

[MajorFubar]

Ah, big monsters then

Definitely the key to getting the best from these early Cyrus amps is complimenting them with just the right speakers that don't accentuate their slightly forward balance. Get it right and the amp presents you with a doorway to the music like I personally have never heard from any other amp I have been able to afford. The dynamics and depth, and the clarity in the midband are IMO astonishing. My PM66KI is overall more approachable but it doesn't come near lifting the veil in the same way. Not nearly close.