So after getting the Cyrus 3 Power Amps happily installed I really wanted to know whether balanced XLR or un-balanced RCA connections were going to sound the best, and secretly I really wanted XLR to win.
I hate interconnects. They are always too short, too expensive, and never enough of the same type to match. It's a complete tyranny in Hifi circles, you have to have the "Right" cable. That cable is then ludicrously expensive, and hence short, and short is also supposed to sound better, so some are REALLY short, then suddenly you can only plug your hifi together in maybe one or two configurations without straining any of the leads, and almost certainly that isn't the configuration which would be naturally ergonomic, or often even practical. But it's notionally going to sound better, and you've invested all this money in shiny gold, silver, copper and PFTE you aren't going to compromise it just because it makes the the buttons difficult to reach. By the time I've got a digital system to play nicely with my analogue system and both to play nicely with movies, that is a lot of boxes and cables and I'm fed up with them telling me how to organize my kit instead of the other way around.
So balanced is the great hope, use a technology which makes you less dependent on the type of cable, less dependent on the length. Buy some good but not silly cable, some nice connectors and make your own the right length. One nice soldering iron and silver solder (the states type you aren't supposed to use in the EU) and I was ready to give it a go.
So balanced is definitely the way to go if
1) You need long lengths of line level connections (say if you want your amplifier in different rooms)
2) If you have a lot of radio frequency interference (RFI)
3) You have kit which is designed from the start only to use balanced.
Balanced if perfectly implemented should be superior, but it's quite rare in kit in the UK, more common in the States, and on less than very expensive kit often it can be an added on after.
So we have the Cyrus 3 Power Amp - offering a balanced XLR imput and an unbalanced RCA input - which sounds better?
These were my creation of test cables, 2.75m long, Neutrik NC3FXXB and NC3MXXB connectors, Van Damme Tour Grade Classic XKE microphone cable, Qables 6.5mm Y-Splitters (to avoid having to daisy chaining with an RCA) This is a spec you'll find widely on forums for instance on Hitchhikers here. Having made a setup I can thoroughly recommend all of it - very nice kit. Probably about £35 of parts. Most from VDCTrading apart from the splitters which are well recommended by headphone enthusiasts from Qables
These were up against my chosen RCA cable of choice from way back when, the Chord (Silver0 Siren. Silver plated conductors, Teflon outer, nice RCAs. I've gone through and reconditioned all of mine recently as some of the RCAs developed intermittent connections. Taking a deep breath and cutting my limited collection of 1m pairs in order to make some really short ones for daisy chaining and linking power amps and meaning I could use them for all my power side. Chord Silver Siren was about £65 RRP if I remember. So expensive, short and a fetching shade of matching.purple which pleased me greatly.
So the Cyrus 3 is quite a popular model, more expensive second hand that some that came after without XLRs. Is it worth it.
I really wanted the balanced to sound better, but on this amp, in this test it doesn't. The RCA option is more transparent, more open and fresh. Not that the balanced is bad, if you weren't doing a back to back you wouldn't notice. But not a retrograde step back I was prepared to solder a complete set of cables and switches to take.
Yes balanced *should* be better, but in this case, on this amp, it isn't and I'm not alone in thinking this. Various threads on Cyrus forums here
So if you are buying a Cyrus 3 for the balanced connections for sound quality (rather than dealing with distance runs) don't bother.
So this isn't a hugely precise test. Ideally it should be exactly the same length and cable type balanced and unbalanced to get a precise answer. But for me it doesn't matter, balanced was a route to great sound with longer cables, and with more widely available cables at low cost and that I could adjust cables without such a very deep breath before cutting precious materials. So regardless of which part of the picture, the length, the pure copper rather than silver, the insulation, the internal balancing circuitry in the amp, it doesn't matter the RCA sounds better, and I'm back under interconnect tyranny.
At this point I'd really like to state how nice the balanced materials were to work with.. If anyone is out there designing an amp from scratch, design it to have XLR end to end. Solid, reassuring, and the right size for my fingers and level of dexterity. RCA isn't.
The Neutrik and Van Damme stuff is made in huge quantities for stadia, studios, and outdoor broadcast. It's lower cost because of volume at the same time as being beautifully made. The plugs have enough space to solder and get a really nice connection on them, even if you aren't a soldering master. They grip the cable fantastically and support the connection, with a dedicated shield stopping shorting out against the case even if you are stretching and abusing the connection. The plugs lock in and out of components they have metal solid ends, nice tactile flexible ends. They are in short friendly, robust and everything most hifi plugs aren't.
The Van Damme cable is very pure, well shielded, strengthened with really nice string cord internally flexible outer insulation, stiffer inner insulation, strips nicely, cuts nicely, feels nice in the hand. Again everything Hifi cables often aren't.
Hifi cables almost seem to have to be awkward to use otherwise you aren't sacrificing enough for the sound!