I've heard many differing opinions on this.
All I can say, is with my BAT VKP10SE, which has a balanced input section, using a din to XLR cable gives a quieter, more deatailed presentation than a din to RCA tonarm cable.
For me and my setup, it helps. Not huge, but noticable. |
If you don't have a fully balanced system you are not gaining anything by adding balanced phono corrector. |
Is there a "balanced" signal coming from the cartridge?
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There seems to be some confusion here.
A phono cartridge is inherently balanced. That is, it has separate hot and neutrals for left and right, and one shield.
There are no better places to run balanced connections than from your phono cartridge into your phono preamp, and then from your phono preamp to your line stage. If those are truly balanced (differential) amplifiers, then balanced connections should yield the highest gain and the lowest noise.
If the "balanced" amplifiers aren't really differential amplifiers - but use op-amps on the inputs and outputs to process balanced connections - then you may lose some of the benefits of a truly balanced set of connections. But with phono connections, it's still likely to result in the lowest noise.
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Do you know of a manufacturer who makes a balanced XLR-XLR phono cable, or is any balanced cable going to work well?
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Whether it's a moving coil type or a moving magnet type or any of the variants thereof, the signal comes off a coil of wire. At either end of the coil, the signal looks the same, except for its being opposite in phase. So, a cartridge is an inherently balanced output device. When you run it into a typical standard single-ended phono stage, you make an arbitrary choice to take the signal off one end of the coil and to ground the other end. But there is no need to connect to ground. In balanced mode, you just connect the coil to another identical circuit. Because the two signals are 180 degrees out of phase, any noise common to both signals is cancelled. You get a bit more gain in balanced mode and that advantage of noise cancellation, known as Common Mode Rejection. Brrgrr, usually you won't want an XLR to XLR phono cable. Usually you will want a DIN to XLR cable, to connect your cartridge to a balanced phono input. Yes, they are made, can often be custom-made too.
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lewm " ... You get a bit more gain in balanced mode ..." If you’re using truly balanced, differential amplifiers, you can pick up 6 dB of gain going with balanced connections. That’s a lot of "free gain" when we’re talking about a phono-level signal. " ... usually you won’t want an XLR to XLR phono cable. Usually you will want a DIN to XLR cable, to connect your cartridge to a balanced phono input." Not necessarily. You’ll want to use the connectors appropriate for your system. For example, some balanced phono preamps use RCA connectors on the inputs and a ground wire separate from the signal’s neutral. ARC phono preamps work this way and as long as you keep the shield electrically separate from the neutral, you’ve maintained the integrity of the balanced connection. Some users prefer that the phono cable go straight from the pickup arm to the phono preamp, but that isn’t always possible. VPI arms, for example, won’t allow that - you’ll need to go from the arm’s breakout box to the phono section. I’m pretty sure that VPI uses RCA connectors on that box, but I think they may offer one using XLRs. But either way, as long as the shield is electrically isolated from the signal neutral, you’ve kept your balanced connection. Some audiophiles object to phono cable breakout boxes, believing that the extra connectors compromise signal quality. I like to use a breakout box, but you’ll want to choose one that uses only the best wire and connectors if you go that route. |
The signal from phono cartridge actually comes BALANCED. Each channel has +, - and ground. all you need to do is separate ground between 2 XLR connectors. There's also phonostage that uses 5-din receptacle. Check out Violectric P600. http://violectric-usa.com/pre-amplifiers/ppa-v600Not associated with this company, but really like the adjustable gain on front panel. |
CLeeds, Please note that I used the word "usually" when describing the cable needed. You've pointed out the cases where one would do other than the usual. I was trying not to overwhelm Brrgrr with details. Thanks.
You wrote, "For example, some balanced phono preamps use RCA connectors on the inputs and a ground wire separate from the signal’s neutral. ARC phono preamps work this way and as long as you keep the shield electrically separate from the neutral, you’ve maintained the integrity of the balanced connection."
The user should beware of using an RCA-terminated IC for balanced phono, since in that case it is possible that one half of the signal, which for convenience we can call the negative phase, is being carried on the cable shield. (There is no "neutral" in the balanced mode.) That is a compromise I would not care to make. If the cable is knowingly constructed for balanced operation using RCA terminations, then the maker can use two conductors of equal quality for each "half" of the signal, one going to the central pin and the other going to the collar normally used as ground. But inside the phono stage, that collar must be connected to the circuit that amplifies and RIAA equalizes the negative phase, not to chassis ground. (Does ARC do this?) Otherwise, you don't have balanced operation. Any ground wire is just to keep the phono stage/tonearm/turntable at the same electrical ground point. It can be completely external to the cable itself, as I think you say. In balanced mode, audio ground can float.
Are you sure that ARC phono stages that purport to be truly balanced use RCA input jacks? (I've never seen one in the flesh, much less owned one.) Seems to me they ought to at least offer the option of XLR input, along with RCA. I can see why they might provide an RCA option, since most phono cables are RCA-terminated, and since most audiophiles are hopelessly confused about balanced operation. Every other true balanced phono stage I know about provides XLR inputs, plus or minus RCA inputs.
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only if you have your VPI with XLR outputs, and all your other components that work differntially balanced. To be correctly balanced, electronics should have completely seperate circuits for the plus and minus portions of the signal.... Most companies put on XLR connections and call their component balanced to add cache to their product....that isn't really balanced. Because of the separation, there are many more parts and therefore greater cost in balanced circuits.
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^^ just a point of clarification, if the circuit is differential (a form of balanced operation) then the 'plus and minus portions of the signal' are handled by circuits that are **not** 'completely separate', in fact the circuits must be intimately connected to each other to create the differential operation.
A nice advantage of balanced operation with phono is the fact that the interconnect cable need no longer impose a sonic artifact on the signal. If you've ever heard of someone paying $1K for a phono cable, you know what I mean. The balanced line system was created to eliminate interconnect cable artifact and this **really** works out well with phono cartridges, since imposing artifact that that point would be at the earliest point in the system!
FWIW we make a variety of inexpensive (since balanced operation eliminates cable artifact, they don't have to be expensive anymore) balanced cables for phono use. We were the first manufacturer anywhere to use balanced inputs for phono operation.
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Plus, you can put your table 200 feet away from the preamp. |
lewm
"CLeeds, Please note that I used the word "usually" when describing the cable needed. You've pointed out the cases where one would do other than the usual."
Oh yes, duly noted. Fair enough.
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The user should beware of using an RCA-terminated IC for balanced phono, since in that case it is possible that one half of the signal, which for convenience we can call the negative phase, is being carried on the cable shield. (There is no "neutral" in the balanced mode.) That is a compromise I would not care to make. "
Agreed!
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Are you sure that ARC phono stages that purport to be truly balanced use RCA input jacks?"
Yes, absolutely. |
czarivey "The signal from phono cartridge actually comes BALANCED. Each channel has +, - and ground. all you need to do is separate ground between 2 XLR connectors."
There's nothing magical about XLR connectors. You can maintain balanced operation by using RCA connectors, but you must keep the ground separate from the neutral or - as others have also pointed out - more correctly the opposite phase signal. |
I use and recommend the Ayre P-5xe mp phono preamp. Its not worth it unless your whole chain is balanced. Moon-audio & Grover Huffman can make custom cables for mini din to xlr. You can download the manual for the Ayre and see schematics for acceptable cable wiring. I like to use the shortest and smallest gauge wires with good shielding for phono cables.
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I owned an Ayre P5Xe-mp, and selling it was a mistake. It was great as a spare and as a second phono stage for MM/MI. So, I second your nomination.
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