aarond1553552714 Posted April 18, 2009 Share Posted April 18, 2009 Problem: I've got a Nordost heimdall XLR between my preamp and power amps. My Foreplay III valve preamp kit only has RCA inputs/outputs. Is it worth getting XLR - RCA adaptors to be able to use this favoured cable? if so, where can one get high quality adaptors? Other options: - Is it possible to get the cable reterminated, if so what would the cost be? Selling on TM and buying a new RCA heimdall means throwing many hundreds of dollars away, which I'd rather spend on CDs! Link to comment Share on other sites More sharing options...
NeilNZ Posted April 18, 2009 Share Posted April 18, 2009 Cardas do some really nice adaptors that I considered buying once. In the end just re-terminated the cable, easier, better in the long run and with no sonic deficiencies that I can hear... then again, I can solder, so unless you're confident of a good joint, maybe adaptors are the answer. Link to comment Share on other sites More sharing options...
KevinO Posted April 18, 2009 Share Posted April 18, 2009 Purist Audio Design also do some very nice adaptors. Link to comment Share on other sites More sharing options...
aarond1553552714 Posted April 18, 2009 Author Share Posted April 18, 2009 neil;89311 wrote: Cardas do some really nice adaptors that I considered buying once. In the end just re-terminated the cable, easier, better in the long run and with no sonic deficiencies that I can hear... then again, I can solder, so unless you're confident of a good joint, maybe adaptors are the answer. I'm terrified of the 'extruded micro-filaments' x 4 per cable, and trying to solder these all into the RCA connection... Link to comment Share on other sites More sharing options...
Ernie1553552694 Posted April 18, 2009 Share Posted April 18, 2009 aarond;89314 wrote: I'm terrified of the 'extruded micro-filaments' x 4 per cable, and trying to solder these all into the RCA connection... Jeez Aaron, why don't you talk to a Nordost dealer , they should be able to factory reterminate them for a reasonable sum of money. As an indication, the same cable in balanced terminations cost an extra $100. If you only have to terminate at one end... well, you fill in the dot! Link to comment Share on other sites More sharing options...
Ernie1553552694 Posted April 18, 2009 Share Posted April 18, 2009 Um, wait a minute Aaron, is it possible to put balanced outputs on your Foreplay? That way, you don't have to desecrate your Heimdall. Link to comment Share on other sites More sharing options...
aarond1553552714 Posted April 18, 2009 Author Share Posted April 18, 2009 Ernie;89318 wrote: Um, wait a minute Aaron, is it possible to put balanced outputs on your Foreplay? That way, you don't have to desecrate your Heimdall. Hmmmm - that sounds like an interesting idea... But then again it might be just as easy to get adaptors for one end. I'm not going to cut my cable up.:eek: I know it is only a simple operation, in and out in 15mins, but it is my cable... Link to comment Share on other sites More sharing options...
Ernie1553552694 Posted April 18, 2009 Share Posted April 18, 2009 aarond;89319 wrote: I know it is only a simple operation, in and out in 15mins, but it is my cable... With you there... Link to comment Share on other sites More sharing options...
NeilNZ Posted April 18, 2009 Share Posted April 18, 2009 aarond;89314 wrote: I'm terrified of the 'extruded micro-filaments' x 4 per cable, and trying to solder these all into the RCA connection... Nah, I've re-terminated Nordost in the past, its not any different to any other cable when you get down to it. but I would do as Ernie suggests and get it to a dealer. Link to comment Share on other sites More sharing options...
Ernie1553552694 Posted April 18, 2009 Share Posted April 18, 2009 Factory terminations mean the lifetime warranty would stay intact. That's if Aaron was going that way... Link to comment Share on other sites More sharing options...
Antipodes1553552706 Posted April 18, 2009 Share Posted April 18, 2009 Reterminate both ends, if you are wedded to the Foreplay that is. The adaptors will not sound great and I would only consider them if the Foreplay was not likely to be a keeper. And driving single ended into the balanced inputs on your amp is likely to sound worse than into the single ended inputs (based on how most amp's inputs are designed - but does depend on your amp). Link to comment Share on other sites More sharing options...
Halo88 Posted April 18, 2009 Share Posted April 18, 2009 Hi aarond, IMHO fitting XLR sockets to your Foreplay preamp would be the best solution. Re terminating your Nordost cable would involve returning it to Nordost USA in order to retain the warranty & resale value. A hybrid XLR/RCA cable would be an orphan, & very difficult to sell, a lot of its value would be lost.:eek: By contrast a fully balanced system does lower the noise floor, & is preferable. Regards. Link to comment Share on other sites More sharing options...
Shane Hanify Posted April 18, 2009 Share Posted April 18, 2009 aarond;89309 wrote: Problem: I've got a Nordost heimdall XLR between my preamp and power amps. My Foreplay III valve preamp kit only has RCA inputs/outputs. Is it worth getting XLR - RCA adaptors to be able to use this favoured cable? if so, where can one get high quality adaptors? Other options: - Is it possible to get the cable reterminated, if so what would the cost be? Selling on TM and buying a new RCA heimdall means throwing many hundreds of dollars away, which I'd rather spend on CDs! I can't comment on the quality, but you can try ... http://www.audioshop.co.nz/connectors/connectors1.htm They have XLR > RCA adapters listed there for only a few $ each, so you could certainly try it. Cheers, Shane. Link to comment Share on other sites More sharing options...
dexterg Posted April 18, 2009 Share Posted April 18, 2009 If you go the adapter way just make sure you get the right 'hot' and 'cold' pin combination, ie, pin 2 is usually hot with pin 3 cold, however Japanese gear and some others is the reverse. Cardas offer both. Link to comment Share on other sites More sharing options...
Owen Y Posted April 19, 2009 Share Posted April 19, 2009 I'd preserve the (authenticity of the) Nordost cable & consider installing XLR outs on the Foreplay. Talk to Clarry, if he still has the Foreplay (& maybe show him the Poweramp/s or cct diag of same, for info). You will then also be able to play with RCA & XLR terminated cables in the future. My 2cents. Have I missed anything here? Link to comment Share on other sites More sharing options...
Owen Y Posted April 19, 2009 Share Posted April 19, 2009 Postscript: I see from the other thread that the Foreplay is back from Clarry's... Definitely check out the possibility of using the XLR Nordost with the Foreplay. That should give it a fairer chance of smoking that Plinius Link to comment Share on other sites More sharing options...
Antipodes1553552706 Posted April 19, 2009 Share Posted April 19, 2009 The simplest way to add balanced outputs for the Foreplay is to add an output transformer on each channel. You could, of course, put XLR outputs on the Foreplay and connect signal hot to pin 2, and signal earth to both pin 1 and pin 3 (and try this again lifting pin 3 to see which sounds best). It won't be a balanced output but does do away with the use of adaptors, and any need to change the cables, which is a good idea Halo88. Link to comment Share on other sites More sharing options...
aarond1553552714 Posted April 19, 2009 Author Share Posted April 19, 2009 Antipodes;89410 wrote: The simplest way to add balanced outputs for the Foreplay is to add an output transformer on each channel. You could, of course, put XLR outputs on the Foreplay and connect signal hot to pin 2, and signal earth to both pin 1 and pin 3 (and try this again lifting pin 3 to see which sounds best). It won't be a balanced output but does do away with the use of adaptors, and any need to change the cables, which is a good idea Halo88. I'm not sure what you mean by 'adding an output transformer on each channel'. Doesn't sound terribly simple to me. :confused: If I put in a balance output and wire it as suggested here, how would this affect the amplifier at the other end receiving the signal? My understanding is that the balanced signal comprised two parts that are summed which results in rejection of noise common to both parts, if one of these parts is grounded at the preamp end, won't this mean that the power amp end is not going to be able to reconstruct the signal properly? Please excuse my lack of knowledge and thanks for all the suggestions, so far I am not going to chop my cable and i'm vering away from the use of adaptors as they are likely to be terribly expensive or deliterious to the sound. Link to comment Share on other sites More sharing options...
Owen Y Posted April 19, 2009 Share Posted April 19, 2009 On 2nd thoughts, aaron, as this whole issue of inserting XLR ouputs into a non-balanced pre & XLR connection to unbalanced equipment (the power amps?)... can yield unpredictable results... The best & cheapest first approach would prob be to use some of those RCA/XLR Adaptor plugs. Arguably a loss of fidelity maybe, but an affordable experiment, & to verify if it all works satisfactorily. Link to comment Share on other sites More sharing options...
aarond1553552714 Posted April 20, 2009 Author Share Posted April 20, 2009 Owen Y;89491 wrote: On 2nd thoughts, aaron, as this whole issue of inserting XLR ouputs into a non-balanced pre & XLR connection to unbalanced equipment (the power amps?)... can yield unpredictable results... The best & cheapest first approach would prob be to use some of those RCA/XLR Adaptor plugs. Arguably a loss of fidelity maybe, but an affordable experiment, & to verify if it all works satisfactorily. My exact, current, thoughts! I'm making some enquiries at the moment, I'd certainly prefer to borrow some good ones to trial. It seems crazy to be so focused on one pair of wires, but they were a heavy investment (one that still makes sense in the context of the SS system). Link to comment Share on other sites More sharing options...
Owen Y Posted April 20, 2009 Share Posted April 20, 2009 Looks like Neutrik do a range of them, eg. RS NZ... http://newzealand.rs-online.com/web/search/searchBrowseAction.html?method=retrieveTfg&binCount=60&Ne=4294960157&N=4294864577+4294856529 30 bucks ea. Link to comment Share on other sites More sharing options...
aarond1553552714 Posted April 20, 2009 Author Share Posted April 20, 2009 Owen Y;89506 wrote: Looks like Neutrik do a range of them, eg. RS NZ... http://newzealand.rs-online.com/web/search/searchBrowseAction.html?method=retrieveTfg&binCount=60&Ne=4294960157&N=4294864577+4294856529 30 bucks ea. Thanks Owen, though at $120 for a set it might be a cheaper option to re-terminate... Link to comment Share on other sites More sharing options...
Owen Y Posted April 20, 2009 Share Posted April 20, 2009 Don't you need just a pair, at the preamp end? Link to comment Share on other sites More sharing options...
Ernie1553552694 Posted April 20, 2009 Share Posted April 20, 2009 aarond;89502 wrote: My exact, current, thoughts! I'm making some enquiries at the moment, I'd certainly prefer to borrow some good ones to trial. It seems crazy to be so focused on one pair of wires, but they were a heavy investment (one that still makes sense in the context of the SS system). I'd probably recommend just using the RCA connections for the time being. A Nordost power cable will probably have a greater effect. You aren't really running true balanced signals so you might be barking up the wrong tree. Adapters will lower the impedance of the signal. Otherwise what will a pair of output transformers cost to install in the Foreplay? Link to comment Share on other sites More sharing options...
Antipodes1553552706 Posted April 21, 2009 Share Posted April 21, 2009 As first mentioned by Halo88, you can avoid the adaptors by installing XLR output connectors and wire them exactly the same way as the adaptors do. It will be cheaper and sound better (exactly the same wiring but eliminating a connection and a set of connectors). There is no problem with driving this into the balanced inputs on your amp, whether you do this with adaptors or an XLR output connector. The positive and negative signals are replicas of each other, just out of phase. The balanced input will take it in as a differential input and the positive to negative swing is simply twice the voltage difference of the positive to ground swing, otherwise the same signal. The idea of the output transformers was to provide a differential output from the preamp that was truly balanced, but it isn't necessary. Hope that helps. As stated, you can avoid the adaptors altogether with two XLR outputs and a little time to install it. Link to comment Share on other sites More sharing options...
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