Jhsg Posted July 23, 2020 Share Posted July 23, 2020 (edited) Hello everyone, Just seeking some advice regarding earthing my equipment. My situation is I have a REL Sub which is connected to my balanced amp via high level input - one wire running to each of the positive speaker connectors and the black / earth wire not connected to anything as the amp is balanced and the manual tells me the negative speaker outputs are not earth. When I am running the system everything is fine but when i switch off the amp i get a persistant hum from the subwoofer. There are plenty of information online where people have the same problem and there is an aftermarket earth kit for my amp but I need to get it from the USA which will take some time in the current C19 enviornment. So my question..... To acheive earth and get rid of the hum, am I able to connect the REL high level input earth wire on another piece of equipment that isnt always in the signal chain? I am thinking I will run the earth to my marantz AVR signal ground terminal. I am just worried that with it not being in the signal chain it might cause some damage? Hopefully this post provides enough information. Thanks in advance for any help. Regards, JH p.s. here is a link to people talking about the problem. https://forum.psaudio.com/t/bhk-pre-and-power-on-the-way-rel-subwoofer-question/3662?page=2 Edited September 7, 2020 by Jhsg Link to comment Share on other sites More sharing options...
awayward Posted July 24, 2020 Share Posted July 24, 2020 Is it a differential amp, if so the black wire should not be connected. 1 Link to comment Share on other sites More sharing options...
Jhsg Posted July 24, 2020 Author Share Posted July 24, 2020 (edited) 3 minutes ago, awayward said: Is it a differential amp, if so the black wire should not be connected. Thanks mate. Would it be okay to connect the black / earth wire to my marantz? Edited July 24, 2020 by Jhsg Link to comment Share on other sites More sharing options...
Decky Posted July 24, 2020 Share Posted July 24, 2020 When everything else fails: https://www.aliexpress.com/item/4000248609363.html?src=google&src=google&albch=shopping&acnt=494-037-6276&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shopping&aff_platform=google&aff_short_key=UneMJZVf&&albagn=888888&albcp=9604210690&albag=100463787298&trgt=296904913880&crea=en4000248609363&netw=u&device=c&albpg=296904913880&albpd=en4000248609363&gclid=Cj0KCQjwjer4BRCZARIsABK4QeUT8WVNZiBry3F8SugPWy5mlgIzNsRqNyA1yhuMeWC5zhyHqysIS1EaApIUEALw_wcB&gclsrc=aw.ds 1 Link to comment Share on other sites More sharing options...
audiofeline Posted July 30, 2020 Share Posted July 30, 2020 On 24/07/2020 at 6:33 PM, Decky said: When everything else fails: https://www.aliexpress.com/item/4000248609363.html?src=google&src=google&albch=shopping&acnt=494-037-6276&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shopping&aff_platform=google&aff_short_key=UneMJZVf&&albagn=888888&albcp=9604210690&albag=100463787298&trgt=296904913880&crea=en4000248609363&netw=u&device=c&albpg=296904913880&albpd=en4000248609363&gclid=Cj0KCQjwjer4BRCZARIsABK4QeUT8WVNZiBry3F8SugPWy5mlgIzNsRqNyA1yhuMeWC5zhyHqysIS1EaApIUEALw_wcB&gclsrc=aw.ds ... I'd love them to give the references to studies that show that connecting a plant to an electrical earth decreases stress anxiety and depression, reduces inflammation, slows aging, give better sleep, and improves cardiovascular health. I wouldn't expect much scientific rigour if they are able to produce any evidence. Link to comment Share on other sites More sharing options...
gwurb Posted August 1, 2020 Share Posted August 1, 2020 What is your amp (brand, model)? Rel sub model? I had to deal with a ground loop problem for my sub on high level input... Link to comment Share on other sites More sharing options...
Jhsg Posted August 1, 2020 Author Share Posted August 1, 2020 (edited) 37 minutes ago, gwurb said: What is your amp (brand, model)? Rel sub model? I had to deal with a ground loop problem for my sub on high level input... Hi mate the amp is a ps audio bhk250 and the sub is a is a rel t9i. Edited August 1, 2020 by Jhsg Link to comment Share on other sites More sharing options...
awayward Posted August 1, 2020 Share Posted August 1, 2020 10 minutes ago, Jhsg said: Hi mate the amp is a ps audio bhk250 and the sub is a is a rel t9i. Probably not much help but I have the same amp and sub, 2 in my case, I gave up on the hum and just turn the subs off when the BHK250 is in standby mode. 1 Link to comment Share on other sites More sharing options...
Jhsg Posted August 1, 2020 Author Share Posted August 1, 2020 3 minutes ago, awayward said: Probably not much help but I have the same amp and sub, 2 in my case, I gave up on the hum and just turn the subs off when the BHK250 is in standby mode. I’ve found 2 solutions. Possible Solutions I should say as I haven’t personally tried them yet. The first one is the arrow wireless kit for the sub. The second is a resistor network you can get for the sub. I’ve bought both and waiting for them to arrive. Will let you know how they go. Link to comment Share on other sites More sharing options...
gwurb Posted August 1, 2020 Share Posted August 1, 2020 11 minutes ago, Jhsg said: I’ve found 2 solutions. Possible Solutions I should say as I haven’t personally tried them yet. The first one is the arrow wireless kit for the sub. The second is a resistor network you can get for the sub. I’ve bought both and waiting for them to arrive. Will let you know how they go. Three more questions before I mention what I did. 1. You put the BHK250 into standby when you turn it off? You don't actually flick the rocker power switch to off? 2. Have you tried what the REL manual suggests with connecting the black cable to unused RCA? 3. Do you have a link for the resistor network that you bought? I am curious how similar it is to what I did for me. Link to comment Share on other sites More sharing options...
awayward Posted August 1, 2020 Share Posted August 1, 2020 22 minutes ago, Jhsg said: I’ve found 2 solutions. Possible Solutions I should say as I haven’t personally tried them yet. The first one is the arrow wireless kit for the sub. The second is a resistor network you can get for the sub. I’ve bought both and waiting for them to arrive. Will let you know how they go. That will be great, appreciated. Link to comment Share on other sites More sharing options...
Jhsg Posted August 1, 2020 Author Share Posted August 1, 2020 (edited) 12 minutes ago, gwurb said: Three more questions before I mention what I did. 1. You put the BHK250 into standby when you turn it off? You don't actually flick the rocker power switch to off? 2. Have you tried what the REL manual suggests with connecting the black cable to unused RCA? 3. Do you have a link for the resistor network that you bought? I am curious how similar it is to what I did for me. 1. Yep - always put it into standby first. 2. Tried putting the black wire everywhere - on an unused rca, phono ground on my AVR, AM ground on my AVR, Chasis of my AVR & chasis on other components. 3. See attached image for more info. If you pm me your email, I’ll forward you the full chain. The only thing I haven’t tried is running a wire from the chasis of the BHK to the AVR to see if I can get common ground between them. This is something ps audio suggested. Assume you’ve also seen / read through this: https://forum.psaudio.com/t/bhk-pre-and-power-on-the-way-rel-subwoofer-question/3662/143 Edited August 1, 2020 by Jhsg Link to comment Share on other sites More sharing options...
Jhsg Posted August 1, 2020 Author Share Posted August 1, 2020 I also got the earth kit from ps audio and installed it on the bhk250. It made zero difference. Link to comment Share on other sites More sharing options...
gwurb Posted August 2, 2020 Share Posted August 2, 2020 On 01/08/2020 at 11:38 AM, Jhsg said: 1. Yep - always put it into standby first. 2. Tried putting the black wire everywhere - on an unused rca, phono ground on my AVR, AM ground on my AVR, Chasis of my AVR & chasis on other components. 3. See attached image for more info. If you pm me your email, I’ll forward you the full chain. The only thing I haven’t tried is running a wire from the chasis of the BHK to the AVR to see if I can get common ground between them. This is something ps audio suggested. Assume you’ve also seen / read through this: https://forum.psaudio.com/t/bhk-pre-and-power-on-the-way-rel-subwoofer-question/3662/143 I had a skim through it. My amp and subwoofer are different. I had an issue with Marantz PM6006 and SVS PB1000. The only way to make the connection between PM6006 and PB1000 is via speaker level; in fact I had to downgrade from SB2000 as PM6006 has no low level output. In sorting out my hum problem the retailer was passing troubleshoot instructions from SVS engineer to me and I was relaying my findings. In the end we got to a solution. When I looked through the above thread here is what I would say: 1. You already paid for that resistor network so it may do the trick for you. 2. If you still want to try the method that I used then: Get a piece of wire that is long enough to run between the REL and the BHK Crimp down one end of the wire on the REL's ground screw Put the BHK into standby mode Touch the screws on the BHK case with the other end of the wire and see if the hum stops. Start with the following location. That post is an addition so it may have a longer screw than the screw itself. Then try the other screws that I highlight on the following image What I eventually did was solder a metal loop onto the end of a wire on the screw end, and a spade on the ground post end. I have the wire running between the two. It allows the subwoofer and amplifier grounds to be at the same potential. If you find that no matter what BHK screw you connect to the REL ground screw it makes no difference then you may need the screw replaced with a binding post, or as you have the ordered the resistor network it may do the trick anyway. I would be curious if my recommendation works for you. 1 Link to comment Share on other sites More sharing options...
gwurb Posted August 2, 2020 Share Posted August 2, 2020 Oops, missed two screws below the fuses Link to comment Share on other sites More sharing options...
Jhsg Posted August 2, 2020 Author Share Posted August 2, 2020 2 hours ago, gwurb said: I had a skim through it. My amp and subwoofer are different. I had an issue with Marantz PM6006 and SVS PB1000. The only way to make the connection between PM6006 and PB1000 is via speaker level; in fact I had to downgrade from SB2000 as PM6006 has no low level output. In sorting out my hum problem the retailer was passing troubleshoot instructions from SVS engineer to me and I was relaying my findings. In the end we got to a solution. When I looked through the above thread here is what I would say: 1. You already paid for that resistor network so it may do the trick for you. 2. If you still want to try the method that I used then: Get a piece of wire that is long enough to run between the REL and the BHK Crimp down one end of the wire on the REL's ground screw Put the BHK into standby mode Touch the screws on the BHK case with the other end of the wire and see if the hum stops. Start with the following location. That post is an addition so it may have a longer screw than the screw itself. Then try the other screws that I highlight on the following image What I eventually did was solder a metal loop onto the end of a wire on the screw end, and a spade on the ground post end. I have the wire running between the two. It allows the subwoofer and amplifier grounds to be at the same potential. If you find that no matter what BHK screw you connect to the REL ground screw it makes no difference then you may need the screw replaced with a binding post, or as you have the ordered the resistor network it may do the trick anyway. I would be curious if my recommendation works for you. Thanks mate. Appreciate the feedback. You got me excited and I tried your trick. No luck unfortunately. Link to comment Share on other sites More sharing options...
gwurb Posted August 2, 2020 Share Posted August 2, 2020 (edited) 10 minutes ago, Jhsg said: Thanks mate. Appreciate the feedback. You got me excited and I tried your trick. No luck unfortunately. One more thing to try if you are interested. That screw that is circled in green is the one that PS recommends replacing with a binding post. Remove that screw and make wire contact between the REL ground bolt and the nut of the removed screw. The reason I write that is that the current screws are most likely powder coated. From the PS Thread: "I received this from John at REL “PS has actually just this week released involving replacing an existing chassis bolt with a new one that has a knurled head allowing true earth ground for the chassis and hence no hum when the unit goes to sleep.”" If you are good with a multimeter then there are other things to try but it won't be needed if the resistor network is fine. Edited August 2, 2020 by gwurb Link to comment Share on other sites More sharing options...
Soundfever Posted August 9, 2020 Share Posted August 9, 2020 (edited) This is my setup and it doesn’t have any hum issue. I have 2 t9i subs. If you have one then maybe try red to right positive, Yellow to left positive, black to either negative. That was my setup before I got the second sub. Music : DSJ -xlr-Gain cell pre - xlr - Mark Levinson 532h HT : Marantz sr7012 - rca - gain cell pre. Sub1 out to Rel t9i (#1) LFE, Sub2 to Rel t9i (#2) LFE. ops, correction, bad memory. From ML532h - speaker cables to speakers. Speakon cable - Left positive - Red + yellow, Left negative - Black -> rel t9i (#1). Right positive - Red + yellow, right negative - black -> Rel t9i (#2) Dsj, gaincell, marantz 7012 on power circuit 1, ml532h circuit 2, subs circuit 3. Edited August 10, 2020 by Soundfever Link to comment Share on other sites More sharing options...
Jhsg Posted August 9, 2020 Author Share Posted August 9, 2020 3 minutes ago, Soundfever said: This is my setup and it doesn’t have any hum issue. I have 2 t9i subs. If you have one then maybe try red to right positive, Yellow to left positive, black to either negative. That was my setup before I got the second sub. Music : DSJ -xlr-Gain cell pre - xlr - Mark Levinson 532h HT : Marantz sr7012 - rca - gain cell pre. Sub1 out to Rel t9i (#1) LFE, Sub2 to Rel t9i (#2) LFE. From ML532h - speaker cables to speakers. Speakon cable - Left positive - Red, Left negative - Yellow + Black -> rel t9i (#1). Right positive - Red, right negative - yellow + black -> Rel t9i (#2) Dsj, gaincell, marantz 7012 on power circuit 1, ml532h circuit 2, subs circuit 3. Thanks mate but your amp is not the same as the BHK250. Main thing is the negative outputs on the BHK250 are not earth. Link to comment Share on other sites More sharing options...
Soundfever Posted August 9, 2020 Share Posted August 9, 2020 (edited) Arggg, have you try a rca cable from the gain cell input to the bhk250 input? Also, put a rca cable from the marantz avr sub out to the lfe Edited August 9, 2020 by Soundfever Link to comment Share on other sites More sharing options...
Jhsg Posted August 9, 2020 Author Share Posted August 9, 2020 2 minutes ago, Soundfever said: Arggg, have you try a rca cable from the gain cell input to the bhk250 input? Also, put a rca cable from the marantz avr sub out to the lfe Yep, I have a RCA from my Marantz 6014 to the T9i for .1 whilst using the setup for HT. Also tried buying the REL wireless kit (Arrow) which didnt work. Now I have a new REL wireless kit sitting around doing nothing. Based on everything I've read / tried, the fix for this is a wiring kit from REL which I have ordered. Problem is mail from the UK takes a few weeks at the moment. Link to comment Share on other sites More sharing options...
gwurb Posted August 9, 2020 Share Posted August 9, 2020 1 minute ago, Jhsg said: Yep, I have a RCA from my Marantz 6014 to the T9i for .1 whilst using the setup for HT. Also tried buying the REL wireless kit (Arrow) which didnt work. Now I have a new REL wireless kit sitting around doing nothing. Based on everything I've read / tried, the fix for this is a wiring kit from REL which I have ordered. Problem is mail from the UK takes a few weeks at the moment. You have your Rel making a noise with a wireless kit? When there is no wire connection between the Rel and any other amplifier? Link to comment Share on other sites More sharing options...
Soundfever Posted August 9, 2020 Share Posted August 9, 2020 (edited) From the psa forum(https://forum.psaudio.com/t/bhk-pre-and-power-on-the-way-rel-subwoofer-question/3662/18) “PS has actually just this week released involving replacing an existing chassis bolt with a new one that has a knurled head allowing true earth ground for the chassis and hence no hum when the unit goes to sleep.” upon further reading, the new bolt failed. Sorry to get your hopes up. Edited August 10, 2020 by Soundfever Link to comment Share on other sites More sharing options...
Jhsg Posted August 10, 2020 Author Share Posted August 10, 2020 9 minutes ago, Soundfever said: From the psa forum(https://forum.psaudio.com/t/bhk-pre-and-power-on-the-way-rel-subwoofer-question/3662/18) “PS has actually just this week released involving replacing an existing chassis bolt with a new one that has a knurled head allowing true earth ground for the chassis and hence no hum when the unit goes to sleep.” upon further reading, the new bolt failed. Sorry to get your hopes up. That was back in 2017. It hasnt been a successful fix. I got the part from PS Audio and it didnt work for me. The REL fix is the go. 1 Link to comment Share on other sites More sharing options...
Soundfever Posted August 10, 2020 Share Posted August 10, 2020 Is the Rel wireless kit expensive? I might get one for the subs at the back of the room. Link to comment Share on other sites More sharing options...
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