out of desperation I turn to my fellow Yamaha owners!

does anyone know where in Melbourne I can either BUY or HAVE MADE the following cable.

I need a TRS cable (1/4inch to 1/4inch, balanced) on which I can unscrew the jack so that I can lift the earth shield on one of the jacks. This is just so that I can overcome a ground loop problem between my S90 and my Souncard (C-Port). Its a simple request but no-one in Melbourne seems to sell TRS cables with screwable jacks (everyone has the moulded plastic covering), and no-one seems to want make the cables up for me!

I’ve already tried most of the music stores, and some of them have looked on their catalogues and found no TRS cables with screwable jacks. I’ve also tried TANDY’s and JB-HIFI, and JAYCAR - no luck.

If anyone has any suggestions please let me know!
I feel like I’m living in a country town!

PS: please don’t write back suggesting that I get myself a soldering iron and do it myself!!

Thanks,
Jordan

Re: Melbourne: does anyone make cables in this city!?!

Get a soldering iron and..... oops! I just re-read your post.

Your best bet in Melbourne would be to get in touch with a place that does repair work for the music shops. You could try the yellow pages or just ask the music stores. I’m surprised they didn’t suggest this themselves. Better still is if they do P.A. system work/repairs. It’s possible that they might charge a lot because it’s a relatively small job that they would otherwise not bother with.

A guy in Wodonga that runs a studio/PA hire/sales business made up a whole bunch of leads to order for us one time no problems. I guess us country folk are a little more self-sufficient :-)

Otherwise let me know how long you need the (2?) cables and if you’re stuck I can make them up and send them C.O.D. I have the wiring diagram for the exact cable you’re after in the excellent manual for my mixer. I think the outputs of the keyboard are unbalanced so I’m assuming the C-Port jacks are balanced. If so the end with screen earthed will plug in there. Is that the setup you’ve got?

I’ll take a look in Dick Smith today (Friday) and get an idea of the price for the cable and plugs. Last time I looked they had all the necessary bits. Either way I’ll repost here later today with the cost for parts so you’ll know if anyone else you might find there is overcharging.

- Wayne

Re: Melbourne: does anyone make cables in this city!?!

wow!

...and just when i was beginning to lose hope. I think you country folk just have more time to give each other good advice!

The S90 has unbalanced outputs. The C-Port has two balanced inputs and 8 unbalanced inputs. I would be plugging the S90 into two of the unbalanced inputs. It has been suggested that I use TRS cables for this connection.

The cables (2 of them) need be no longer that 1 meter each. 1.0 meter would be perfect.

I’ll check your next post with info on cost! Thanks, Wayne…


Jordan

Re: Melbourne: does anyone make cables in this city!?!

I assumed you were talking about going into balanced inputs. That’s where the cable we’re talking about is a fairly standard possible soution. If you’re using unbalanced at both ends then you’re likely to get the same result as with the regular instrument cables. Depending on how the C-Port’s unbalanced in’s treat a TRS plug you either get ;

1)The shield connected to the negative signal conductor, ground loop still intact.

2)The shield connected instead of the negative signal conductor, meaning that with the shield lifted at the other end there’s no ground loop but also no signal.

3)The positive and negative signal wires connected but the shield not connected at either end, which ends up being the same as a regular unbalanced cable (and again with the ground loop intact).

Since I’ve just come off 5 months night shift I might be missing something (apart from sleep, social life and brain function), but my mixer manual tips and diagrams seem to be referring to how to deal with unbalanced at one end and balanced at the other.

Parts for two of the afore-mentioned 1.5 metre leads comes to about $12 or so.

What is using the two balanced inputs on the C-Port? Does it or your PC motherboard have a digital input you could try from the keyboard’s digital out? You could look for a PCI card that has one too. I suspect we might have to look a a few options depending on the answers to these questions.

- Wayne

Re: Melbourne: does anyone make cables in this city!?!

Hi, Wayne,

thanks for your detailed reply…

So what you are saying is that it is superfluous for me to use TRS cables for this connection? A friend had previously suggested that I simply lift the earth shield at one side of the interconnecting cable to get rid of the ground loop. For my purposes he said it didn’t matter which side. but he hadn’t specified whether the cable he was talking about was balanced or unbalanced.

I keep aside the two balanced inputs on the C-Port for guitar and microphone: things that need the preamped inputs. The C-Port has a daughter PCI card that supports digital in, which I do not use. Do you suggest that I go digital from the keyboard to the computer, instead of my present setup?

Thanks for your help! I will do some homework and hopefully give you more info…

Jordan

Re: Melbourne: does anyone make cables in this city!?!

Going for the digital connection would be another good option if the connections are compatible. You get benefits in terms of overall sound quality too. I would assume the C-Port software shows it’s digital connection along with the analog ins.

We’ll figure it out one way or another.

Re: Melbourne: does anyone make cables in this city!?!

Jordan, by now you may have solved your problem, but here is my 2 cents worth: According to Yamaha the 1/4 in.  outputs on the Motif 6 ( for example since I just bought one) are unbalanced and therefore would not be enhanced by using balanced (TRS) cables or connections. My new dig. 24 track is a different story. Its’ 1/4 in. ins and outs are indeed balanced(for trs or xlr) and , believe me, the trs connections make a world of difference with monitors etc. Both of these do have the digital connections (motif comes with dig. optical out) so, I guess digital is the way to go in my case and probably in yours. We can generalize and assume that most synths. nowadays offer only unbalanced analog connections like most guitars. So, either connect digitally or convert unbalanced to balanced with a Direct Box or line level shifter. Personally if I have to buy something else to quiet down my connections, digital seems the place to spend the money. Digital is quiet as doom....... T.

Re: Melbourne: does anyone make cables in this city!?!

Thanks Wayne and Timo, and merry xmas ‘nall while we’re at it!

i think the digital option is the best solution… but not for me, because the S90 doesn’t seem to have digital outputs! so i’m stuck in analog-land!

given the unbalanced-to-unbalanced connection i’m making, the TRS cables wouldn’t enhance the sound in any way, but for my purposes I thought they would be useful since they have an earth cable that can be lifted, thus getting rid of the ground loop noise. This is what I had been advised to do: lift the earth on the interconnecting cable (which must be TRS if it has an earth signal). I’m no longer sure if this is possible, from Wayne’s description. is it?

I’ve also started to wonder why I’m getting this ground loop in the first place. I’ve tried different AC outlets in the house. Could it be a problem with the S90?

The DI BOX solution seems to be the other alternative. But a guy at a music store who owns a Motif said that when he tried to go analog he got the ground loop even with the DI and the earth switch lifted. I may have to give it a try.

Thanks always for your advice!! really hope you have more of it!
Jordan

Re: Melbourne: does anyone make cables in this city!?!

I assumed you would have tried this already but just in case-

Have you run all the mains powered gear that is connected from the same power point? That’s the first thing anyone you spoke to should have suggested.

The sticking point with your situation seems to be the loop being carried by one of the conductors when using unbalanced connections at both ends. As above, any way you dice it with the leads you still have the same situation except where the lead doesn’t work at all. Other than that, without actually being there I’m pretty well stumped.

If there’s something we’ve missed or whoopsed maybe someone will jump in and bring it to our attention. I haven’t had to deal with this problem myself for a long time.

Re: Melbourne: does anyone make cables in this city!?!

hi, Wayne,

thanks. i did try what you suggested a while ago and still got the noise: i just tried plugging the keyboard in the same board as the computer, 2 make sure again, and its still there.

weird thing is that I even get this noise when i have the USB cable connected to the computer.

the only way i can make the noise go away is by using an expansion board that has the earth pin removed. for obvious reasons i’m only using this as a temporary reference for what its supposed to sound like. however, even when i have this earth-lift on the power-cable to the S90 and I plug in the USB cable the ground loop returns!! can it be coming from the computer in the first place?

a lot of people have suggested the DI, and I’ve been reluctant because the soundcard only takes unbalanced inputs. however, if that’s the only thing that’s going to work i may just have to give it a try.

do you think there could be a fault with the actual keyboard?

Re: Melbourne: does anyone make cables in this city!?!

Hi again Jordan, more thoughts on cables, line noise etc. Whether balanced or not all cables are not equal. You will have noticed this if you have priced them. Some expensive cables are really better. Good shielding and thoughtful design and quality makes good cables quieter.It’s not just a trick to make more money. I like “Monster Cables” Interconnect Series.(no affiliation, I promise). They fixed my noise ridden studio monitors instantly. XLR to TRS cables and as short as possible.(1 meter). The pair cost $40. from Same Day Music usa............ Also, you might want to explore the possibility of noise being introduced from another source into your line current. Plug into different outlets, turn off an old amp, and if need be look into filtering devices that might clean up your house current. We’ve all got our digital electronic gear plugged into the same circuitry as washing machines and these noisy transformers that every device(under $300.) uses nowadays. Put on your earphones with noise and go about unplugging devices and you just might find a “Devil” !  But then , What do I know.?  Have a good year, Timo.

Re: Melbourne: does anyone make cables in this city!?!

hi Timo,

hope you had a good new year! thanks for your post. I am using fairly good cables (HOSA) for the connection and the noise does not increase when i use inferior cables. I have tried unplugging every single appliance in the house but that does not change the problem! I have tried using a DI box with the earth lift and that solves the issue but when i connect the S90 to computer via USB cable, the noise returns! Just as an experiment I have run the setup with both computer and keyboard unearthed and the noise is STILL there which makes me think there is no interference from other applicances in the house. it might be something other than an earth loop therefore. At the moment I have resigned myself to running the setup in the only way in which it works silently: with the DI and without the USB connection. Two problems with this: I think the sound quality is reduced by using the DI as the levels peak much more easily even though the it should still be outputting at 0db. Secondly, I have just been reading in the S90 manual that the USB connection allows you to handle more MIDI ports and polyphony that the normal MIDI cables.

(sigh)

Thanks,
Jordan

Re: Melbourne: does anyone make cables in this city!?!

Try using the Midi connection and see if it does the job well enough for how you’re working. The Midi connection is optically isolated so it doesn’t make an electrical earth connection. It sounds like the USB connection is at least part of the problem.

Have you tried the Midi connection along with the straight audio cables?

Your PC might be letting some crud through to the soundcard and/or USB port. Even though using a breakout box gets the converters away from inside the PC if the power to it and the USB ports is dirty you can get problems. I plugged in some small USB powered speakers to my old PC and I could hear the modem, processor hard drive etc. ie. any electrical or RF goings on came through along with a steady noise that was unaffected by even turning the volume all the way down. That made me think the power to the USB wasn’t very smooth. On my new PC they were much quieter. That would most likely come down to the motherboard in the PC, maybe also partnered with a so-so or overworked power supply. In that case the PC could be the crux of problem.

Since you don’t need the power from the USB connection (I don’t think), you could try lifting the two connections on the USB cable that carry the power and see if that lets you keep the USB connection. I think it’s the two outer ones but it’s a while since I looked. I wouldn’t hold my breath but it would be easy to try out.

Re: Melbourne: does anyone make cables in this city!?!

Hi Wayne, thanks for your post,

so far the MIDI connection does the job I need it to. The Midi cables with the straight audio connections generates the noise. I have gotten rid of this by using a Di box, but I have decided not to use this because it seems to me that the DI affects the quality of the sound (it peaks more easily). so I am simply using an unearthed expansion board to feed the power to the S90. This gets rid of the noise and does not affect the quality of the sound. This is not how I would like to resolve the issue ideally, but it has to do until I can find a better solution. In any case it is not a fool-proof solution because when I add the USB connection the noise returns! I tried a new, top of the line USB cable just in case I had a faulty one.... no luck. so be it, as I said, the MIDI cables do the job, for now. 

What you say about the computer maybe being the problem does make me wonder about it. However, I don’t get any noise when I simply listen to music through my soundcard and speakers (not like what you mention about when you plugged in those USB speakers). The noise is ONLY present when the S90 is involved in the picture. Surely if there were a problem with motherboard/power supply I would be hearing the noise from the momemnt I turned just the computer and speakers on.