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Computer - software / impedance matching

fuzzyboy, modified 7 Years ago.

Computer - software / impedance matching

Youngling Posts: 19 Join Date: 10/3/11 Recent Posts
I have a couple of questions regarding connecting the 8240's (two - stereo setup) to my PC.

As I understand it, the speakers require two connections to the PC - one for the sound control / GLM software, and one for the audio signal. The GLM software uses a box supplied in the software package that connects using a USB cable.

The audio signal input on the speakers is digital xlr (aes / ebu), which means that connecting to the PC require a transport (to do impendance matching) or a cable converter (and let the speakers to the matching).

1) So my question is - if I choose the latter - cheaper - option, will the quality of the audio signal be degraded compared to the transport option?

2) Also I've been reading about the GLM and GLM.SE software packages. The retailer I was talking to offered the GLM.SE software package - but from the Genelec webpage it seems that the GLM.SE is for use in a SE7261/8130A system? Will the GLM.SE package work with the 8240's? And what's the difference between the two software packages?

"The GLM.SE™ - Genelec Loudspeaker Manager for Small Environments - is a loudspeaker control networking system that offers capability to control all system parameters of a SE7261A subwoofer combined with Genelec 8130A active monitors."

Kind regards,
FB
1038, modified 7 Years ago.

Re: Computer - software / impedance matching

Jedi Master Posts: 339 Join Date: 4/6/09 Recent Posts
Hi fuzzyboy,

I assume when you are saying transport you mean transformer? I have setup many Genelec DSP sytems and have utilised many if not all of the available options of getting signal into them.

I have successfully used a S/PDIF (RCA) output of a CD transport, simply using a RCA-XLR cable, i have used USB soundcards that have AES/EBU outputs. The Genelec input is robust enough to accept the 75 Ohm signal, one note is that i made sure that the RCA-XLR cable was as short as possible, less than 2 Metres. If you need to run a cable longer than that i would recommend sticking to an AES signal.

You are correct about the GLM, the 8240's require GLM and not the .SE version

Good luck, once you have the system up and running you will love it.
clearsignal, modified 10 Months ago.

RE: Re: Computer - software / impedance matching

Padawan Posts: 35 Join Date: 3/2/18 Recent Posts

A while ago, Genelec informed me their monitors would be happy take in both 75 ohm and 110 ohm, SPDIF or AES (the difference between the formats is only a self-identifying bit that Genelec ignores).

As 1038 wrote, unbalanced cable should be short, lest interference is picked up. In any other regard, there’s no difference in sound between balanced and single ended cables.

 


You’ve mentioned Mutec as intermediary. From my experience, you’ll get better sound if you go computer USB to a SPDIF or AES converter. It usually re-clocks the signal and eliminates jitter. I’ve checked a few. The best and most economical is Schiit Eitr @ $179. Beats the Mutec MC 3+ @ $1,100…

You can then use a coax RCA -> XLR cable into your Genetec.
If you’re stickler like me and want to bump up to 110 ohm, you can get a Nuetirk impedance converter or a Funk cable.

 

fuzzyboy, modified 7 Years ago.

Re: Computer - software / impedance matching

Youngling Posts: 19 Join Date: 10/3/11 Recent Posts
Hi fuzzyboy,

I assume when you are saying transport you mean transformer? I have setup many Genelec DSP sytems and have utilised many if not all of the available options of getting signal into them.

I have successfully used a S/PDIF (RCA) output of a CD transport, simply using a RCA-XLR cable, i have used USB soundcards that have AES/EBU outputs. The Genelec input is robust enough to accept the 75 Ohm signal, one note is that i made sure that the RCA-XLR cable was as short as possible, less than 2 Metres. If you need to run a cable longer than that i would recommend sticking to an AES signal.

You are correct about the GLM, the 8240's require GLM and not the .SE version

Good luck, once you have the system up and running you will love it.


Ok, thanks for the info :)

Regarding the 75 ohm signal, I'm wondering if the sound quality willl be affected? Lets assume that option A is a 75 ohm signal directly from the PC to the speaker input and option B is is a 75 ohm signal from the PC to a Mutec MC-1 (or similar), which transforms the signal to 110 ohm and then from the Mutec to the speaker. Assuming the cable connecting the PC to the speaker (A) and the cable connecting the PC to the Mutec (B) is the same lenght, will the resulting sound quality be the same?
1038, modified 7 Years ago.

Re: Computer - software / impedance matching

Jedi Master Posts: 339 Join Date: 4/6/09 Recent Posts
I have used both methods, but i have never stopped to A/B them.

I don't have any hesitiation on using the 75 Ohm solution, but no doubt the 110 Ohm would be the preffered option, i suppose it all comes down to weighing up the potential audio costs associated with more devices and connections between the sorce and speakers V the impedance mismatch.

Sorry i couldn't give you a definitive answer.
emnipetro, modified 10 Months ago.

RE: Computer - software / impedance matching

Youngling Posts: 1 Join Date: 9/17/18 Recent Posts
I have seen them and asking the same question about computer software impedance network. I impedance matching network has used all kind of PF circuit. which reduces the reflection and increase the power supply. I have an hp computer that also occurs the same issue that the time I contact hp support provider and they resolve my issue. you can also contact them if you face that type of issue.