Can you get inline rj45 sockets?

[MikeHunt79]

I really need some, solder or crimp I don't care as I can do both...

I've only found wallmount sockets so far... surely there has to be in line sockets also?

 

[MikeHunt79]

I'd rather not use a joiner.. I'm sending audio down ethernet cables, so the less connections the better...

 

[MikeHunt79]

You really don't want to do this if you want good quality audio. Although good quality Cat 5 cable has a low inductance design, its capacitance is very high. This isn't such a factor as far as sonics go, but it will cause an unstable amplifier to oscillate which is bad m'kay.

IF you really really need to do this, you may need to create a Zobel network for your speakers.

Also, how much power are you sending down that cat 5? Its only 24awg so for a decent setup, you would be using 4 lots of cat 5 unless you are running a long length, in which case you would need more. You also need to use each pair as a + and -

What application is this being used for? In the home?

Car. I'm going to use shielded cat 5 and I intend to connect the shield to the cars ground somehow. I should have said sooner that this won't be speaker cable, but interconnect cable.

Basically, I've made a DIY car amp, and there isn't enough room on the end of the amp for 4 x RCA sockets, so I intend to fit an ethernet socket on the amp instead. This will be for pre-amplified signals, at a high impedance (more than 10k ohms), so would the capacitance still be a problem? As it's low power, I intend to one channel on each twisted pair, giving me 4 channels. Also, I think my amp already has a zobel resistor and cap as it's class D and it's needed to filter out the switching frequencies > 100kHz, but I'm not 100% sure on this.

I'm tempted to butcher an old ethernet card for it's socket, but if I could get an inline or chassis mount socket it would be far less hassle.

 

[MikeHunt79]

When you say Diy car amp, have you stripped the innards from another amp and made a case or soldered together bits from ******s bargain bin?

A bit of both... Got an old crappy car amp, and used the SMPS from it to power a fairly decent class D tripath module. Pics in this thread:

http://forums.overclockers.co.uk/showthread.php?t=17829129

The sound is good even tho I've only tested it briefly in the house with a small SLA battery. The module I've used is pretty much identical to the 41hz.com AMP9 kit and has no high level in...

A pre-amplified input such as the high level out of your head unit?

The plan is:
Pre-amp from headunit > active crossover > cat5 > pre-amp in on amp 9

So pre-amped basically, no high level outs being used.

Im assuming you are running subwoofers if you are running class D. To be honest, you need to really filter out anything below 200hz, which should be done on the amp.

Almost, it's a 4 channel module, so channels 3 & 4 are for 2 subs, and channels 1 & 2 are L & R up front.

As for the crossover, I'm waiting on some TL072 opamps, once these arrive I'm going for this circuit http://sound.westhost.com/project09.htm with a crossover point of 112Hz.

I think you would only be able to put 40 - 50 wrms down each pair and you would have to use 2 pairs for each channel. Also, if you do do this, I would just watch the heat on the amp, if you notice it getting hot, you have too thin a wiring.

Having spent 2 hours researching this, there are as many supporters as detractors from using Cat5 in audio, so the old phrase YMMV applies. Personally, I would use Molex connectors if I was doing this.

I want something compact with lots of connections, hence cat5... I could go with molex tho, I guess I'd need 2 x 4 pin connectors for 4 channels, which I may just be able to squeeze in...

FWIW, This amp will only do around 50Wrms with 0.1%THD, but this should be plenty for me really... I'm using stranded mains cable rated for 20A as speaker wire, and it works for me...

 

[MikeHunt79]

I like ghetto (and DIY). I learned quite a bit when doing this project... mainly stuff about op-amps and SMPS.

I've given up with the cat 5 idea, and just used RCA connectors in the end... It's easier, and I think they are more robust which is what I need for the car... I've tested it out and it works really well. I only tried some sine waves thru the sub tho as I have no crossover. It goes a lot louder than I thought it would...

I'm already using this Class-D amp module for my home stereo, and was really impressed with it, so I thought I'd get one for the car also... It's just kind of gone on from there really...

Class D has come a long way. Have a look at the newer tripath amps (the reviews and spec), and you will see that it is more than enough for full range. Some people prefer them over class A. Some people call them class T but that just makes thing more confusing IMO....

I'll keep you updated... Once everything is done I'll make a thread over at the sound city section.

EDIT: This is very close to the module I'm using... http://41hz.com/main.aspx?pageID=130 info: http://www.tnt-audio.com/ampli/autocostruire_mc4x100_e.html