My S750 went, looking at my options.

ellover009

[H]ard|Gawd
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Long story short is we had power loss the other day, and when the power came back the control panel was dead on the Cambridge sound works S750, and I tried to cycle the power on the sub and saw the green light flashing. I took it apart and found what looks to be glue and at least 1 main capacitor that didn't look great and a questionable part on one of the boards. I had the system for at least a decade, and I found it to be fine, Not as nice as the surround system on my tv thou.
My options are

1) use the old repair guide someone put up and try to source capacitors and learn to solder, the guide is old and a lot of the capacitor options are different from when the guide was made.
2. Hope klipsch restocks one day the pro-media 2.1 thx.
3. pick up a jbl 306P MkII and rig it up, its on sale now, but nowhere near as good price as a few weeks ago. Id love to get them at the price from 2 weeks or so ago, but using the 2w sound from the computer screen is miserable.
4. Insert ideas here, lol.
5. Find a way to temporarily rig up at least 2 of the S750 speakers.

Right now I am using the built in sound card from my crosshair VII hero, used to have a creative labs zx2 plat, but it didn't fit in with the 2 slot video card since its a full size pci card, and it got damaged outside.

I haven't had time to mess around with the sub recently due to classes. Semester is finishing up.

This is what it looks like inside the S750.
https://imgur.com/a/bKDkcvs

This is the repair guide I found from 2013
https://forum.lowyat.net/topic/2873...RKac2JXyHkwsAzQYnb8ngRpB4iCvYI9U_NsqFB7Ez5UAU

My only concern if I go with the JBL is that I might have to wait a bit on adding a subwoofer if I go that path due to cost. I also live in an apartment and can't have the sub at full capacity at all times.
I use a P300HD on my tv surround system and that thing is amazing, none of that rattling nonsense. Too bad there's nothing similar and smaller and a reasonable price.
 
Depending on what you're coming from, this may be moot, but I would point out that studio monitors in general are very large. If possible, I'd recommend sticking with the 5" variants and using a separate sub as opposed to grabbing larger monitors to extend the low-end.


For reference, I run a pair of the older LSR305 monitors with a cheap Rockwille 10" sub (might recommend doing better than this, but the thing works), with the audio chain being:

Onboard optical out --> Topping DX7s balanced DAC/Amp XLR output --> Nobsound passive pre-amp with switchable XLR / RCA -->
  • XLR --> Rockville 10" sub XLR --> LSR305 pair
  • RCA --> Massdrop Cavelli Tube Hybrid (CTH) headphone amp --> whichever cans I'm using at the moment

Input is a Blue Snowball

Notable points:
  • Using an almost completely balanced chain to eliminate interference noise potential; it's something I've dealt with in the past, and when spending some change on audio, something I wanted to avoid by design
  • Optical output is to eliminate the possibility of a ground loop, as can be had with USB amps
  • Tube amp is for 'brighter' cans, such as my DT880s and HE4XX
  • Nobsound pre-amp provides global volume control and analog switching between speakers and headphone amp -- very convenient and very quick for the purpose
 
Also no headphone recommendations, I have some audio technica ATH-A900LTD, and they are great, but summer's coming, and I rather use speakers.
 
Two things:

Your S750's are consumer electronics that while repairable, likely won't stay 'repaired'. I could certainly be wrong here, and repairing the set is likely the cheapest option, but you have no guarantee that said repair would be effective nor that it would last.

The JBL monitors have a range of input options, and given that they're powered, you need only a 3.5mm stereo to 6.3mm mono splitter to hook them up to your onboard audio. While there may be limitations with this setup, you could at least get them going for very little investment beyond the monitors themselves. And as you don't necessary want / need a subwoofer, you can just get a pair of the 6" monitors and largely be done with it.

Beyond that, in my post which you quoted above, there are further possibilities for refinement if you run into issues. Also with respect to headphones, you might consider an inexpensive set of open or semi-open headphones if the issue you're encountering is heat or sweat buildup with the closed ATH's.
 
Pick up some cheap receiver off of craigslist. You could upgrade the fronts and keep the satellites as rears/surrounds.
 
i think I wanna avoid getting a receiver, too large, and unnecessary hookups. Lots of waste.

That and, realistically, you just need an amp.

However
, getting seven channels amped up (assuming that the sub / amp is 'done') is easiest, cheapest and least space consuming using a receiver. There are a lot of functions on a receiver that you simply won't use, but at the same time, there aren't really options for amplifying that many channels with something smaller and cheaper than a receiver.

Add cheap / used ~8" sub and roll out, and you can upgrade speakers at will.
 
For the PC I went down to 5.1 from 7.1, I think I could live with 2.1. but I am surprised that 3.1 aren't more popular, center speaker for clarity. Don't have the space anymore to run full 7.1, I already have a decent surround system on the tv.
 
Center speaker is more for side listeners in a home theater, for PC it's not necessary. 2.1 should be more clear than 3.1 because the vocals are coming out of 2 speakers.
 
Yup. The center channel exists entirely because that's where stage-front spoken dialog is mixed to. It's a necessity in a home theater, I've found; while I have 7.1.2 set up right now, I'm quite happy with 3.1 when in a limited environment, but no less.

On the PC, it just isn't needed. pippenainteasy is right here. So long as your PC sound is being fed from a PC, you're good with just stereo. Even for surround stuff.

My current setup (detailed in your quote) is absolutely usable for all media types, even without the sub. Just straight 2.0. Most important is where you place the monitors / speakers. Get that right and the rest falls into place.
 
ah. lol. for the home theather I went with the biggest I could cram under the tv at the time. stand. It was either MC300s or 400s. M80s side, P300HD sub, and 2 curbed surround speakers for back. I miss Cambridge Sound Works, you could pick up some nice stuff when there was things on sale. Idea back then was that a large center speaker would have less distortion, better clarity. I didn't know that it wasn't the ideal situation for a desktop use.

Now here's an interesting question. Why do some of the pre-amps, audio interface ect, connect to the PC via USB? wouldn't it be more ideal if it wasn't taxing the USB drives, or use it's own dedicated line?
 
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I fixed my S750 by replacing the capacitors on the powerplane and also replacing the glue with high temp acid free silicone glue.
Cost me less than $50 in materials.

They don't make any PC speakers (7.1) that come anywhere close to these.
If you don't know how to solder yourself, it's an easy repair for a shop.
 
I fixed my S750 by replacing the capacitors on the powerplane and also replacing the glue with high temp acid free silicone glue.
Cost me less than $50 in materials.

They don't make any PC speakers (7.1) that come anywhere close to these.
If you don't know how to solder yourself, it's an easy repair for a shop.

How long ago was that? Was the thing caked with the burnt out glue like my images?
I know they don't make some things like this anymore, shoot, Cambridge sound works doesen't really exist anymore since they got sold to I think a Chinese company, all they have at their site are some wireless pod speakers, nothing else.

The one thing that discourages me a bit is that in the repair guide they talk about all the capacitors and such, the numbers have changed over time, but the big thing is this image.
https://imgur.com/4xVgu1W
The stuff circled looks pretty bad. Anyone know if that looks off, and what is that?
 
Just ordered the speakers today. Now to figure out how to hook up this sorcery.
I was tempted to go with the 308, but they might be a little "rolls eyes" on the big side.

I am thinking either this would work
https://www.amazon.com/gp/product/B...5ef2768d11e98f1d7a1b1e43ba390INT&ie=UTF8&th=1
or

https://www.amazon.com/Devinal-Y-Ad...=2661617011&s=gateway&sr=8-23#customerReviews
https://www.amazon.com/TISINO-Stere...2:2661618011&rnid=2661617011&s=gateway&sr=8-6
What I noticed from a lot of these is that they list as going from 1 balanced to 2 unbalanced since the signal is split. So I am assuming that the only way to balance it is a pre-amp, but then you still have the splitting cable issues inputting into the device. My other assumption is whatever I use avoid optical out since it usually does a signal pass through, and bypass the sound-card processing.

I'm tempted to look at some of the pre-amps things, the problem is, is there something good that's sensibly priced? Is there any benefits of going with a USB one? I've seen re-commendations of people going with an USB one. I would think its worse because you are adding load to part of a pc that already has a dedicated ports, otherwise sound cards would have a usb port built in or you'd still have fire-wire ports.
 
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This one.

My other assumption is whatever I use avoid optical out since it usually does a signal pass through, and bypass the sound-card processing.

It can, but that's a driver level thing. You can use say Razer's app to do pre-output processing such as EQ. Further, 'sound-card processing' is just software modifying audio. With respect to reference monitors, you mostly don't want to do that; you're already hearing almost exactly what was intended.

I'm tempted to look at some of the pre-amps things, the problem is, is there something good that's sensibly priced? Is there any benefits of going with a USB one? I've seen re-commendations of people going with an USB one. I would think its worse because you are adding load to part of a pc that already has a dedicated ports, otherwise sound cards would have a usb port built in or you'd still have fire-wire ports.

Mostly: no. What you're talking about is a USB DAC, which isn't really a pre-amp except that it obviously has to output some signal.

With respect to 'processing load', it's largely irrelevent, and further, it's all done in software regardless. There is no more 'hardware audio'. Microsoft ripped it out.

At best, optical combines a digital signal output while using the PCIe bus on your motherboard (to integrated audio or a sound card) which is a lower latency and processing load than USB, but it seriously doesn't make a difference to user experience. Optical's main advantage is breaking the potential for a ground loop that can happen with USB.
 
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Bought the JBL, the cable, and the groundloop. Everything is fine, there is no regret of going with this. The only thing is that it takes a few days to get used to this, there's fatigue during the first few days, and then I got used to this, don't know if it's because in my old job used to be noisy so I had developed a skill that lets me tune things out, and it require time to train my hearing to voices, and frequencies. The S 750 was great for it's time, but it's time to move on. I picked the JBL on sale, but it wasn't at it's all time low, I guess the poor have to pay twice, lol.
 
My only big complaint is the glossy plastic. It's a dust magnet.
 

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How long ago was that? Was the thing caked with the burnt out glue like my images?
I know they don't make some things like this anymore, shoot, Cambridge sound works doesen't really exist anymore since they got sold to I think a Chinese company, all they have at their site are some wireless pod speakers, nothing else.

The one thing that discourages me a bit is that in the repair guide they talk about all the capacitors and such, the numbers have changed over time, but the big thing is this image.

The stuff circled looks pretty bad. Anyone know if that looks off, and what is that?


Sorry, I forgot to reply...your picture looks fine...it just looks like solder flux.
 
My only big complaint is the glossy plastic. It's a dust magnet.

That's literally the only complaint about these for the price. It's also inexplicable on JBL's part and they've definitely been ribbed by reviewers for it.

I'll keep my matte white set for now ;).
 
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