Jon Weaver, JS Box vs Syncblaster



Hi Jon,

I noticed in another thread you have got your JS box. How does it compare to the syncblaster cable? do you get the same problems you had with the Syncblaster?


Jon Weaver

Distinguished Member
I only got around to installing my JS box at the weekend so havn't had too much chance to test.

To date, I have had the following 'RGB' connections to my Plasma

1. SyncBlaster
2. Home Made RGB+CVSB lead using the cheapest cable/connectors possible
3. JS Tech box.

In terms of picture quality, I have to say that they are all EXACTLY the same.. I couldn't see any difference between my 'home made' cable and the SyncBlaster before it went back, and I can't see any improvement between my 'home made' cable and the JS box (connected with IXOS SCART and Iiyama VGA cables).

However, as you will have read, when I had the SyncBlaster connected, the picture used to 'jump' occasionally.

I never proved whether this problem was caused by the SyncBlaster or not, but the JS box and 'home made' cable do not do this.

The other problem with the SyncBlaster is that it doesn't pass audio. So, if you are using the sound capability of of the Plasma and don't have any audio outputs free on your box, this might be a problem.

In terms of value, there is no doubting that my 'home made' cable did an outstanding job. It cost about £1 and worked perfectly.. BUT.. It used up the 'composite' input which ment that my VCR couldn't be connected.

The SyncBlaster is OK, but in light of the odd problem I had, it would be wise to pay the extra and go for the JS box.

I hope that this helps, but if you have any specific questions, you know where I am

All the best



Hi Jon,

Thanks for the reply. So you are telling me there is no difference in picture quality between a 'composite' and RGB->VGA connection.

Damn, why have I spent all this money:(

Jon Weaver

Distinguished Member
No no no.. Composite video is sh*t!

All 3 connections that I have used are RGB!.

The JS box and the Sync blaster convert RGB+Composite Sync to RGB+Horizontal/Vercital sync. All they are effectivly doing is taking the standard sync output of the device and splitting them into 'horizontal' and 'verctical' sync which is needed on the VGA or RGB+HV inputs.

The cable that I made up puts the RGB signals into the RGB/Component inputs and puts Composite sync into the Composite video input (Just for sync). But the picture elements are still RGB.

The only problem with this method is that it uses up the Component and Composite inputs.. So, if you have a requirement for either of these inputs (i.e for a VCR or DVD player), then you are stuffed.

But, if you are just going to use one input on your Plamsa, then, to be honest, there is no need to buy any kind of converted..

Infact, for the amount that I have used the VCR, I could have lived with my home-made cable for the forseable future.. Problem is that it uses the 'component' input too, so a connecting Progressive Scan device would not be possible. If you are happy with this, then all you need is a SCART to RGB+Comp cable and set the Plasma up to "Sync on Composite". No conversion is necessary.

But to answer your quesion. RGB is infinitely better than Composite, so buying a 'converter' is the right move.

I hope this helps


Hi Jon,

Apologies for the confusion, because you mentioned it using up the 'composite' I made the assumption that it was a composite cable you were using rather than the sync coming in on the 'composite' along with Components.:blush:



I went for the JS box (RGB-VGA), haven't tried it yet as I need to wait to move into my new house in January (hopefully). So hopefully all will be working well when I get it set up.

Wish January would hurry up though:rolleyes:


Previously Liam @ Prog AV
If you're gonna use RGB with Sync on composite then a little bit of cunning will actually let you use your VCR as well!

Seeing as the Sync is down composite you can actually use the composite video input or the RGB input to view whatever is going down the scart cable.

So by daisy chaining or using a scart switcher for all of your devices, you are able to select RGB input to watch the RGB ones, and composite video input to watch the composite ones (i.e. VCR).

Also, the SyncBlasters can be bought with stereo audio connections.....


Novice Member
I'd recommend trying to keep all connections as direct as possible.

As for what the Plasma VGA unit does, Jon Weaver is correct that it extracts the H and V information from the composite line. But the way it does this is unique and it's designed to be the best it possibly can be. That's why it gives you true H-Sync output, and has an on-board computer to ensure no bogus syncs are passed through.

Quite simply, there is nothing as good as the RGB to Plasma VGA unit other than another RGB to Plasma VGA unit.

All the best,

Dr John Sim.


Active Member
I am trying to decide between the 2 at the moment.

I like the syncblaster because:-
Its simple.
Its seems good value.
One less power supply.
Picture quality same as the JS unit (from Jon above, but stability problem? Anyone else had this?)

JS's box seems to be brilliant but has extra power supply, more expensive and another connection in the cable run. I already have a good scart to use on it and a VGA cable. But the VGA cable is just a standard computer one. Do I need a better one to get the best out of it?

Any help would be appreciated especially from owners, JS and the guy from Keene if he is around anymore.

Jon Weaver

Distinguished Member
You might want to the the PSU issue out of the equasion.

As the SyncBlaster takes its power from pin8 (I believe), as this pin changes voltage depending on whether the signal is 4:3 or Widescreen, the SyncBlaster sometimes doesn't work.

This was solved by connecting the PSU, which is just a plug in mains adaptor which connects to a socket hanging out of the SCART plug.

With this regards, the JS box is far better as you plug 'mains' straight into the converter rather than a mains adaptor (transformer).

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