Soundcraft Analog 24.8 Insert Points/Bal, Unbal??

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DeeCeeMonterey

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Hey all.. there's something I maybe don't understand completely, and I thought maybe someone could help.

The insert points on my analog Soundcraft Spirit Studio 24.8 are balanced, . (I think)
COPY AND PASTE FROM THE MANUAL:

All channel inputs are balanced, i.e. there are separate
+ve(hot) and -ve (cold) wires for each signal plus a
ground.

(here's the part I don't understand)...

The Insert is a 3-pole 1¤4" ‘A’ gauge Jack Socket

The mix, group and auxiliary outputs are ground compensated
and provide a very effective way of
optimising noise immunity, without the cost and complexity
of balanced outputs.
END OF COPY FROM MANUAL

The ins and outs on my ART Dual Levelar compressors are balanced (xlr or 1/4", I am using the 1/4")
and the ART manual says that inputting an unbal cable is ok, ..But aren't "TRS to TS" 1/4" insert cables BALANCED, just by the way they are built? or does "BALANCED" not apply when it comes to insert cables?

I am using the insert cables to employ compressors at various channel
insert points.

After returning from compressor to mixer, I feel like the signal weakens. I AM bringing up the output on the compressors, but I feel like I am experiencing that "balanced to unbalanced" gain reduction thing, that can happen, going from bal to unbal, or unbal to bal(?).

(Since the CHANNEL INPUTS are BALANCED, doesn't it stand to reason that the INSERTS are, as well?)

Or, again, does "balanced" not really apply when referring to an insert cable(?) I'm confused, any help? Thanks, Soundcraft hasn't been very helpful and the manual is vague. Whatever thoughts any one with this knowledge would have would be interesting, I'm sure. Thanks again, Dan:confused::confused:
 
A single TRS insert is unbalanced, send and return on one connector. In the case of the Soundcraft Studio it's tip-send, ring-return. Page 7 of the manual illustrates it clearly.
 
Actually, as Bouldersoundguy points out, the Soundcraft manual is very clear.

Just to expand a bit on the "why" of all this, a balanced feed uses all 3 connections on a TRS (or XLR) connector: one positive going, one negative going plus the ground/earth.

Since an insert is a two-way circuit, a TRS jack simply doesn't have enough connections to be balanced. There ARE a few mixers with balanced inserts...but they do it by using 2 TRS sockets (one send, one return) rather than putting everything on a single connector.
 
Hi, and thanks, boulder.. Thanks for clearing up my confusion on the insert point itself. So, i DO have one ART compressor, the PRO VLA, which has a switch on rear, for bal/unbal. Should I set this for unbal?(-10?) It is currently at +4. I tend to think I should keep it at +4, because the INPUTS on the board are bal(+4) and the outputs from the multitrack are bal.
The other four (ART dual levelar) compressors, do not have the switch, is there a way to remedy this?
ps, i lived in Boulder for 5 yrs... getting cool yet? thanks again.
 
Hi, and thanks, boulder.. Thanks for clearing up my confusion on the insert point itself. So, i DO have one ART compressor, the PRO VLA, which has a switch on rear, for bal/unbal. Should I set this for unbal?(-10?) It is currently at +4. I tend to think I should keep it at +4, because the INPUTS on the board are bal(+4) and the outputs from the multitrack are bal.
The other four (ART dual levelar) compressors, do not have the switch, is there a way to remedy this?

The +4 and -10 settings are for operating level. Balancing a signal is a different thing from operating level. Normally for pro gear you want it set to +4, but some inserts are -10. If setting your compressor to +4 means you have to turn the threshold way down to get it to compress then switch it to -10.

Most likely you'll have no trouble with unbalanced connection, but if you do take a look at Sound System Interconnection.

ps, i lived in Boulder for 5 yrs... getting cool yet? thanks again.

We've had one light snow and it's gotten back up to the 60s. Like usual around here you have to take layers wherever you go. It can be 67° at 1pm and 30° at 7pm.
 
Arrgh!! Well, that 'reaction' is a bit made-up, now, but I realized something about four days ago, and that was how I felt at the time.
The Tape Trims on my Soundcraft 24.8 has detents (those notches in rotation) at 12 oclock, on every channel... I DID trim these knobs a bit, but did not notice the detents. I didn't think to check the specifics on the knobs themselves, but while thoroughly reading the manual (again) I found this info: 12 oclock is the detent intended for +4 level tape returns, and 3 oclock (altho there's no actual notch @ 3oclock) is intended for -10 level tape returns.
And get this!... the 1/4" tape SENDS are -10, (I can make this work great actually, 'cuz I can use my 24bit a/d-d/a converter- unbal in's, then go out via lightpipe to the mltitrack record deck) ..But unless service personnel goes INTO the Soundcraft motherboard and clips off two resistors, the tape sends are -10. This mod. will render the tape sends +4. (that's actually pretty cool) Thanks, Soundcraft, nice and easy! (not) No worries, I've got the levels to normal, and in fact, I'm running just shy of 12 oclock and getting plenty of signal! THANK YOU ALL FOR THE TROUBLE SHOOTING HELP! (ps..I originally had the tape trims @ 7oclock, or "zero" trim gain, which began my concern about weak signals)
 
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