- #4
- Publié par
abelus le 17 Fév 2016, 14:47
Loop History
In the '70s when people first started using effects loops, the loop was just a pair of jacks with an interrupt contact on the 'return' jack.In most cases, these jacks were inserted into high-impedance circuit points that could not drive the effect inputs very well, so there would be level and tone changes when effects were plugged in. Techs and amp designers got a little fancier in the '80s, adding 'Send' and 'Return' controls. At least you could chop the signal down enough not to overload your pedals anymore, but you still had significant loss. So, some loops had gain added after the loop to make up for the expected loss. This gain was always in there, adding noise, boosting whatever noise was coming from the preamp, and mostly being more trouble than it fixed. What a compromise! And some big-name companies are still doing this....duuumb. (PV 5150-series, Fender Twin, the Dumblater).
In the '90s, studio techniques were applied to the whole "effects loop fad", and suddenly loops seemed to have something good to offer. 'Parallel' or 'mixing' loops became popular - with a lot of help from The Ultimate Tone - and these allowed the 'dry', or uneffected signal to stay inside the amp. The loop now became what sound engineers call a "side chain". The signal is tapped off, routed through the external effects, then mixed back in with the dry sound. The effected sound is called the 'wet' sound, as you might have guessed.
So what does a mixing loop do that a simple loop can't?
One of the most important benefits to parallel loops is that you never have an instant without sound. Many of the effects processors introduced through the '80s and '90s would mute the signal for a fraction of a second while patch changes occurred. This meant a drop-out in your sound: a tiny slice of time filled with SILENCE that seemed to last forever! With a mixing loop, your dry sound is always there even if your processor takes a little nap.
There are times when you want really "in your face" effects sounds that need a simple series loop like those primitive amps had.
