There has to be an obvious reason why manufacturers make amps that have preamp overdrive but no effects loop and I'm trying to figure out why. I realize that generally speaking the simpler the circuit, the better the tone but I have never been able to put a delay (even if it's a pedal) before distortion and have favorable results. I realize fx can be added after the amp has been mic'd or even via a hotplate/slave out configuration but is there another method that I'm just totally missing the boat on?
Maybe its for people that just don't need effects. That and effects loops are a relatively new option on amps, when gain started increasing in the preamp they started showing up. Just like the depth control, multiple eqs, the multiple voicing and mid cutting.
I was actually referring to a lot of current manufacturer's designs. I imagine a loop's circuity must detract from the sound they are going for or they'd put it in.
I don't think so. I think the main reason is money. Effects loops can be simple (most are that I runs across) where you just plug in and go...some have parallell (much better) and controls for signal levels. But the main thing, an effects loop needs some way to (if it is designed for stomp boxes) change the output impedance and signal level to be compatible, and on the return needs to reamplify (in a tube amp, with a tube) the return signal back up again. Yeah..it could affect the sound, but generally they will be able to reamp the sound cleanly, not losing or gaining artifacts.
I think at least part of the reason is that many buyers in the boutique field think that a loop affects the tone, and so it suits manufacturers to go along with that - it saves them money and they can claim the amp is more 'tonally pure'. Notice that most mass-produced amps do have loops - they tend to sell to people who just want a good sound and range of features. In fact, a simple loop with a hard-bypass switch doesn't affect the tone when it's turned off. Or perhaps it does, since there is always going to be a tiny bit more wire to and from the switch, but I would expect the difference to be so small as not worth worrying about, even if you could actually hear it. If it was done just by inserting a DPDT switch into the signal path right after the MV control, I think the difference would be undetectable. The other circuitry (level and impedance matching for the loop) can all be on the unconnected side of the switch when the loop is bypassed. Of course it will affect the tone when it's on, but so does any effects unit, so again that really doesn't make (to me) any difference - it's just a compromise you have to accept to get the sound you want.
+1 on what John said. And on a 100% valve amp, a properly done FX loop adds significantly to the cost and complexity of the amp. So some do it via op-amps, which leads to criticism from purists.
I think you are right. The last time I brought this up I was told something to the effect " real guitar amps do not have effects loops". Jim
Thanks for the responses. So if someone wants to use the gain of one of these amps with some type of delay, they're screwed then?
I think John Phillips is right on it. I think that many small builders don't want to screw around with it because it's just extra work (not just in the design, but in the building of every amp) and a little extra cost and they feel that many of their customers don't care about it. And often, they say that the tone w/o the loop is purer. Perhaps, but I agree that if done properly--which is apparently not that hard at all--you'll not notice any difference. FWIW, Fred (@ ÷13) is going to be building a new amp that does in fact have a MV and an effects loop. I've heard a couple of his session/road-warrior customers play through it now...it is a freakin monster of an amp and he's got that loop and MV dialed in. I've heard it with and w/o both features and there is absolutely NO DIFFERENCE to my ears. None.
No. There's always the wet rig option, though it's a bit more troublesome, it does actually sound better than a loop, IMO.
Sure - or do the Landau thing and place the processor after the mic. Just seems like a pain in the ass...
That is a wet rig that Landau's using. It doesn't have to be as big a PITA as his...but he does it that way because he wants what he considers the best sound, I'm sure. Your wet rig can be as simple as: - direct box with line-level out - effects processor - mono power amp - 1x12 wet cab And it can sound FANTASTIC.
You can also simplify further by just using the effects return of a small combo amp for the wet-dry thing. I use a Tech 21 TM60 which is lightweight and transparent. This method sounds a zillion times better than an FX loop to my ear.
If there is no slave/direct out on the amp in question and only speaker outputs, is something like a Hot Plate the only alternative?
Well if by "something like the Hotplate" you mean an attenuator per se, the answer is no. There are plenty of devices that sit between the amp and the speakers that'll give you a line level out. H&K and Palmer, among others, make some devices commonly used this way. But if the amp has no other output besides the speaker out, then yeah, you either have to add one, mic the amp or get a box in there between the amp and the speakers. Anyone else got any ideas? (that was a good one, I thought Riscchip, BTW!)
The W/D thing though cool, would be overkill for my application. Maybe if I was a touring pro it would be a different story. I'd prefer having my intended sound coming from one source if nothing else to simplify mic'ing. Different strokes I guess. I have heard w/d/w configurations and they do sound killer (when standing dead center, of course).
If you are running an amp with two input channels ( like most D13's for ex.), you can split the signal and run dry into the gain channel and wet into the other channel. You could add an OD pedal on the wet side before the delay if you like. Also, some delays have a dry and mix/delay out. You can run each of those signals into separate channels. Of course you can always run an overdrive before your delay. I've also found a nice analog delay sounds pretty good in front of the amp- better than I would have expected.