[C38368]

What exactly is the difference?
Some amps (like the GS-1) have both, whereas other (MAD Ear++ comes to mind) have only preamp outs.

From what I've been able to put together, loop/tape outs send out the exact same signal that the amp receives.
So I figure that preamp outs must do something to the signal, but I haven't got any clue what that something might be.

Of course, the reason I'm asking this is to figure out just what I'd do with an amp that had preamp--but not loop--outs.

 

[fatp3nguin]

I think the main difference between a loop-out and a preamp out is that a preamp out is amplified and volume controlled. I believe a loop-out is just a line level output.

 

[C38368]

Fair enough. What would one plug into preamp outs, then?

 

[EdipisReks]

source->preamp->poweramp->speakers

 

[Jeff Wong]

A tape out is a more direct path (pure line level) and doesn't get routed through the volume pot.

 

[Jahn]

yep, a tape loop is like a line level loop as mentioned above. like the one on my STAX SRM-1/MKII, it's a line level loop out. That means that the analog signal coming in defines the level of the signal looping out to the pre-amp or power amp. This happens regardless of how loud the volume knob is set for the headphone out.

My Melos' Active Tube Pre-amp loop out, on the other hand, passes that line level signal in through a gain stage before looping back out to a power amp - therefore, my volume knob controls the volume of the signal looping out, just like it does to the headphone out. This is why I want my Tube Pre-amp loop out to go to my STAX, it's my high quality signal out. My Melos' passive loop out will go to my vintage receiver acting as the speakers' power amp, and the Melos' tape loop out, which isn't affected by the gain stage at all, will go to my computer's analog in for plain jane recording of my crappy vinyl.

 

[C38368]

Quote:

Originally Posted by EdipisReks source->preamp->poweramp->speakers

So in other words, no good for headphones?

 

[Jahn]

Quote:

Originally Posted by C38368 So in other words, no good for headphones?

a tape out won't be getting any of the benefit of an amp - it's basically a pass-through, with no volume control, and has RCA outs most likely anyhow, which you don't plug directly into a headphone.

a headphone amp is basically a preamp, which is why the melos' headphone out is controlled by the volume knob, just as the tube gain stage active pre-outs are. in fact, i used Pinkie, my old headphone amp, as a preamp too - i just used the headphone out and a 1/4 to RCA adapter, and plugged it right into my receiver's preamp in.

so, for headphones, preamp good, tape out bad.

 

[C38368]

Quote:

Originally Posted by Jahn a tape out won't be getting any of the benefit of an amp - it's basically a pass-through, with no volume control, and has RCA outs most likely anyhow, which you don't plug directly into a headphone. a headphone amp is basically a preamp, which is why the melos' headphone out is controlled by the volume knob, just as the tube gain stage active pre-outs are. in fact, i used Pinkie, my old headphone amp, as a preamp too - i just used the headphone out and a 1/4 to RCA adapter, and plugged it right into my receiver's preamp in. so, for headphones, preamp good, tape out bad.

Err... I wasn't totally clear on that. What I meant was that the preamp outs aren't all that great for daisy chaining headphone amps, as opposed to loop/tape outs.

Describing the proper headphone outs as being functionally similar to RCA preamp outs... makes much more sense than my previous understanding.

Thanks

 

[EdipisReks]

Quote:

Originally Posted by C38368 Err... I wasn't totally clear on that. What I meant was that the preamp outs aren't all that great for daisy chaining headphone amps, as opposed to loop/tape outs.

yep, preamp outs definitely aren't comparable to loop outs.

 

[rickcr42]

never a good idea to daisy chain gain stages unless you absolutely need the extra gain which is what you would be doing if you use a headphone amp on preamp outputs.
The tape record outputs are usually from a tap directly off the input selector and before ANY additional switching or gain.If anything there will be a gain reduction on this output (line level pad).Because a headphone "amp" also includes a gain stage this level is amplified only as much as is needed to drive headphones.

The preamp outputs are the end of the line from input of source to line level output so anything in between will also be at this output and that includes any gain.Put a headphone amplifier on this output and you usually will not only have too much gain but too much noise in the signal as well from the additional amplification of both the already boosted signal level and any noise added by this boosting.This gain+gain+driver may work fine for a loudspeaker which you listen to at a distance but low noise is critical when the interface is not speaker+air+ears but headphone+ear directly.
You also will lose much of your volume control range unless you add an inline pad at the input to the headphone amp as sot of an "anti-amp" to toss off the excess.

Hope this helps

Rickmeister