Mainline setting for use as pre

[JamieMcC]

Hi guys when using the Mainline for preamp duty in front of a solid state power amp (I picked up a Technics SE-A900SM2 to play with for peanuts off of fleabay ) is there a preferable Mainline output configuration? At the moment I am just using a standard trs to rca cable and am thinking about making up a XLR to rca to try. There are some noticeable effects in switching between balanced & single ended and high & low outputs. Any advice or words of caution appreciated.

Cheers
Jamie

[Doc B.]

Any setting will work, so you should use the configuration that sounds best to you. You may get a little better S/N with the lower impedance output setting, but the Mainline is very quiet and I don't know if you could discern a difference.

[Paul Birkeland]

There are some noticeable effects in switching between balanced & single ended and high & low outputs.

You will want to stay on the unbalanced output setting since you are using the TRS jack.  You can use whichever impedance tap that you find sounds best, as both are more than able to drive your power amp. 

[JamieMcC]

Thanks for the advice, much apreciated. I also put some fresh batteries in my Quickie today to try and while there is a some low background noise present at the speakers when nothing is playing (with the Mainline it is dead silent) as soon as the tunes start its not noticable and the Quickie has a engaing charm all of its own.

Cheers
Jamie
 

[johnsonad]

Jamie,  did you ever try your Mainline as a preamp and if so, how did you like it?

[JamieMcC]

Hi Aaron

Yes it worked well enough when I tried with the Technics SE-A900SM2

[ALL212]

hmmmm...I feel left out   

Can the same be done with the Crack?

[Paul Birkeland]

Yes.

[ALL212]

I've created a cable for this.  RCA ends are a bit too short but they work.

I wasn't paying attention to what I had turned on and got some strange noises on power up.  Turn on everything except the power amp and let it all warm up for 5 minutes first.  Then turn on the power amp.  I'm using the Crack with an Odyssey Audio Khartago for power and it really sounds good!


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[JamieMcC]

Fwiw I have the Mainline on pre duty again with the Technics SE-A900SM2 it’s the first time I've used the combination running 100db open baffle speakers.  I did have the Sex driving the mids and tweeters and the bass drivers amped separately which sounded very good. Recently I tried running the bass drivers off the Sex as well and wasn't really surprised it struggled with the extra load and would start to clip easily.

So now trying out the Mainline/Tech SE-A900SM2 combo the Mainlines weight in the mids is coming through nicely and the bass has more punch and control.  The Teac seems really transparent and the only drawback I find with the combo is a bit more edge than I would like to the top end with one or two tracks with the Teac in the chain compared to the Sex.

Hum wise I can only hear the very faintest of hum from the 100dB drivers and that’s only when my ear is an inch or two away from the speaker’s cone!

The OB speakers have been a bit of a revelation with resolution and presentation really impressing.

[AllanMarcus]

So how does one use the Mainline or Crack as a pre? Turn the volume way down on the bottle head?

[JamieMcC]

So how does one use the Mainline or Crack as a pre? Turn the volume way down on the bottle head?

Yes start at zero with my 100db speakers the lowest volume on the Mainline still gives a low level easy listening level if I need to mute I just select a different source or adjust the output level on my digital source.

[Paul Birkeland]

So how does one use the Mainline or Crack as a pre? Turn the volume way down on the bottle head?

All you need to do is plug in a 1/4" TRS to RCA adapter.

Trying any unfamiliar preamp requires starting at the lowest volume for the safety of your speakers.