audio research ls25 mk1 volume issue


Hi guys,
i am a proud owner of an arc ls25mk1.. amazing machine. my question is asimple one for all you guys who know the answer. i do not. I seem to have to turn the volume up past 12 oclock to get a decent volume. even higher for a little louder. i have checked the bias and its perfect. i have a pair of vtl mb 125 mono at 125 per channel and i have ascendo c7 speakers, they have a db rating of 88.. is this normal?
any help will be greatfully appreciated
syhilly
The Main Output is selectable for each input: 18db, 12dB, 6dB for the Balanced outputs and 12dB, 6dB, 0dB for SE output.

Have you checked to see what the gain settings for EACH input are? That should solve your problem.
ok i understand . thats the knob on the front that has low , med and high. i always use high.
thanks
88db for the speakers isn't really that bad, especially if your amps put out 125 watts. What source are you using? Maybe the output of the source is lower than normal.

The 12 o'clock, (or even more) setting is normal for most phono playback rigs, but it seems kind of low for CD playback.
i listen to both cd and vinyl. seems to be the same situation on either input.. i change the ooutput to high. sounds amazing, but was wondering if there is anything else i can do
i have a raysonic cd 128 tube cd player and i use a music hall t.t. with a n arc ph3se
Another thought. Try to cycle through the low, medium, high knob several times. Make sure the volume is all the way down. That's a relay driven device and maybe it's stuck.
i iwll try that as well.. thanks so much for your input. you have been very helpful
thanks again
The specs on your CD player show an output of 0-2.2v. I am assuming that it has a varible volume control on the output. Have you tried turning it up from the CD remote?

The setting for your phono system seems right to me.
no, i have not tried. i did not know that it has that. will check my remote.thanks so much
Forgive my asking, but what's the problem with having the volume knob at 12 o'clock? In my opinion, this is ideal as it provides you with some room for volume adjustment, rather than being extremely loud with minimal turning of the knob.

In your case, you should be able to run the preamp fairly wide open because it doesn't sound like you're overloading your amp/speakers.

Michael
Syhilly, my understanding is that, especially for tube preamps, that they frequently sound better when the volume control is wide open. (That's what the owner's manual for my old VAC preamp said, anyway.)

Michael
I think you are kind of lucky. I get tired of preamps that are too loud with the vol nob on 1/8 the way up. Maybe you are right in the sweet spot?

88 is a fairly low output speaker too.
The position of the volume control is arbitrary and has nothing to do with "being hard on your tubes." The actual listening level will be determined by a combination of factors, namely: the output of your source component combined with the amount of gain provided by the preamp and gain of the amplifier and the efficiency of the speakers.

Earlier posters are correct that for practical reasons it is preferable to run your LS25 near 12 o'clock where there are many more subtle steps of adjustment available on the control than at 9 o'clock where there are relatively few. If you count the steps available between each of the indicator lights on the volume control you will find that there are only 2 or 3 steps between the lights down at 8-9 o'clock and there are as many as 6 steps between the lights at 10-2 o'clock. It is easiest to do this with the remote by quickly tapping the VOL + button.

ARC uses a high quality resistor network for volume control rather than a traditional potentiometer and they do this for better and more consistent sound quality across the entire range of the control. On older preamps with a potentiometer, you would actually get better sound quality as you turned the knob up higher because there would be less of the "pot" present. Getting rid of the pot entirely and running the preamp wide open would be better still. The LS25 (along with other modern preamps that use a similar scheme for volume) sound much more transparent like a preamp run "wide open" at all times.

The LS25 gives you the ability to optimize the volume range for each individual source by using the low, medium or high GAIN setting knob (6,12 or 18 db). Go through your sources and set the GAIN knob so that each source can be run with comfortable listening levels occurring between 10 and 2 o'clock on the volume control.

This feature can also be useful to make switching between high output digital sources and low output sources. like phono, more seamless.
With the highest gain setting selected, I'm always between 12:00 and 3:00 (LOUD!). LS25-> VT130SE -> Ohm 100+sub or Maggie SMG+sub or Verity Parsifal Encore. Just a somewhat back-ended attenuation scheme on this pre.

Marty