2. amps-preamps
  3. 123296-8622

Will Changing my 100 Watt Tube Amp to a 200 Watt SS Amp Solve My Problem?

Hello All,  I have a 100 watt Audio Research VT100 mk II amp, with an Audio Research LS-25 preamp.  My speakers are relatively low in sensitivity, and I find that I must turn the volume up to 3 o'clock on the preamp to get enough volume for a loud listening experience.  When I do that, I am introducing more background noise.

I would like to achieve a quieter noise floor.  I am also curious about the limits of the 100 wpc amp with the Mira Monitors.  Would an older Krell 200 watt class A amp "control" the speakers better?  If so, what are the benefits of this?  There are a few amps on this site that caught my eye, all about the same value as my amp, so I can potentially make a move with very little cost.  Is this a good idea? How much wattage increase is necessary to get a significant enough difference?  Would a jump to 150 watt solid state be sufficient?


here are the 3 amps that caught my eye:

Ayre: https://www.audiogon.com/listings/solid-state-ayre-acoustics-v-5xe-amplifier-2016-02-05-amplifiers-h...

Krell: https://www.audiogon.com/listings/solid-state-krell-ksa-250-2016-02-14-amplifiers-91754-monterey-par...

BAT:
https://www.audiogon.com/listings/solid-state-balanced-audio-technology-bat-vk-250se-bat-pak-2channe...



You can see my complete system here if you want to know more about the other components:  https://systems.audiogon.com/systems/5421



Thanks!
Mark
marktomaras
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mattmiller
1,180 posts
 
I just mounted a new Dynavector 20X2 on my Xtension 10 and I have noise too! :-( I really dont think its the cartridge...or my Chinook phono pre...or my Manley Jumbo shrimp linestage, nor is it my amplifier. I think noise is getting in from the house electrical system. All I know is that it sux major *(&^. otherwise my system would be awesome sounding. Now im looking at power conditioners (yuk).

Matt M
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almarg
8,673 posts
 
AL, What speaker manufacturer does not say this..?? ROFL.
(please dont answer that)

All I was saying is that Mark should try a SS amp (of course one that will drive the speakers) .
And all I was saying is that:
... before going to a more powerful amplifier it would be prudent to research how much power the particular speakers can handle without their sonics degrading, or worse. The only relevant spec I can readily find for the Rockport Mira Monitors is a minimum amplifier power recommendation of 50 watts.
My comment being inspired in part by someone else's mention of 400 watt monoblocks, in the post just above the post you made yesterday.

Glad my comment provided you with some amusement.

Regards,
-- Al
sdcampbell
2,136 posts
 
I'm coming late to this discussion, so I'll try to be succinct. One of your problems has already been identified: the preamp, for whatever reason, has a poor signal-to-noise ratio. This could be due to mediocre original design, but it could also be due to deterioration of some of the internal electronic components. It would make sense to get a good technician to diagnose the preamp and make any indicated repairs.

The other relevant point is that increasing the amplifier power from 100 watts to 200 watts will not have much effect. Doubling the output power of the power amp will only increase the maximum audio signal level by 3db, which is discernable only as a slight volume increase. Your AR VR100 amp is a fine unit, but it needs to be paired with more sensitive speakers if you want to listen at high decibel levels. As a rough rule of thumb, I like to pair low to moderate power tube amps with speakers rated for 90-92db sensitivity or higher.

Just my 2 cents, FWIW.
marktomaras OP
535 posts
 
Thank you all.  There are a lot of good info and ideas here.  I am interested in what sdcampbell said about the poor signal to noise ratio.  Perhaps that is worth investigating.  Newbee, I have tried what you suggested, but I think I need to refresh my memory by doing it again.  Saturday Morning is listening time for me, so I'll tackle that in the morning.  By the way, I just listened to some Ella Fitzgerald on vinyl at low volume and it is excellent.  No hiss, no problem.  But that was at a volume level one could have a conversation over...
rwwear
2,692 posts
 
If you do decide on the Krell amp, I have a much nicer specimen and it has also been upgraded to a 250S.
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