What pre-amp should I consider?
Entering into a realm of what if here but no wildlife or brain cells should be damaged by the experience...
I don't need a pre-amp...but...
...what might be a useful one for my situation?
Currently have a Cambridge Audio CD Player pushing signal into a Naksa 80 power amp which then throws the volts at pair of Krix Lyrix. Attenuation is via a good quality stepped pot built into the amp on the signal side. There are no other sources, nothing else in the system.
The result sounds really impressive and the form factor is wonderfully simple but I can't help having the feeling that something is being lost through the application of this blunt instrument.
I was using the pre-amp side of a Yamaha integrated amp some time back with a different power amp but the Yamaha is a massive beastie and I have doubts about its pre-amp qualities at the best of times.
I do have another pre-amp (Aspen GK-1 tube pre, sister to the NAKSA) but it's an old project that never quite got sorted and I've lost sufficient interest ATM to make the effort to get it back into the picture.
Can anyone suggest a small form factor quality pre-amp with up to two inputs that I might be able to 'experiment' with? Budget up to $300 but preferably less. Happy to consider capacity to accept external streaming device or have DAC capabilities too.
Comments
Seano,
I think it comes down to the output impedance Zout of the source device and the input impedance of the amp Zin. Theoretically Zout should be as low as possible and Zin should be as high as possible, ie Zin/Zout -> infinity. Of course all of that is impossible. If you search on impedance (mis) matching you will see that opinion says Zin/Zout should be at least 100.
I have just had this demonstrated in spades. I replaced my passive preamp with an ME24 which has v low Zout, 10ohms, compared to the passive transformer vol ctl which reflected the source impedance of 3Kohms into my amp 150Kohms. Chalk and cheese.
The Zin/Zout went from 50 to 15000. I am not an electronics guy but apparently this translates into the ability to drive current. I don't know but the sound has transformed.
$1200 for the ME24 preamp.
I suggest you do the calculation and if you are way over 100 then maybe you won't get improvement ?? Having said that, the ME24 is excellent. I hope and would bet the ME24 would be clearly better than your Yamaha preamp section. Trevor Zaphod Beeblebrox is prone to lending such preamps out to demo which is good, but when you like it, it is hard to say "no, my budget is $300!". Try a few, or 1 good one. That will tell you how much the Yam is hindering, if at all.
Leon has these don't know how much the power supply's will cost ?
http://www.soundlabsgroup.com.au/p/DACT-CT101/DACT+Line+Stage+Linear+Pre-amp
Cheers
Seano, you want something built in a box, no DIY?
Yeah, I'd prefer little or no DIY as I just don't have the time to devote to it at the moment. There's too much to do outside on the new land acquisition!
The Yamaha is is no danger of coming back into service - it has a role elsewhere these days.
All I'm doing now is considering whether the passive attenuator in the NAKSA is fit for purpose or whether something better can be had...
I reckon it is hard to know. Stepped attenuators being a sequence of voltage dividers
are not all the same eg using a 5 and a 10 ohm resistor is not the same as a 100 and a 200 ohm, to achieve similar attenuation. Knowing the numbers may not help. Probably the only way to know for sure is to test against a good one., but can you bypass the stepped attenuator ?
This one is pretty cheap but could be OK. Hard to know if it will do justice to your AksA.
http://www.ebay.com/itm/New-version-PGA2311-3-ways-Remote-Pre-amplifier-Preamp-/120768999130
This seems to be a review of it:
http://www.tnt-audio.com/ampli/pga2311_e.html
What's wrong with the GK-1?
It's in pieces...and requires some work to make it whole again. Plus it also needs a case. So I'll leave that till I get old.
I can easily bypass the NAKSA attenuator. Failing that I can just set it to the zero attenuation point where the resistor is actually a bare wire.
I'm comfortable that the attenuator itself is as good as it can be given that it was supplied and recommended by the designer of the NAKSA and was accompanied by the words 'more than adequate'.
I'm just curious about the metric of adequacy...
Govmint work? You could replace it with a ladder. Or shuntify it - that wouldn't take long.