Connecting your source directly to a power amplifier

[wuwhere]

Quote:

Thanks Donald - at close to 4K for a secondhand unit (seller claims it was 9k new), I can see that the Silver Note was a 'cost no object' undertaking. Short of a Lotto win, that will have to remain with the Levinson and Meridian kit in the unattainable-but-desirable category. 
 
OT, but Levinson's ML-2 reportedly puts 400W into .5ohms, has 'unlimited' current delivery (?) yet each mono amp is rated at a mere 25W into 8 ohms. Extrapolate that to a headphone amp and Levinson could have built an immensely powerful '1 Watt' headphone amp but it would have cost ~30k new. I'd imagine that it would have paired very well with your Silver Note.  

 
Classe built a similar amp, the DR3 VHC (very high current), that doubles in power every time the speaker's impedance is half, for Apogee Scintilla's speakers that drop below 1 ohm at certain frequencies.
 
Audio magazine reviewed the ML-2, it was able to arc weld two steel plates. That's how stable it was.

 

[estreeter]

Having been forced to shift an old arc welding unit from one side of a workshop to the other back in my Army days, that's a scary thought, It had wheels, but they were wonky from years of abuse, meaning we had to manhandle the beast. I would hope that technology has improved  the welders lot in the years since. 
 
Still, a lot of the early power amps werent exactly lightweight, were they ?  

 

[wuwhere]

It became ridiculous. Mono amps with the power supply a separate box, they just got too heavy for one person to lift. So for a stereo pair, you have 4 boxes. I had a mono pair of Krell KMA 160 for my Scintilla, each weigh 85 pounds.

 

[estreeter]

wuwhere, I went right through Arthur Salvatore's Entry Level recommendations, but his speaker recommendations look awfully dated. I take his point re buying secondhand, but 30 year old speakers arent my idea of a good time, Please post any other links you think may be of value to a newbie speaker rig wannabe like myself.   

 

[obobskivich]

Unlimited current = unpossible. Sounds like an adwriter got carried away.

 

[estreeter]

I think its along the lines of 'off the charts' - in any case, how much kit is that linear from 8ohms down to .5ohms ? 

 

[minimus]

Arthur Salvatore was the biggest proponent of the idea that preamps are unnecessary and, even worse, detrimental.  But even he seems to have backtracked on that view, has offered a technical explanation of why an active preamp might be beneficial, and now is an advocate of the Coincident Linestage, an active tube preamp, a supposed steal at $5K.  (Of course, he loves everything made by Coincident for some reason -- nobody else seems to like Coincident quite as much as he does, and regular complaints show up on Audioasylum regarding the business practices of Israel Blume, the owner of Coincident.)
 
I own a PS Audio Perfect Wave DAC, which has a digital volume control.  PS Audio recommends going "amp direct" if the DAC is your only source.  I have tried this on many occasions and have never been satisfied with the resulting sound quality.  For some reason, the sound quality becomes somewhat shrill and fatiguing and the soundstage just collapses in on the speakers.  I thought the problem was the digital volume control of the DAC, where you "lose bits" unless the volume is turned way up, a practical impossibility with most efficient speakers. 
 
I tried a passive volume control, the Lightspeed Attenuator, which gets glowing reviews on Audiogon as a giant killer.  With the Lightspeed Attenuator, I was able to turn up the volume on the DAC to its maximum level, bypassing its digital volume control, and adjust the volume using the Lightspeed Attenuator.  The resulting sound quality was very similar to going amp direct -- a lean, fatiguing sound, with a collapsed soundstage. 
 
So, despite the theory that the best preamp is no preamp, my practical experience is that an active preamp always sounds better than no preamp or a passive volume control in my system.  Dynamics are better.  Bass response is better. Soundstage is wider and deeper.  No matter what amp I have used -- a McIntosh MC275, a VAC Phi 200, a Pass Labs 150.5 -- the result is always the same.  Arthur Salvatore might have once argued there is something wrong with my source, my amp, or my speakers, although I believe he is less dogmatic about that these days.  In any case, I don't really care what Arthur Salvatore says.  A lot of people have come to the same conclusion -- that regardless of the "theory", they really prefer the sound quality of an active preamp.

 

[estreeter]

Thanks for the feedback. Minimus. I dont accept everything that Arthur has to say at face value, but (on paper, at least) he reminds me of a notorious retailer in Brisbane who is just as likely to greet you with a scowl as a smile and really doesnt seem terribly interesting in 'new' customers. God help anyone who rings him to ask for prices on kit - that really get him fired up. The thing is that he is one of very few dedicated 2-channel resellers in Australia these days, and the people who have learnt to deal with his eccentricities swear by his experience and product knowledge. Mr Salvatore's extensive anti-Stereophile rants point to a similar level of eccentricity, but audio would be poorer without these folk. They are a welcome tonic to the likes of Antony Michaelson endlessly banging on about MFs latest wonder-toys. I know bugger-all about high-end audio, but I know a used car/real estate salesman when I hear one. 
 
Getting back to the passive attenuator/preamp thang, as I said before my initial attraction was sparked by the prospect of getting 'something for nothing'. Short of the slim possibility of damage to one's equipment etc, I cant see what the harm is in trying it for a week or so - even if it doesnt gel with source A and amp B, you havent spent any money to discover that. Your experience seems to mirror that of many others who have gone down the passive route and found themselves reaching for their active preamp, but its all good - until we start shelling out for the aforementioned 5K 'bargains', that is.  

 

[obobskivich]

I think its along the lines of 'off the charts' - in any case, how much kit is that linear from 8ohms down to .5ohms ? 

Real question: how much does it matter?

As far as a trial - give it a shot; won't hurt anything and you'll get it out of your system.

 

[estreeter]

It matters if it means you end up spending less to get a similar result ....  I dont know about you, but I also get annoyed with 15 power cables dangling down the back of a desk - had that in 2008 and it really drove me batty. Less is more, Obo my friend 

 
(might I add that using a USB-powered DAC/amp from a laptop has a perverse pleasure to it : barely mid-fi, granted, but a world away from the dreaded tethers that bind us to that all-important socket).

 

[estreeter]

minimus, I suspect that you have seen this:
 
http://psaudio.com/vanilla/discussion/487/pw-dac-and-volume-control/p1
 
The 'silver bullet' stepped attenuator solution seems a bit ironic for mine - PS Audio put all that effort into a digital volume control and these guys had to go and find a workaround. Still, telling folk that they can just hook their DAC up to a power amp without more specific advice probably wasnt their brightest move. 

 

[wuwhere]

Quote:

wuwhere, I went right through Arthur Salvatore's Entry Level recommendations, but his speaker recommendations look awfully dated. I take his point re buying secondhand, but 30 year old speakers arent my idea of a good time, Please post any other links you think may be of value to a newbie speaker rig wannabe like myself.   

 
Yea a lot of that info is old. And I don't necessarily agree with all of his stuff as well. I've been out of the speaker domain for awhile. The Wilson Watt/Puppies impressed me with their small footprint but expensive.

 

[estreeter]

Wilson ? That;s like telling a drowning man to hold on a little longer till fishing season ......  

 
28K a pair. All due respect, but my car didnt cost 28K ! Still, there IS one vague chance that I might own a pair:
 
http://www.ozlotteries.com/play/oz-lotto
 
At 70 million AUD, I could have Wilson Sasha speaker cabinets for ashtrays - I don't smoke, but it would inflame a great many Wilson fans. I hope I can get cabinets that match the decor on my yacht. 

 

[wuwhere]

Quote:

Wilson ? That;s like telling a drowning man to hold on a little longer till fishing season ......  

 
28K a pair. All due respect, but my car didnt cost 28K ! Still, there IS one vague chance that I might own a pair:
 
http://www.ozlotteries.com/play/oz-lotto
 
At 70 million AUD, I could have Wilson Sasha speaker cabinets for ashtrays - I don't smoke, but it would inflame a great many Wilson fans. I hope I can get cabinets that match the decor on my yacht. 

 

 

[obobskivich]

Wilson ? That;s like telling a drowning man to hold on a little longer till fishing season ......  :eek:

28K a pair. All due respect, but my car didnt cost 28K ! Still, there IS one vague chance that I might own a pair:

http://www.ozlotteries.com/play/oz-lotto

At 70 million AUD, I could have Wilson Sasha speaker cabinets for ashtrays - I don't smoke, but it would inflame a great many Wilson fans. I hope I can get cabinets that match the decor on my yacht. 

h34r: