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High Output Preamp for First Watt SIT-3?

I'm new to the audiophile world and recently purchased a First Watt SIT-3 with Magnepan .7s.  I have a Mytek Brooklyn Bridge for streaming, though I prefer to play vinyl with my Mofi Ultradeck.  The Mytek serves as the phono stage (69dB gain for MM?), and I don't use a preamp;  the Brooklyn is connected directly to the First Watt. 

I understand that the SIT-3 is only 11.5 dB of gain, and that's extremely low compared to most amps.  I like most everything about the system except for the fact that I have the Mytek maxed out volume-wise many days.  Certain LPs are cut quieter, and I wish I had more power.  There are times streaming where the Maggies aren't getting to their sweet spot.  I realize the Maggies are a lower sensitivity speaker. 

What should I look for in a preamp to fully drive the SIT-3?  Eventually, I'd like to replace the phono stage instead of relying on the Brooklyn.  Is there a tube preamp featuring a phono stage with sufficient output to drive my amp in the $4k range?  Otherwise, I'm eyeing the Modwright PH 9.0 and a linestage preamp, realizing that this will probably be costlier.  I'm looking for a warm sound, not analytical but engaging. 

Any help is greatly appreciated.  I'm a working musician with a basic understanding of related electronics but little experience in this world. 

murphbass

Showing 3 responses by atmasphere

atmasphere's avatar
atmasphere
11,567 posts
 
Do you believe the S.I.T.3 would improve SQ further if driving a 12 or 16 ohm speaker load (due to lower distortion) or is 8 ohms optimal for this particular amplifier?
If the amplifier begins making a greater percentage of higher ordered harmonic distortion into higher impedances, even though its THD might be lower, increasing higher ordered harmonics is never a good thing!


atmasphere's avatar
atmasphere
11,567 posts
 
@murphbass  **All** amps make lower distortion into higher impedances. You can see this in their specs. You might think the difference to be 'negligible' but the distortion components involved are higher ordered harmonics. Since the ear uses these to calculate sound pressure, it is more sensitive to them than almost anything else, since the ear has about 120-130dB range! So that small increase is **huge** to the human ear.

The ear converts all forms of distortion into tonality. Higher orders are heard as brightness and harshness and are why solid state amps sound bright. But put them on a higher impedance and they sound smoother and more detailed both at the same time.


Tubes work better in this way into higher impedances too, as does class D. If **sound quality** is your goal, your amplifier investment dollar will be better served by a speaker of higher impedance that otherwise performs the same.
atmasphere's avatar
atmasphere
11,567 posts
 
I think I'll listen to the sentiment of most of the contributors to this thread and build around the better of the two variables: my amp. I like the idea of having a high efficiency speaker on hand when I add an SET amp. Since it's hard to demo most of what's out there, I really appreciate everyone's recommendations.
Back in the 1970s Radio Shack made a number of low power transistor amps, varying between 1 and 6 watts output depending on the model. You'd be surprised how much power than can actually be; Radio Shack did well with these amps and made sure they had plenty of fairly efficient speakers on hand to take advantage of that power. These little amps have an ardent following to this day; I own one myself and can vouch that they sound surprisingly good (when properly refurbished), and just like the Pass they have a predominate 2nd harmonic as part of their distortion signature.


So you need more efficient speakers. One of the reasons this amp doesn't have a lot of gain is its meant for speakers of greater efficiency where the gain simply isn't needed. There's been a lot of good advice here- get that amp on a speaker that has good efficiency and the results will be excellent. There isn't a reason why resolution has to take a back seat to efficiency either- so I wouldn't worry about that. To keep distortion down though and yet still make reasonable power, I'd be looking at an 8 ohm speaker rather than 4 ohms.
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