help me to understand the gain

You can essentially nullify the gain of the preamp (reducing it to 2db) by placing a pair of 10db Rothwell Attenuators, or similar devices that are available from other manufacturers, at the preamp inputs.

However, to obtain an adequate overall reduction in gain, you would have to place an ADDITIONAL 10 or even 20db of attenuation at the power amp inputs, and there would be a problem doing that.

According to Stereophile's measurements of your preamp, its already very high output impedance of 2.7K at mid and treble frequencies rises to 11.5K at 20Hz. That rise will result in a significant deep bass rolloff when driving most or all readily available passive attenuators. (I've measured the input impedance of my Rothwell's as being about 33K, which is much too low to be driven properly by a preamp having that kind of output impedance).

As I see it, the fundamental problem is that your power amp is much more powerful than what is required by 101db speakers under typical conditions, and although (as was said above) power and gain are two different things, they generally have a significant degree of correlation. I would suggest selling the amp and replacing it with something that is less powerful and has lower gain. Having to pay for fewer amplifier watts may also allow you obtain better sound quality per amplifier dollar.

If you do that, be sure to choose an amp having high input impedance (ideally 100K or more), to be a proper match for the PrimaLuna.

Regards,
-- Al

i would replace preamp for McCormack with unity gain. one of my super-favorite is MLD as active in unity gain. perfect correlation indeed.

Your DNA1 has an input sensitivity of 1.2 volts .. which means a 1.2 volt signal will drive the amp to it's rated output (150 WTs)

The PL3's output voltage is 5 volts as measured in a Stereophile review and way to much output for the DNA1's input stage

The PL3 is over powering the DNA1 input stage and you can't use all the volume control available in the PL3 as it only takes 1.2 volts to drive the amp to max output

You can put a 10db attenuator at the amp's input or just remove the PL3 and drive the DNA1 from the Dac ... which has Tube output and a volume control

The Dac's 2 volt output is much more compatible with the DNA1's 1.2 volt input sensitivity

Unless you need the PL3 to switch other sources ... take it out as you already have Tube flavor in the Dac

Wouldn't hurt or cost anything to give it a try ... Ditch the PL3 to and give it a listen

Nothing to add to the gain comments, I agree you simply have waaaaaaay too much.

Your speakers are begging for a low power SET amp like a 300B. Keep an idea on the classifieds and you can find a very nice 300B amp in the $1,000 range. A passive pre and an SET is my recommendation.

.

04-29-11: Davehrab
The PL3's output voltage is 5 volts as measured in a Stereophile review and way to much output for the DNA1's input stage.

With due respect for your well intended comments, I believe you are misinterpreting that spec. That number represents the output voltage at which the onset of clipping occurs, as indicated by a significant rise in distortion. The higher that number the better, everything else being equal. The actual output voltage at any instant of time will equal the input voltage multiplied by the gain that is provided by the preamp at the volume control setting being used (12db being the gain corresponding to the maximum setting of the volume control).

You can put a 10db attenuator at the amp's input or just remove the PL3 and drive the DNA1 from the Dac ... which has Tube output and a volume control.

If the PL3 is used, putting a 10db attenuator at the amp's input won't work well. Bass rolloff will result, as I indicated in my previous post. It also won't be a sufficient amount of attenuation.

Good point about the volume control on the DAC, though. Assuming it is the D1 model, I note that it also includes source switching, for both digital and analog sources. I don't know what its output impedance is, but if it is low enough to work well with an in-line attenuator, perhaps ditching the preamp AND putting a 10db attenuator at the amp inputs would do the trick. The OP might want to ask the DAC manufacturer what its worst case (maximum) output impedance is, across the audible frequency range.

If it were me, though, I would seriously consider Herman's suggestion of a 300B SET amp, or other low powered tube amp.

Regards,
-- Al