[David C.]

I’m shopping for an entry-level tube preamp to use with my non-LFP-V Sig 30.2 and my non-LFP-V volume-controlled Sig 70.2s, and I’m considering the PrimaLuna ProLogue Three. Here are the specs:

Freq. Response: 4Hz-85kHz +/- 3dB
Gain: 11.5dB
THD: Less than 1% at full power
S/N Ratio: 109dB unweighted
Input Sensitivity: 200mV
Input Impedance: 100k Ohms
Output Impedance: 2.8k Ohms
Power Consumption: 48 watts
Tube Compliment: 2 - 12AX7, 2 - 12AU7, 2 - 5AR4
Dimensions: 11" x 7.5" x 15.5" (WxHxD)
Weight: 23.5 lbs
Inputs: 4 pair RCA
Outputs: 2 pairs of pre-amp outputs + tape monitor out

Does anyone know if this works well with RWA gear? The gain is nice and low (11.5 dB), but the output impedence is a tad high (2800 Ohms). I’m wondering if I’d have to get Vinnie to remove the volume controls from my amps before I could use the PrimaLuna.

[Vinnie R.]

Hi David,

Consider this:

You don't really need more voltage gain with your RWA non-LFP-V amps, but I'm sure you are looking for a remote volume control, and a few inputs to select from, and you mentioned you want tubes.

I recommend you consider the upcoming Signature 15 LFP-V Edition.  If you order before the end of this month, it's $1350.  It gives you 3 inputs, remote volume control, and the RCA outputs pass from the tube stage (current buffer), and it's all powered via the internal LiFePO4 battery.  It also has a Class AB output stage that will really knock your socks off (probably making you want to sell your older 30.2 non-LFP-V  ).  Feed that into the 70.2s for mo' power!

http://www.audiocircle.com/index.php?topic=98262.0


If you decide on the PrimaLuna 3, the gain should be fine.  You can set the volume control on your RWA amps to work best with the PL3, and then use the PL3 as the preamp (volume control and input select switch).

Best regards,

Vinnie

[wilsynet]

The high output impedance of the PrimaLuna @ 2.8K ohms may be problematic.  Some people say at least 10x but others say at least 20x.  The 30.2 integrated is 50K ohm input impedance, so about 18x.  Just enough or not quite enough depending on how you want to look at it.

[Vinnie R.]

The high output impedance of the PrimaLuna @ 2.8K ohms may be problematic.  Some people say at least 10x but others say at least 20x.  The 30.2 integrated is 50K ohm input impedance, so about 18x.  Just enough or not quite enough depending on how you want to look at it.

Good point!

If you have the older stepped attenuator volume control, the
input impedance is 20k.  With the motorized Alps Blue
Velvet (continuous), it is 50k.

Definitely look for at least a 10x factor on the impedances
that wilsynet mentioned above.

[David C.]

Both my amps have stepped attenuators with 20k input impedance, so it doesn’t sound like the PrimaLuna would work that well with them.

On the other hand, using a SIG 15 as a preamp is a terrific, cost-effective alternative, especially in light of the current 10% promotion. Thanks for the suggestion Vinnie; that’s probably what I’ll do.

David