Transitioning from SS to tube amplification


Except during my early years in this hobby when monaural and vacuum tubes were the only choice, I've always used solid state amps and, mostly, electrostatic and ribbon panels. Recently, I bought a 20+ year old pair of good stand mount monitors (Reference 3A Serie MMC) that sounded very good with my solid state Peachtree pre and power amps so I thought it would be a good time to also try a vacuum tube amp in lieu of the many challenges associated with pairing tubes with my Martin Logan electrostatics speakers.

I started with a borrowed entry level but well reviewed Primary Luna Prologue One integrated amp paired with the Peachtree Audio Nova integrated as the preamp. I chose this combo because of the Peachtree's source input choices as well, of course, to use its remote control.

Because most of my listening is to various genres of solo guitar that's what I used to audition this combo. My first impression was mixed in that the sound seemed, at first, somewhat attenuated as if the strings had been muffled with a piece of cloth having been laid on the fret board. On the other hand, the sound was very pleasing with some of the jagged edges rounded off. Overall, and regardless of which might be argued as sounding most realistic, I'm very satisfied with what I'll call its more relaxed presentation. I like it and will very likely stay with the tubes.

Please don't read this as my support of one technology over another; first, I'm not qualified to make recommendations. Also, I'm 73 years old and have become more sensitive to certain sounds especially from percussive sources, so this becomes a factor in music choices as well as equipment.

Now that I've decided to stay with tubes, what I would like advice on is where to go next. I like this Prima Luna very much but have been advised by several whose advice I've learned to trust, that at 91dB these speakers may not be sensitive enough to get the best from the A3. I suppose what this means is that I need to look into another amp or more efficient speakers.
128x128broadstone
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Yes, Al, I took your previous explanation to heart and found that the best example of dynamic range in my favorites collection Is I n the overture from Tannheuser relative to the relatively quiet lead in to the overwhelming brass. The range in this case, using an SPL meter, was about 50 dB starting at about 48. With the current setting on the Prologue the max volume is about 103 for this piece which is way more than I could take for very long. However, it sounded pretty accurate. Also, I reviewed the charts you referred to and the sensitivity is substantially lower than advertised and consistent with your previous comments. It's a disappointment but I can get by with it until I decide where to go next. I'm impressed with what Ive read about other PL amps and am tending toward staying with this manufacturer with one or another of their models, perhaps a dedicated power amp. For the music and volumes that I most listen to the current setup is quite satisfying. BTW, the mention of the clock dial setting was part of what the previous owner recommended to avoid clipping. In messing with various settings and volumes I've not been able to hear any so far.

Delay, thank you and I'm sure what you're saying makes good sense to those who have a better technical understanding of these things but I need a little more explanation to get my head around it. Also, what makes it a little more difficult is the fact that, right or wrong, I've always avoided maxing any controls thinking that that was an area where undesirable things start to happen. One thing I tried was to take that setting up to about 3 o'clock on the Prologue and at one point in a fairly loud playback I got a somewhat boomy sound of a lower mid frequency. Lowering the pre strength cured the anomaly

Steakster, it's good to hear that you had success with a similar setup and I thank you for sharing it. The bottom line here, I suppose, is that I truly like both the MMC's and the Prologue but I want to maximize within the constraints of my budget, of course, and need to decide which component to concentrate on. The most obvious or practical solution may be to find a more sensitive speaker.
An excellent speaker to consider is made by Audiokinesis, the Zephrin. It is easy to drive and very revealing.

As you are no doubt aware, dollar for dollar tube power is more expensive than solid state (and even in the 1960s cost/profit was the main impetus behind the switch to transistors) so speaker efficiency is very important when dealing with tubes!
Broadstone:

Assuming your PL uses an Alps volume pot, turning it up to max will most likely offer the best sound as if will be the next best thing to removing it from the signal path completely.

I've done this with an Audion Silver Night integrated as well as with a Musical Fidelity X-A1 when adding a tube preamp to the integrated amps (neither had amp/out connections).

If you have ever used an integrated amp, or preamp with a tone control defeat switch the sonic benefits are similar.
Dekay, thanks, I understand now and it makes sense. Atmasphere, thanks for the advice but having just bought the ML Ethos speakers, the Reference 3 A's, and the Primaluna amp, I'm going to have to consider some less expensive fixes for awhile, at least.