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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
grinnell
1,110 posts
 
lol i had a primaluna pl2 and ran it with the Ref 3A de Capos, plenty loud.

I know use a 4 watt decware mini torii, loud enough but not LOUD. 10wpc is plenty with these speakers
broadstone's avatar
broadstone OP
310 posts
 
Thanks, Grinnell. I really like these speakers and, so far at least, am pretty happy with the combination as described. I seldom listen at volumes that most would consider loud so, perhaps can keep the PL Prologue One. I currently have the preamp volume level set at 10 o'clock and the Prologue set at 9. Just to see what the results would be, I cranked the pre up to what I would call very loud. Because I heard no clipping, does this mean that the amp and speakers these speakers are compatible? I know that there are features built into their later models which make them somewhat more desirable but I'm wondering if there is any significant sonic difference.
almarg's avatar
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almarg
9,670 posts
 
Hi Jim (Broadstone),

I think I may have mentioned in one of your past threads that if the sensitivity of your Reference 3A speakers is comparable to that of the Reference 3A MM de Capo BE, per the measurements for that speaker shown here the 91 dB figure may be optimistic by around 5 dB or so.

Nevertheless, for solo guitar recordings, and for a considerable majority of recordings in most genres, I would certainly be surprised if the 35 watt capability of your amp proved to be insufficient.

A point to keep in mind is that what is usually the most significant factor in determining how much power is required is not volume or perceived loudness per se, but the dynamic range of the music that is being listened to. Meaning the DIFFERENCE in volume between the loudest notes and the softest notes, with well recorded minimally compressed classical symphonic music generally being one of the most demanding genres in that respect.

Many and probably most "pop" recordings, for example, are compressed to dynamic ranges of less than 10 db, which means that less than 10 times as much power will be required to reproduce the loudest notes as will be required to reproduce the softest notes. While many classical symphonic recordings will have dynamic ranges in the vicinity of 30 db (requiring 1,000 times as much power to reproduce the loudest notes compared to the softest notes), or in a few cases even more than 50 db (requiring 100,000 times as much power to reproduce the loudest notes compared to the softest notes; and no, that is not a typo).

For example, I have more than a few well engineered classical symphonic recordings in my collection which when played at modest average volumes of 75 db or so at my listening position, with the softest notes being in the 50 to 60 db area, will reach brief dynamic peaks of 100 to 105 db at the listening position. So most of the time the amplifier is putting out tiny fractions of a watt when playing those recordings, but brief dynamic peaks will require a great many watts.

From a subjective standpoint, though, loudness tends to be perceived based on the average volume of the music, not on the basis of brief dynamic peaks that may last for only a fraction of a second. Bear that in mind when considering Grinnell's comments.

Finally, with respect the 10 o'clock and 9 o'clock level settings you mentioned, keep in mind that those settings don't necessarily imply very much with respect to power. The relation between volume control settings and volume levels relates more to the gains and sensitivities of the equipment than to the maximum power and maximum volume capabilities of the equipment.

Best regards,
-- Al
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