25 watts Class A or 70 watts Class A/B ?


I understand these days there are many good examples of both Class A and Class A/B amps. To the point that a well designed Class A/B can beat a similar pedigree Class A amp. However my question is in particular related to these two amps:

1. First Watt F5 (Pass Labs)
2. Naim NAP 300

The speaker to be driven is a Tannoy dual concentric Turnberry SE. It is a 93 db sensitive 8 ohm load and in general considered to go well with both high powered and low powered amps.

F5 is a highly purist class A 25 watts design with a robust power supply. It is a push-pull design so it can generally drive difficult loads better than typical single ended first watt models (F3, F4 etc). I have heard the F5 on an Altec horn system and I loved its pure and direct sound.

Naim amps in general has always appealed to me, again because of their very direct presentation. Music has a certain excitement and bounce through them. The NAP 300 is one of their top models and I am sure it will be a very refined amp.

However I will only buy one. Both these amps must be having few fundamental differences in the way they present music considering they are coming from very different designers. Even the topology is different here.

The first question here is, can a 25 watts F5 drive the Tannoys well ? My room size is 200 sqft and I listen to music at reasonably medium to loud levels. I dont play very loud though. I listen to all kinds of music from Mozart to Metallica.

Qualitatively, sound per sound, how do these two amps compare ?
pani

Showing 2 responses by bombaywalla

Abhi,
from my experience it is not correct to think that just because a speaker is of high(er) efficiency that a low(er) power amplifier will do the job.
I have a Tannoy studio monitor that is 94dB SPL/W/m & I use it with a 120W/ch class-AB amp with very good effect. This studio monitor is, well..........., used in studios where the power amplifiers are of 100s of watts & often even 1000s of watts. The max wattage handling capacity of my speakers is 350W/speaker even tho' it's rated a 94dB SPL/W/m. To me this in itself is a huge hint from Tannoy to me that my speaker will do very well with a high power amp despite its high efficiency.
A higher power amp with a Tannoy will give you more control over the music & a lot more dynamic headroom. You music will sound alive as there will be plenty of wattage on-tap for dynamics.
I would try to find an excellent 100W/ch power amp for this Turnberry SE speaker. Maybe Pass' own offerings or some well regarded 100W tube amp.....

I tend to agree with Chayro - NAIM gear seems to sounds its very best with associated NAIM components. The magic falls off the cliff once you put a NAIM component with some other brand. IMHO. YMMV. Have you heard NAIM gear mixed-matched with other non-NAIM gear? If yes, did it have the same magic as with all-NAIM gear?

So, Peter, what's the deal here (just trying to understand this for myself) - you have PBN Audio manuf loudspeakers & also several amplifiers & then you have Liberty Audio also manuf some power amps??
How does Liberty Audio compare to PBN Audio? Is Liberty Audio the down-market brand?
Thanks.