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
Pani,
The Ayon Crossfire from your description could be an ideal match with your Tannoy. I hope you're able to listen to it and the Atma-sphere OTL as well. I've heard the M 60 and MA-1 numerous times and they're very good amplifiers. I just personally prefer what a good SET uniquely offers. Horses for courses.Once you compare them, one or the other will move you more. It just depends on what type of sound you want.
Charles,
Pass labs watts need to be X 5. when you go from A to B.

Naim and Pass Labs are so differently. Pass Labs is superior in depth and wide.

At shows with very extreme Naim stuff the stage was fully 2 dimensional. I had my music with me.

I played; light my fire from Jacintha. The cross flute in the beginning of the song was on the same line as her voice. In real it is about 3-4 metres behind her voice.

In my opinion depth and wide are essential parts for the absolute sound.

When you go back to a 2 dimensional stage you miss a lot of the exitement.

When I confronted the Naim people with these information. They did not know what to say.

An amp of 100 dollar also can give a 2 dimensional stage.

That is why I call 2 dimensional audio standard audio.

In 7 years of time I have done many comparisson between 2 and 3 dimensional sound.

All people prefered 3 dimensional sound far over 2 dimensional sound. Audio can sometimes be very simple and convincing.
Got in touch with Reno hifi and Srajan Eaben (6moons). Both of them highly recommended the upcoming F6 over the F5. The F6 is more powerful but it supposedly sounds more like a SIT too. So it is like the best of both worlds, power, transparency and finesse.

Anyone has heard about the F6 ?
Pani,

I would certainly not pass up on a chance to audition the Ayon Crossfire should you have a chance. If its 30 wpc is enough for your needs, based on my experience with the brand I am confident you would find it to be an excellent component in your system.

John
Hi Pani, as you can see from the impedance graph (linked), these 93db speakers are easy to drive with an impedance from 8ohm up, I myself with my taste in music would go for the FW F5, your Metallica discs may tax the F5 if you want to fill a bigger room than yours at very loud level.

Remember though, you will need a source or preamp that has higher than usual voltage output as the F5 only has 15db of gain, it has a very passive preamp friendly 100kohm input impedance, but you will need a higher than normal output source.

http://www.imagebam.com/image/1d79b6265107399

Cheers George