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 4 responses by pani

Pani,
I would think the 25 watt First Watt amplifier is a very good match with your speakers.I doubt that you'd be disappointed given your listening preferences.
Charles,

Yes Charles, considering that at the moment I use a Wavac 300B amp which I love to the core, except for its 10 watts power rating, I guess the F5 would be a more suitable transition for me. On the other hand, some have suggested that I go with one of the big McIntosh amps, like the MC452. With 450 watts on tap, probably it will be a experience in itself. But then Wavac - First Watt - Naim - McIntosh seems to be too wide a palate. I have to narrow it down.
Lots of interesting suggestions. Few points worth mentioning:

1. I already have a Naim NAC 52 preamp. So adding a NAP 300 would not be an issue from the matching stand point.

2. Bombaywalla, thanks for your suggestions. Somewhere within, I know a high powered is always desirable for this speaker. But I am at a stage where I am unable to find an amp with a good balance of quality - quantity - cost. The tube vs SS battle is also on. After listening to the Wavac for the past few months, I am getting too critical of less than stellar sound from an SS amp. But then finding a neutral, high-resolution tube amp isnt easy either.

3. Charles1dad, you are really fortunate to own a 14ohm speaker. That is a cake walk for these 300B SETs. I auditioned the Wavac on a pair of WHT speakers which were 11ohms nominal impedance. The wavac could drive it to rock concert levels. So, in a way you are pampered :-).

4. Islandman, your suggestion of changing the speaker has already been on my mind since last couple of months. I have been weighing all options. After a lot of research and introspection I came down to this:
The Wavac remains among the most accurate sounding amps I have ever heard. Near flawless, I would say. However it is like a tool, a very high precision one. Tannoy prestige speakers on the other hand are a work of art. They might have flaws but to me they remain one of the most satisfying/fulfilling speakers to listen to music on. Since the time I acquired it I stopped bothering about better speakers! I mean even when I hear a better speaker I do not care because this Tannoy doesnt let me worry. When I auditioned it, it was being driven by $1k chinese amp and even with that I was floored. This speaker remains the best purchase of all time in my audio journey. I just do not know what to replace this speaker with (except the higher Tannoys). Till that time I will keep it.

The problem at hand is to maximize the sound for the money. I have written to Reno hifi for the F5, lets see if I could get a demo. I am at Singapore btw, so the typical demo policy probably wont hold for me.
Atmasphere, I have never heard any of your amps before. I have only heard one OTL by Graaf and for some unknown reason I found it too coloured and bloated. However, I am trying to audition your amp here. Will report here if I get to hear them.

Charles1dad, I find it amusing that some westminister owners have complained repeatedly about their push-pull amps unable to control the bass of that speaker and then there are some who are ecstatic about them with puny SETs. I dont know that speaker well I guess.

Another amp that I may be considering is Ayon Crossfire III. It is a 30 watt SET built around AA62 tubes which are again derieved from 300B tubes. 30 watts of SET feels like a great proposal. Has anyone heard the Crossfire ?
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 ?