NAD C375BEE to drive Revel F208

[Nothingness]

Bear with me if this is a naive question. I’ve read great reviews about the Revel F208 and am wondering if my NAD C375BEE can drive them properly. The amp is rated at 150W per channel into 8 ohms, while the speakers are spec’d for 50–350W RMS. I rarely turn my volume past 10 o’clock, as I don’t need high loudness—but will my amp drive the speakers to perform at their full potential?

This leads me to a broader question: Can a lower-powered amp still be a good match for large speakers if I only listen at moderate volumes? What key concepts should I study to understand and choose a properly matched amp and speakers in terms of power?

Thanks.

 

[amirm]

Only you can answer that as we don't know how loud is loud for you. In these cases, I would buy the speaker and try it with the amp you have. If you turn up the volume to max and it still not loud enough, then you need a more powerful amp. Exception is if you have 300 to 400+ watt amplifier. That tends to be good enough for just about any system.

Note also that power rating at 4 ohm matters, not 8.

 

[Nothingness]

Only you can answer that as we don't know how loud is loud for you. In these cases, I would buy the speaker and try it with the amp you have. If you turn up the volume to max and it still not loud enough, then you need a more powerful amp. Exception is if you have 300 to 400+ watt amplifier. That tends to be good enough for just about any system.

Note also that power rating at 4 ohm matters, not 8.

Thanks for your response, Amir. From what I checked in the manual, the NAD C375BEE outputs 410W at 4Ω. Based on your answer, I assume that’s sufficient for the F208, which maxes out at 350W? As I mentioned in my first post, I only need moderate loudness and rarely turn my volume knob past 10 o’clock.

The reason I asked is that I’m curious whether a low-powered amp can drive high-power speakers to their full potential within a moderate loudness range. If not, does a lower-powered amp cause the speakers to lose some detail? That’s what I, as a novice, am wondering. I asked ChatGPT, which pulls information from various websites, including some "audiophile forums" and possibly some snake oil sellers, and it said no—small amps can’t fully utilize high-power speakers even within moderate loudness range. I am just not sure that it gave me an accurate answer, so that's why I asked here.

Also, thanks for your YouTube video on understanding speaker measurements. It was really helpful for me.

 

[amirm]

Thanks for your response, Amir. From what I checked in the manual, the NAD C375BEE outputs 410W at 4Ω. Based on your answer, I assume that’s sufficient for the F208, which maxes out at 350W?

That's ample power. So you should be good to go.

 

[amirm]

The reason I asked is that I’m curious whether a low-powered amp can drive high-power speakers to their full potential within a moderate loudness range.

Sure although it depends on your definition of low power. I think as long as you have 50+ watts, you can get most of the loudness you need. Beyond that, the amount of power you need grows exponentially.

 

[Nothingness]

That's ample power. So you should be good to go.

I think that’s the answer I needed.

Sure although it depends on your definition of low power. I think as long as you have 50+ watts, you can get most of the loudness you need. Beyond that, the amount of power you need grows exponentially.

I never took any physics classes beyond a few in high school, so I’m struggling a bit with this power thing.

Thanks again.

 

[Nothingness]

Sure although it depends on your definition of low power. I think as long as you have 50+ watts, you can get most of the loudness you need. Beyond that, the amount of power you need grows exponentially.

Oops, but again, the amp's manual informs that IHF dynamic power of 4ohms is 410W (and 2 ohms is 800W). Does that "IHF dynamic power" matter?

 

[Old_School_Brad]

As Amir mentioned, the 375BEE should be powerful enough. NAD has a history of designing their amplifiers to deliver significant dynamic power that exceeds their nominal rated specifications.

 

[DanielT]

Download a free db meter app. ..


Then measure at your listening position. Measure for a few minutes and you will see the average value. Then you will get an idea of your listening level. It largely determines your need for power. That plus if you listen to very dynamic music. Then you need amp power that can handle it.

From what I can see your speakers have around 88 dB sensitivity. IF you listen to let's say a level of 70 dB , with non-dynamic music if we are talking NAD amp then an old NAD 3020 with 20 watts would have fixed it easily. But IF, on the other hand, you sometimes want to push the pedal to the metal then a small power weak old NAD amp is not up to the job.

Revel F208 Tower Speaker Review

This is a review and detailed measurements of the Revel F208 speaker. It was kindly purchased by a member and drop shipped to me for measurements. Revel F208 costs $2,500 each or US $5,000 for a pair. Note: our company, Madrona Digital is a dealer for Revel speakers. Feel free to read as...

audiosciencereview.com

So it all depends on your needs, listening habits and music choices so to speak.

Edit:
Here's a tip. You can try it yourself. It gives you an indication of your needs.
In the amplifier headroom box, enter the value of how dynamic the music you are listening to is. Make sure you have headroom.
You don't need to worry too much about listening distance because it is important outdoors and not in a normal reflective listening room. Set two meters.

Crown Audio - Professional Power Amplifiers | English (US)

www.crownaudio.com

(subwoofers require much more power than some tweeters, but perhaps we should leave that discussion aside for now.)

 

[Nothingness]

I will try the app that you suggested, DanielT. Thanks for your help.

 

[DanielT]

I will try the app that you suggested, DanielT. Thanks for your help.

Test it out.

Regarding listening distance and and power requirements. IF you have an extremely, let's say, soundproofed room, it may be a factor to consider. However, in a "normal" furnished listening room, hardly so. In any case, you can easily investigate this with a db meter in your room. Place it at different listening distances and measure.

Edit:
About dynamics in music, here's a tip on a thread about it:

General question on dynamic range and music

I have a general question on dynamic range (DR). Redbook CD offers 16 bit, corresponding to 96dB DR. With dither up to 120dB. High-Res 24 bit audio even 144dB. Vinyl, according to different sources up to 70dB and tape machines roughly 65dB. On the other hand, recorded music has very limited DR...

audiosciencereview.com

Compressed music, without peaks, that is, punch stripped down, doesn't require much amp power. That in itself is good. What's sad is how it sounds:

 

[JeremyFife]

Nice speakers!

There's no difference between a very powerful amp idling and putting out 50W and a less powerful amp putting out 50W ... same watts.

Where it matters is when the amp reaches it's design limits, the more powerful amp will have an easier time for longer.

The F208s dip down to a lowish impedance (3.5Ohm, I think) which makes them more challenging to an amp ... the amp will reach it's design limits earlier than with easier speakers.

Long winded way of agreeing that if they sound good with your amp, and go loud enough, then your amp is just fine

Try it.

 

[Beave]

1. Speaker wattage ratings are just about meaningless. The maximum values they list are often well more than enough to fry the speakers. It's complicated and not easy at all to assign simple numbers for min or max power, but marketing departments like simple numbers, so that's what people get. It depends on the content being played (the frequency, the duration). The minimum power values, well, I'm not sure where they come up with those. 1 watt is enough to play your speakers at moderately loud levels.

2. That NAD amp is quite powerful and can probably play your speakers at ear-bleeding levels without too much problem. It's probably powerful enough to blow your speakers with certain musical content played really loud.

Conclusion: That amp is totally fine for normal use. If you turn it up so loud that you hear harshness or distortion, turn it down quickly before you blow something. Otherwise, enjoy the combination and don't worry about the power ratings.

 

[Nothingness]

Nice speakers!

There's no difference between a very powerful amp idling and putting out 50W and a less powerful amp putting out 50W ... same watts.

Where it matters is when the amp reaches it's design limits, the more powerful amp will have an easier time for longer.

The F208s dip down to a lowish impedance (3.5Ohm, I think) which makes them more challenging to an amp ... the amp will reach it's design limits earlier than with easier speakers.

Long winded way of agreeing that if they sound good with your amp, and go loud enough, then your amp is just fine

Try it.

That answers my question. Thank you.

But still, another novice question comes to mind. Am I understanding correctly that at 8Ω, my NAD C375BEE produces 150W per channel, and at 4Ω, it delivers an even higher power output of 410W? At 3.5Ω, as you mentioned, I assume it could reach around 500W (the manual states it generates 600W of IHF dynamic power at 2Ω).

So when you say "challenging," do you mean that at some point, the amp can no longer provide enough power to drive the speaker properly at lower impedance? Sorry if this sounds silly or too obvious, but I’m confused.

I add some specs for my amp, just in case.

 

[pjug]

If you turn it up so loud that you hear harshness or distortion, turn it down quickly before you blow something.

or use the soft clipping if you are playing loud enough that you are really worried about clipping.

 

[Beave]

or use the soft clipping if you are playing loud enough that you are really worried about clipping.

I was thinking more along the lines of the distortion/harshness coming from the speakers being overpowered, not from the amp running into clipping.

But yeah, if you do blast at volume 11, that might help prevent clipping.

 

[DanielT]

That answers my question. Thank you.

But still, another novice question comes to mind. Am I understanding correctly that at 8Ω, my NAD C375BEE produces 150W per channel, and at 4Ω, it delivers an even higher power output of 410W? At 3.5Ω, as you mentioned, I assume it could reach around 500W (the manual states it generates 600W of IHF dynamic power at 2Ω).

So when you say "challenging," do you mean that at some point, the amp can no longer provide enough power to drive the speaker properly at lower impedance? Sorry if this sounds silly or too obvious, but I’m confused.

I add some specs for my amp, just in case.

View attachment 434423

As others in the thread have pointed out. Your NAD C375BEE has more than enough power for your speakers. Put your hifi money elsewhere instead. A new comfortable listening chair, try a new music streaming provider, move the speakers around to see how it affects the sound, new thick carpet to dampen floor reflections, maybe try dampening side reflections to see if you like what it gives, try measuring with a microphone and then set a good FR via EQ and so on.

You might find these threads below interesting and useful?:

Perceptual Effects of Room Reflections

Perceptual Effects of Room Reflections By Amir Majidimehr [Note: This article was originally published in the Widescreen Review Magazine, titled "it is not simple!"] When Gary Reber asked me to write an article for the 20th anniversary of Widescreen Review magazine I was stumped at first...

audiosciencereview.com

Wood acoustic diffusers have become a decorative item - loved the idea!

Hi As an acoustician I am tired to tell people not to think room treatment only as absorption. In most small rooms absorption often creates more issues than it solves. Diffusion is a better solution. However, all I hear: they are expensive, ugly and difficult to place in a room. I am hence...

audiosciencereview.com

Or you can leave your hifi stuff as it is and just explore more music:
(of course you can do both)

Music Reviews and Discussions

audiosciencereview.com

 

[JeremyFife]

That answers my question. Thank you.

But still, another novice question comes to mind. Am I understanding correctly that at 8Ω, my NAD C375BEE produces 150W per channel, and at 4Ω, it delivers an even higher power output of 410W? At 3.5Ω, as you mentioned, I assume it could reach around 500W (the manual states it generates 600W of IHF dynamic power at 2Ω).

So when you say "challenging," do you mean that at some point, the amp can no longer provide enough power to drive the speaker properly at lower impedance? Sorry if this sounds silly or too obvious, but I’m confused.

I add some specs for my amp, just in case.

View attachment 434423

Not silly at all. I'm beginning to understand this, but I'm still learning.

When speakers present lower impedance (and that's not constant, varies with frequency and phase - I find that complicated) the amp needs to provide more current (amperes, not voltage) and that is difficult.
There is lower resistance, so it should be easier to drive, but that requires more current which is the problem.

Others here can explain it much better!

Your amp is probably fine

 

[Nothingness]

As others in the thread have pointed out. Your NAD C375BEE has more than enough power for your speakers. Put your hifi money elsewhere instead. A new comfortable listening chair, try a new music streaming provider, move the speakers around to see how it affects the sound, new thick carpet to dampen floor reflections, maybe try dampening side reflections to see if you like what it gives, try measuring with a microphone and then set a good FR via EQ and so on.

You might find these threads below interesting and useful?:

Perceptual Effects of Room Reflections

Perceptual Effects of Room Reflections By Amir Majidimehr [Note: This article was originally published in the Widescreen Review Magazine, titled "it is not simple!"] When Gary Reber asked me to write an article for the 20th anniversary of Widescreen Review magazine I was stumped at first...

audiosciencereview.com

Wood acoustic diffusers have become a decorative item - loved the idea!

Hi As an acoustician I am tired to tell people not to think room treatment only as absorption. In most small rooms absorption often creates more issues than it solves. Diffusion is a better solution. However, all I hear: they are expensive, ugly and difficult to place in a room. I am hence...

audiosciencereview.com

Or you can leave your hifi stuff as it is and just explore more music:
(of course you can do both)

Music Reviews and Discussions

audiosciencereview.com

Thanks for your reading recommendations. I now understand that my amp is powerful enough to drive the speakers, and I have no plans to spend money on a new one. But still, I am confused about how speakers and amps work together.

The thread about room acoustics reminded me of a friend from years ago. I had an entertainment room about 13' x 15', with the long wall completely covered with books from floor to ceiling. I also had racks of CD shelves and other stuff. It looked pretty cool. I designed the space that way because I love books and music, and that was the only way to store them in the house. I had a vague sense that it was great for music listening, but it wasn’t something I seriously thought about.

A friend once visited me and loved the sound of my system. I was running a NAD C352 driving a pair of B&W 603 S2. He was so impressed that he asked me to help him buy a similar setup. Similar, but not identical. He ended up getting a NAD C372 with 150W per channel and a newer pair of B&W speakers. But when I visited his place, he was puzzled—the sound just wasn’t great. Eventually, he moved house and sold the gear.

I wondered what made the difference between his system and mine. Was it the speakers? The amp? Something else? I suspected the speakers or maybe the room, but I was never sure.

Recently, I moved to a new city, and my current listening room has no books or CD shelves—it’s nearly empty, and the shape isn’t ideal. I don’t even need to say it, but the sound is awful. And just like that, it became crystal clear to me what truly made the difference between my setup and my friend’s: the room mattered the most.

Thankfully, my wife is moderately supportive—she just said I’m crazy for moving speakers around, reorganizing the furniture, and is completely against having a thick rug, as she thinks she might be allergic to one.

 

[Nothingness]

Not silly at all. I'm beginning to understand this, but I'm still learning.

When speakers present lower impedance (and that's not constant, varies with frequency and phase - I find that complicated) the amp needs to provide more current (amperes, not voltage) and that is difficult.
There is lower resistance, so it should be easier to drive, but that requires more current which is the problem.

Others here can explain it much better!

Ha, this is something new I’m learning. I thought it was because, at some point, the amp could no longer produce enough power to drive the speakers as the resistance dropped. But you said that the lower the resistance, the easier it is for the amp, which makes sense to me. But now, with the current coming into play, I’m even more confused.