Class D amps

[geezin']

I'm currently using a Topping PA3s to drive my Heresy 1 and KG SW sub. I like the stark nature of the pairing. It's clean a bit bright and very detailed. The passive sub I use does a good enough job for me as I'm not a big thumping bass fan. My hearing (trails off after 12kHz) may be why. Most of my listening is streaming via Spotify. All this has me intrigued if a significant improvement can be had by stepping up to a higher end/spec class D power amp. It'd be nice if I could keep it under $1K USD. Listen to just about anything. Rap and country are very rare other than that I'm old and tired of the same old same old. I expanded my listening to keep me from hating the music that drew me in in the first place.

 

So would it be money well spent? I forgot to mention I'm a cheap bastid thus will relentlessly hunt down a deal. Quality second hand is no problem to me.

[The Dude]

At that price range I believe you might have more options other than Class D, but if Class D is a must, check out Hypex Fushion. 

 

https://www.buckeyeamp.com/shop/amplifiers/hypex/nc502mp/2_channel

[derrickdj1]

The speaker is around 96 db sensitivity and can take up to around 100 watts. The price for Hypex class D amp is good but, look at the power ratings.  The speaker will never live to see that much power: 350 watts for 8 ohm speaker.  I love class D amps witch are very clean.  Some people use tube amps with their Heresy speakers.  A lot of the tube amps used are SE and less than 12 watts.   A class D amp or another type of amp may give you a slightly different sound but, better is in the eye of the beholder.

[parlophone1]

DIY Xypex nc400 mono blocks fall roughly in that category.

Not sure if you will hear significant improvement. I have them and they are what you described above: clean, a bit bright and very detailed. Some say that having two power supplies (one in each monoblock) result with better performance than integrated amp. You can give them a try.

 

[The Dude]

7 hours ago, derrickdj1 said:

The price for Hypex class D amp is good but, look at the power ratings.

I didn't actually compare all the specs between the topping and Hypex, but I'm not recommending the Hypex for the wattage, I recommending the Hypex for the quality. As you stated, better is in the eye of the  beholder, I just pointed him in the direction at what he can get for his budget. 

 

I agree with the tube statement, my favorite to-date has been the Scott 222 I once owned. Next inline is my Nelson Pass ACA at 8 watts SE SS, hard to beat for the price.

[flatgrass]

In the not too distant past I remember seeing a fair amount of discussion on VTV amplifiers.

 

https://vtvamplifier.com/vtv-purifi/

[hanksjim1]

Although these don't come up for sale often, I have had really good results with a used 100 watt/ch Emerald Physics 100.2SE on Khorns, LaScalas and Heresy speakers.

 

RCA and balanced XLR inputs, bridgeable mono switch...dead quiet and velvet smooth.

 

Here's a typical price:

 

https://reverb.com/item/62529416-emerald-physics-100-2se-stereo-power-amplifier

[the real Duke Spinner]

What,I see from Class D.is they are fine up to rated power That's all you get without nasty sound

 

Tube amps can he pushed hard and still sound good

[geezin']

1 hour ago, the real Duke Spinner said:

What,I see from Class D.is they are fine up to rated power That's all you get without nasty sound

 

Tube amps can he pushed hard and still sound good

 

 

I am definitely not going down that road. Spent the past 40 years or so screwing with things for a living. These days I buy what does the job I need it to w/o upgrades high maintenance and troubles. Tube amps are not for me. Not sure I'd wanna deal with class A heat. 

 

Thanks for all the answers and information. Seems like I get watts for dollars from what I can tell. Don't really seem to need 'em. The Topping measures 27 watts at 8Ω. I do use it like a power amp turned all the way up using a preamp for volume. Something to think about.

[CWelsh]

25 minutes ago, geezin' said:

 

 

I am definitely not going down that road. Spent the past 40 years or so screwing with things for a living. These days I buy what does the job I need it to w/o upgrades high maintenance and troubles. Tube amps are not for me. Not sure I'd wanna deal with class A heat. 

 

Thanks for all the answers and information. Seems like I get watts for dollars from what I can tell. Don't really seem to need 'em. The Topping measures 27 watts at 8Ω. I do use it like a power amp turned all the way up using a preamp for volume. Something to think about.

I also have an ACA and highly recommend it. I tried a Class D amp and thought it was fine, but I think the ACA is a whole lot better. And, it really doesn't get very hot. After all, it is only pumping out 8 watts maximum, and you're never going to get there with your Klipsch...maybe 1-2 watts. Of course, it is a kit, but I'm sure you can find one already built if you look. Still, if you're happy with your Topping, you can just leave well enough alone.

[JMeader]

I have 1987 klipsch La Scalla's in a 17 X 17 room with high ceilings and have driven them by

 

Crown   XLS 1002

Two-channel, 350W @ 4Ω Power Amplifier

 

and now by a Decware  Zen Torii Jr V2  https://www.decware.com/newsite/TORIIJR.html   20 watts

 

Sound out of my La Scalla's is great with both and I think you can enjoy your system with either tube or non tube. The Crown amp never went past 1/4 volume the the Decware less than half

 

I think a good quiet Pre amp will make either sound better, I use a Schiit Audio Freya S ( no longer available ) and using a XLR connection between the two is recommended

 

Enjoy the Music

 

 

[geezin']

6 hours ago, JMeader said:

I have 1987 klipsch La Scalla's in a 17 X 17 room with high ceilings and have driven them by

 

Crown   XLS 1002

Two-channel, 350W @ 4Ω Power Amplifier

 

and now by a Decware  Zen Torii Jr V2  https://www.decware.com/newsite/TORIIJR.html   20 watts

 

Sound out of my La Scalla's is great with both and I think you can enjoy your system with either tube or non tube. The Crown amp never went past 1/4 volume the the Decware less than half

 

I think a good quiet Pre amp will make either sound better, I use a Schiit Audio Freya S ( no longer available ) and using a XLR connection between the two is recommended

 

Enjoy the Music

 

 

Thanks. I'm just kicking the idea of moving up around.

On 3/7/2024 at 6:27 PM, CWelsh said:

I also have an ACA and highly recommend it. I tried a Class D amp and thought it was fine, but I think the ACA is a whole lot better. And, it really doesn't get very hot. After all, it is only pumping out 8 watts maximum, and you're never going to get there with your Klipsch...maybe 1-2 watts. Of course, it is a kit, but I'm sure you can find one already built if you look. Still, if you're happy with your Topping, you can just leave well enough alone.

Leave well enough alone? Sure that's always an option.  😉

[hellis739]

Good morning to everyone. Since the beginning of the year, my Klipsch Forte III are powered by a class D Hypex  2*250W (8ohm) and I can honestly admit that the speakers never performed better in the past. Compared to the class AB 2*50 (high quality) amp I used for the past 15 years, now there is a completely different (neutral) tonality ,much more detail in high frequencies and absolutely controlled lows. Make no mistake. The Forte ,the Cornwall and the Heresy speakers may be efficient according to the specs but their (12'' or 15'') woofer is conventional and not a horn. This means that they need power (the peak power according to specs is 400 W and not 100)  and class D provides VFM power. You can have the same result using a powerful AB or A class quality amp (such as Accuphase, McIntosh etc)  but not for the same cost.

[CWelsh]

2 hours ago, hellis739 said:

Good morning to everyone. Since the beginning of the year, my Klipsch Forte III are powered by a class D Hypex  2*250W (8ohm) and I can honestly admit that the speakers never performed better in the past. Compared to the class AB 2*50 (high quality) amp I used for the past 15 years, now there is a completely different (neutral) tonality ,much more detail in high frequencies and absolutely controlled lows. Make no mistake. The Forte ,the Cornwall and the Heresy speakers may be efficient according to the specs but their (12'' or 15'') woofer is conventional and not a horn. This means that they need power (the peak power according to specs is 400 W and not 100)  and class D provides VFM power. You can have the same result using a powerful AB or A class quality amp (such as Accuphase, McIntosh etc)  but not for the same cost.

So, I ask a sincere question...not to stir controversy, but out of ignorance on my part. My question starts with the fact that my 8 wpc amplifier will drive my Forte IIIs to what I consider an almost painful SPL. And, I make the assumption that a speaker that is not biamped will have the same amount of power going to the conventional woofer, and the mid and high frequency horns. Am I wrong in my thinking? I can maybe see that higher wattage can provide better control (damping?) of the woofer, but I'm not sure I understand how, exactly. Does the amplifier class (A vs. AB vs. D) have something to do with it?

[hellis739]

16 hours ago, CWelsh said:

So, I ask a sincere question...not to stir controversy, but out of ignorance on my part. My question starts with the fact that my 8 wpc amplifier will drive my Forte IIIs to what I consider an almost painful SPL. And, I make the assumption that a speaker that is not biamped will have the same amount of power going to the conventional woofer, and the mid and high frequency horns. Am I wrong in my thinking? I can maybe see that higher wattage can provide better control (damping?) of the woofer, but I'm not sure I understand how, exactly. Does the amplifier class (A vs. AB vs. D) have something to do with it?

Being equally or even more ignorant, I just wanted to contribute to your discussion with my experience. It might be more beneficial for someone instead of getting involved in an endless technical dispute, to go the other way round and do a test powering the speakers with a powerful (at least 100W/ch) amp. Of course ,if you are certain that your Forte perform according  to their full potential powered by a 2* 8W amp with any type of music  then you do not need to do any test at all. But I think that we should not confuse the gain and the SPL with the power of an amplifier. The transformation of my speakers is much more "obvious" when listening to music at low volumes. 

[opnly bafld]

@hellis739

 

Did you compare a 50W (or even less) class D amp to your 50W class AB amp?

Did you compare the amps mentioned over time switching back and forth between the 2?

 

[hellis739]

38 minutes ago, 83 LSIs said:

@hellis739

 

Did you compare a 50W (or even less) class D amp to your 50W class AB amp?

Did you compare the amps mentioned over time switching back and forth between the 2?

 

No, there was no reason for me to go back and forth because the impact of the replacement was obvious. The last 4 years (since the time I bought my Forte III) I was trying to figure out how to get rid off some kind of resonance which I had initially attributed to the wooden floor and generally my living room or the placement.  I always had hoped that changing into a more powerful amp could  help so after reading several reviews of class D amplifiers , I decided to buy the Hypex and connect it directly to my RME ADI 2. Now there is no resonance, it is like everything is more clear and detailed.

[CWelsh]

6 hours ago, hellis739 said:

Being equally or even more ignorant, I just wanted to contribute to your discussion with my experience. It might be more beneficial for someone instead of getting involved in an endless technical dispute, to go the other way round and do a test powering the speakers with a powerful (at least 100W/ch) amp. Of course ,if you are certain that your Forte perform according  to their full potential powered by a 2* 8W amp with any type of music  then you do not need to do any test at all. But I think that we should not confuse the gain and the SPL with the power of an amplifier. The transformation of my speakers is much more "obvious" when listening to music at low volumes. 

A key part of my question that I may not have articulated well is, regardless of the amps rated power, how much of that power is used to drive the speakers to an equal SPL?

 

There was a thread sometime back where a simple method of measurement was described that identifies just how many watts are actually being used to drive the speakers to the desired level. If an equal two amps with significantly different power ratings can drive the amp to the same level, it makes sense to me that the same wattage is being used to do so. And, if that is the case and you are noticing obvious benefits from the higher power amp, I have to wonder if the benefits are from something other than the actual power at the speaker terminals.

 

Please understand, I am not questioning or disputing your experience...others in these forums have said similar things. I'm just wondering if there are factors other than just the power capabilities of the amp that make the difference, or if that extra wattage contributes to more than just the power used by the speakers.

[the real Duke Spinner]

On 3/7/2024 at 5:57 PM, geezin' said:

 

 

I am definitely not going down that road. Spent the past 40 years or so screwing with things for a living. These days I buy what does the job I need it to w/o upgrades high maintenance and troubles. Tube amps are not for me. Not sure I'd wanna deal with class A heat. 

 

Than

I have had my QuickSilver tube amp for 23 years

Still on original tubes No repairs ever. ,🙄

[geezin']

There's always one.  🙄   Not interested regardless.