hypex amp over denon X4800H for very low impedance KEF Reference 1 Meta?

[Goldhamster916]

Hi,

i have the KEF Reference 1 Meta which drop to around 1.8 ohm in the subbase and i wonder if a dedicated amp (e.g. hypex) could improve the bass response compared to the denon x4800H avr they are currently running on.

Denon AVR-X4800H AVR Review

This is a review and detailed measurements of the Denon AVR-X4800H 9.4 home theater receiver. It was kindly drop shipped by a member and costs US $2499. While the look is the same as previous generations, the feel of the control knobs is much improved which I appreciate. Menu system is also...

www.audiosciencereview.com

bottom line is: the x4800h is a decent amplifier however i am not sure if it can handle that impedance drop around 40hz so well.

if i would benefit from a dedicated stereo amp, would a hypex Ncore hy252 stereo amp like this suffice?

SoundImpress HY252-2CH Stereo Verstärker | Ncore® | Powered by Hypex kaufen

Bestellen Sie den HY252-2CH online bei SoundImports ✓ Versand am selben Tag ✓ Kostenloser Versand

www.soundimports.eu

​

Any insights are much appreciated!

 

[ban25]

Are you running a stereo 2.0 setup or is this part of a larger multichannel system driven by the X4800H with subwoofers?

 

[Palmspar]

Red line dont drop under 3 ohm, the 4800 can handle that easy on normal listening levels.

 

[Goldhamster916]

Are you running a stereo 2.0 setup or is this part of a larger multichannel system driven by the X4800H with subwoofers?

It’s part of a 5.1.4 surround sound system which I also use for two channel music listening. So yes there is a subwoofer but I plan on having the speakers full range (with a equed drop under 35hz to protect the drivers) and room correction via Dirac art.

 

[Goldhamster916]

Red line dont drop under 3 ohm, the 4800 can handle that easy on normal listening levels.

The red line no. The EPDR yes.

 

[boXem]

The NC252MP is not the best choice for very low impedance speakers.

 

[ban25]

It’s part of a 5.1.4 surround sound system which I also use for two channel music listening. So yes there is a subwoofer but I plan on having the speakers full range (with a equed drop under 35hz to protect the drivers) and room correction via Dirac art.

Ah ok, so you are currently using every amp channel on the X4800H at this point. Yeah, I think there would be a benefit to running a 2 or 3 channel outboard amp for the front channels, especially if you intend to watch movies at reference volumes with ART.

I don't recommend running the Reference 1s down that low with ART. The F3 on those speakers is at 45 Hz so you don't want to be running them lower than that. The default calibration with ART will have them go down to 50 Hz.

 

[IngMishael]

Hi,

i have the KEF Reference 1 Meta which drop to around 1.8 ohm in the subbase and i wonder if a dedicated amp (e.g. hypex) could improve the bass response compared to the denon x4800H avr they are currently running on.

Denon AVR-X4800H AVR Review

This is a review and detailed measurements of the Denon AVR-X4800H 9.4 home theater receiver. It was kindly drop shipped by a member and costs US $2499. While the look is the same as previous generations, the feel of the control knobs is much improved which I appreciate. Menu system is also...

www.audiosciencereview.com

bottom line is: the x4800h is a decent amplifier however i am not sure if it can handle that impedance drop around 40hz so well.

if i would benefit from a dedicated stereo amp, would a hypex Ncore hy252 stereo amp like this suffice?

SoundImpress HY252-2CH Stereo Verstärker | Ncore® | Powered by Hypex kaufen

Bestellen Sie den HY252-2CH online bei SoundImports ✓ Versand am selben Tag ✓ Kostenloser Versand

www.soundimports.eu

​

Any insights are much appreciated!


View attachment 514455

yes but rather save up for the latest Hypex with better power supply or Purifi from boXem. better stability into lower EPDRs - Purifi 1ET6525SA or NCx500 Hypex

also don't bottom them out in DIRAC running them that low. I second setting it to its F3 or slightly higher

 

[Goldhamster916]

I have a very small room with a lot of room gain and the speakers are right against the front wall. I listen at 70DB max, thats why I plan to slope them down so low. But yes maybe a bit higher at 40hz or so.

I decided to definetely get a dedicated stereo amp. I was hoping to not have to spend more than 600. It’s hard for me to judge if I would actually hear a difference by spending more or not. Maybe the only way is to order and compare, although I don’t like that.

 

[wwenze]

The red line no. The EPDR yes.

First, a narrow dip is not as devastating as a wide dip

Second, there are many speakers with almost as low minimum EPDR. Look at Wharfedale 12.1 for example. Let's say the Wharfedale is 10% easier to drive. But it is also a much cheaper speaker so people use much cheaper amps than with KEF. And we never see people complaining about that.

Just because we now have EPDR doesn't mean older amps and speakers suddenly stop working. In fact you can argue that precisely these amps have long been driving speakers with EPDR lower than nominal impedance, it also proves that amps also have EPDR ratings lower / better than their own nominal impedance rating.

 

[Beave]

I have a very small room with a lot of room gain and the speakers are right against the front wall. I listen at 70DB max, thats why I plan to slope them down so low. But yes maybe a bit higher at 40hz or so.

I decided to definetely get a dedicated stereo amp. I was hoping to not have to spend more than 600. It’s hard for me to judge if I would actually hear a difference by spending more or not. Maybe the only way is to order and compare, although I don’t like that.

Then your Denon is probably sufficiently powerful.

 

[Head_Unit]

. I listen at 70DB max

Then I agree with @Beave you are nowhere near clipping, you have NO problem. Low impedance is only a problem at high volume when the amplification starts to run out of current.
OH but if you did get an amp it should have THREE channels, the center carries a lot as someone once posted data. And get an AC Infinity fan for your AVR, it will be a mercy.

 

[Goldhamster916]

First, a narrow dip is not as devastating as a wide dip

Second, there are many speakers with almost as low minimum EPDR. Look at Wharfedale 12.1 for example. Let's say the Wharfedale is 10% easier to drive. But it is also a much cheaper speaker so people use much cheaper amps than with KEF. And we never see people complaining about that.

Just because we now have EPDR doesn't mean older amps and speakers suddenly stop working. In fact you can argue that precisely these amps have long been driving speakers with EPDR lower than nominal impedance, it also proves that amps also have EPDR ratings lower / better than their own nominal impedance rating.

View attachment 514716

I appreciate the insight!

I did some more SPL measurements and sometimes I get peaks in the low 80’s DB range.

Then I agree with @Beave you are nowhere near clipping, you have NO problem. Low impedance is only a problem at high volume when the amplification starts to run out of current.
OH but if you did get an amp it should have THREE channels, the center carries a lot as someone once posted data. And get an AC Infinity fan for your AVR, it will be a mercy.

I appreciate your opinion, thank you!


I think at some point I will upgrade the 5.1.4 to a 7.1.4 system, since the denon can only amplifiy 9 channels I will need a stereo amp anyway.

would you agree that the NC252MP hypex amp will probably be enough with peaks in the low 80 DB range? The reference 1 meta are quite the high end speaker and I really don’t want to loose out on any performance for my needs in that room but I also don’t want to spend more than necessary.

Thank you all for helping out with your time and knowledge!

 

[Head_Unit]

would you agree that the NC252MP hypex amp will probably be enough with peaks in the low 80 DB range?

A 5 watt amplifier is probably enough ha ha! Seriously at those SPL I would just add on like a little Topping or something, save yer $$$$. But if you want to feel like headroom to spare or to crank it to 11 once in a while, get 3 channels for the LCR (or, due to the pairs nature of class D modules, 4 channels and one unused)