More power for KEF reference 5?

[soerenssen]

0.5W power consumption in standby??
The NCx500 consumes 18W per channel.

 

[Everett T]

I contacted KEF to ask for amp recommendations for the Reference 3 Meta and this is what they told me:
- they don´t have experience with NCx500 amps but they do have concerns about using Class D amps in this performance class - the Class D amps that they know sound a bit "cold and harsh"
- their recommendation was the Hegel 390 or 590 integrated amp
- ultimately, one should listen first and buy after listening

I haven't tested the speakers with the NCx500 yet, but I'm now considering opamps like Sparkos / Sonic Imagery - although @amirm 's review is putting me off a bit:

Discrete OpAmp Review: Sonic Imagery vs Sparkos

Recently I reviewed the Nord Three SE 1ET400A Dual Mono Stereo Amplifier. That unit came with the Sonic Imagery's 990ENH discrete operational amplifier ("opamp") in the buffer stage (pre-amplifier). The owner then ordered a set of Sparkos Pro SS2590 discrete opamps. This gave me a chance to...

www.audiosciencereview.com

I'm schocked they said this. Wouldn't think that Burno Putzey has a problem running class D in his Kii Three

 

[BrokenEnglishGuy]

1ET400A mono costs 740EUR, NCx500 mono cost 1060EUR.

I don't know the prices from EU, i import from EEUU and is kind of both have the price at 1100$-1200$~

Is not only the PCB cost 740 EUR?

 

[soerenssen]

I don't know the prices from EU, i import from EEUU and is kind of both have the price at 1100$~

Is not only the PCB cost 740 EUR?

AUDIOPHONICS MPA-M400ET Power Amplifier Class D Mono Purifi 1ET400A 1x400W 4 Ohm - Audiophonics

Class D mono power amplifier based on a PURIFI 1ET400A module and a HYPEX SMPS600A400 power supply.

www.audiophonics.fr

 

[BrokenEnglishGuy]

AUDIOPHONICS MPA-M400ET Power Amplifier Class D Mono Purifi 1ET400A 1x400W 4 Ohm - Audiophonics

Class D mono power amplifier based on a PURIFI 1ET400A module and a HYPEX SMPS600A400 power supply.

www.audiophonics.fr

thats the MONO purifi in the cheap case

AUDIOPHONICS HPA-S400ET Power Amplifier Class D Stereo Purifi 1ET400A 2x400W 4 Ohm - Audiophonics

Class D stereo power amplifier based on two PURIFI 1ET400A modules and a HYPEX SMPS1200A400 power supply.

www.audiophonics.fr

This is the

1ET400A​

This was was reviewed here, 1500 EUR~

Audiophonics HPA-S400ET Review (Stereo Amplifier)

This is a review and detailed measurements of the Audiophonics HPA-S400ET. It was sent to me by the company after member request and costs 1 490,00 € (US $1,638). I must say this is one of the best packaging of class D amplifiers (Purifi in this case) that I have seen! It is slick and has...

www.audiosciencereview.com

EDIT: Ah lmao you pointed these were the MONO, well i guess the cheap smaller case from the MONO purifi is fine (?) i don't know man im happy with my stereo purifi
EDIT2: i can't find the mono NCx500 from audiophonics, but the NCx500 is at 1400 EUR~

AUDIOPHONICS HPA-S600NCX Power Amplifier Class D NCore NCx500 2x600W 4 Ohm - Audiophonics

The Audiophonics HPA-S600NCX dual mono power amplifier, an updated and improved version of the HPA-S600NC, is now equipped with Hypex NCore NCx500 amplifier modules. These provide twice the performance in terms of distortion and output impedance

www.audiophonics.fr

 

[soerenssen]

thats the MONO purifi in the cheap case

AUDIOPHONICS HPA-S400ET Power Amplifier Class D Stereo Purifi 1ET400A 2x400W 4 Ohm - Audiophonics

Class D stereo power amplifier based on two PURIFI 1ET400A modules and a HYPEX SMPS1200A400 power supply.

www.audiophonics.fr

This is the

1ET400A​

This was was reviewed here, 1500 EUR~

Audiophonics HPA-S400ET Review (Stereo Amplifier)

This is a review and detailed measurements of the Audiophonics HPA-S400ET. It was sent to me by the company after member request and costs 1 490,00 € (US $1,638). I must say this is one of the best packaging of class D amplifiers (Purifi in this case) that I have seen! It is slick and has...

www.audiosciencereview.com

EDIT: Ah lmao you pointed these were the MONO, well i guess the cheap smaller case from the MONO purifi is fine (?) i don't know man im happy with my stereo purifi
EDIT2: i can't find the mono NCx500 from audiophonics, but the NCx500 is at 1400 EUR~

AUDIOPHONICS HPA-S600NCX Power Amplifier Class D NCore NCx500 2x600W 4 Ohm - Audiophonics

The Audiophonics HPA-S600NCX dual mono power amplifier, an updated and improved version of the HPA-S600NC, is now equipped with Hypex NCore NCx500 amplifier modules. These provide twice the performance in terms of distortion and output impedance

www.audiophonics.fr

Yes these are monos. Unfortunately Audiophonics doesn't make mono NCx500 amps.

 

[BrokenEnglishGuy]

Yes these are monos. Unfortunately Audiophonics doesn't make mono NCx500 amps.

Then just pick the mono purifi, audiophonics have good reputation here (?)

 

[soerenssen]

My only concern is the single PSU being a limitation in these stereo amps. I have an Audiophonics HPA-S600NCX here, but it will go back because it's not dual mono.

 

[BrokenEnglishGuy]

My only concern is the single PSU being a limitation in these stereo amps. I have an Audiophonics HPA-S600NCX here, but it will go back because it's not dual mono.

The PSU is 1500w, is a beefy PSU. To be honest a mono purifi like these are something for Blades or reference 5

 

[soerenssen]

KEF R7: 88dB, 250W, 3.2ohm
KEF Ref 3: 86dB, 300W, 3.2ohm
KEF recommends 60-110% of the power rating.
SMPS1200A700 is 1200W (slightly more with 230V here in Germany), and 325W continuous.
Sandu from soundnews is driving them with 2x bridged mono AHB2 (pure 500W at 4ohm).

Edit: it's no so much about the max. power, but rather the max clean power, with low, inaudible distortion.

 

[BrokenEnglishGuy]

KEF R7: 88dB, 250W, 3.2ohm
KEF Ref 3: 86dB, 300W, 3.2ohm
KEF recommends 60-110% of the power rating.

Yep, but remember i got -12dB

so is like 76dB@1W for my R7, lol. But i don't know how its work the efficiency if you down the preamp.

 

[BrokenEnglishGuy]

KEF R7: 88dB, 250W, 3.2ohm
KEF Ref 3: 86dB, 300W, 3.2ohm
KEF recommends 60-110% of the power rating.
SMPS1200A700 is 1200W (slightly more with 230V here in Germany), and 325W continuous.
Sandu from soundnews is driving them with 2x bridged mono AHB2 (pure 500W at 4ohm).

And remember, the purifi is 425w@1%. And in mono is like what? 800w-1kW? xD thats why im saying these mono are for ref5/blades

 

[soerenssen]

Btw, I'm with you regarding the Audiophonics amp. This larger case is really nice and robust, with heat sinks on both sides, large holes on the top and at the bottom. It's really a pity that it has only a single PSU.

 

[BrokenEnglishGuy]

Btw, I'm with you regarding the Audiophonics amp. This larger case is really nice and robust, with heat sinks on both sides, large holes on the top and at the bottom. It's really a pity that it has only a single PSU.

I remember there was a dual mono build from audiophnics, i dont see them. Maybe you can send a email to audiophonic to see if they can make a mono purifi with the nice case and separate box for mono.. i don't know! just ask them.
Edit: i don't recommend to put these dual psu in that case... i mean is not very standard.. is better separate box and mono if you want absurd amount of power with no problems, i mean.. its a 1500w tank ..

@Audiophonics ?

 

[quattro98]

The volume setting one uses largely depends on the gain in the system (source, preamp/processor, amp). A lower power amplifier can be made to have more gain and vice versa, so this isn't really indicative of amplifier power.

 

[soerenssen]

I remember there was a dual mono build from audiophnics, i dont see them. Maybe you can send a email to audiophonic to see if they can make a mono purifi with the nice case and separate box for mono.. i don't know! just ask them.
Edit: i don't recommend to put these dual psu in that case... i mean is not very standard.. is better separate box and mono if you want absurd amount of power with no problems, i mean.. its a 1500w tank ..

@Audiophonics ?

Yes, the idea is to have 2 completely separate mono block. That would pretty much guarantee that the speaker is not underpowered in any circumstances and even after a speaker upgrade (if I cannot make the KEFs sound right with this amp).

 

[SvanTeK]

I own a pair of AUDIOPHONICS MPA-M400ET. The sound is harsh and a ringing, it's simply very bad. I don't understand that amplifiers that measure so good sounds so bad.

 

[soerenssen]

I own a pair of AUDIOPHONICS MPA-M400ET. The sound is harsh and a ringing, it's simply very bad. I don't understand that amplifiers that measure so good sounds so bad.

Did you try with other amps?

 

[Willem]

This is indeed a largish room, particularly with the open end. My Quad 2805s cannot handle more than the 2x140 watt from the Quad 606-2 power amp, but they felt a little bit strained (in a larger room). What helped was a high pass filter and three subwoofers. In your case, that could be an alternative strategy to get more headroom.

 

[HarmonicTHD]

This is indeed a largish room, particularly with the open end. My Quad 2805s cannot handle more than the 2x140 watt from the Quad 606-2 power amp, but they felt a little bit strained (in a larger room). What helped was a high pass filter and three subwoofers. In your case, that could be an alternative strategy to get more headroom.

Yep.

Most of the Reference speakers have their lowest impedance around 40ish Hz plus minus (at least mine Ref 3 has). Offloading this area to active subs is a very good strategy, even more for reasons of room mode minimization. I use 2 subs (KEF 92s) crossed at 80Hz

(I also have “strong” power amps (380W into 4ohm), but it is debatable if I would really need them, if the SPL requirements are not too high).