Adding a power Amp for Evoke 50 to Cinema 40

[Willems]

Hello All,

I have been reading this forum for quite a while. I currently have a Marantz Cinema 40 with Evoke 50 front channels, Evoke 25C Center and Evoke 10 Rear Channels, additionally I Still have an SVS SB12-NSD subwoofer.

I sense that the Evoke 50 lack treble when playing through the Cinema 40 amp, which when reading reviews should not be the case. For example an extensive review from what hifi confirms the +/- 3 dB performance from the manufacturer. In my case the mid/high starts dropping quite a bit from 10 kHz onwards. My conclusion was that a more powerful amp would be able to correct this. Am I right with respect to this?

Then my journey started to find a poweramp for my situation, and I have been looking at the following products:

- Hypex Nilai 500 2x 250 watt 4 Ohm - Gain 21,75
- Audiophonics HPA-S400ET - 2 x 400 watt 4 ohm - Gain 26
- Audiophonics HPA-S600NCX - 2 x 600 watt 4 ohm - Gain 25

Now I have learned from the forum to check if the preamp output is enough to use the amplifier, and strangely the HPA-S400ET is not quite handy with the 26db gain, since this would mean that at 2 v pre-out it would produce 400 watt (full volume) which is exactly at the 82,5db out option of the amplifier (or 2,5 relative)

The HPA-S600NCX would reach full volume using 2,75volts which leaves some headroom, and the Nilai would need 2,57 so also has some headroom.
So based upon these figures I guess the HPA-S600NCX should be the one to go for, or am I missing something, or would it be better to go for the 250watt option with Nilai as the power is then more in line with the internal amps from the Cinema 40?

 

[JSmith]

For example an extensive review

WhatHiFi don't test anything, they're all paid reviews... the only "review" of note is this one here at ASR;

Marantz Cinema 40 AVR Review

This is a review and detailed measurements of the Marantz Cinema 40 9.4 channel AV Receiver (AVR). It is on kind loan from a member and costs US $3,500. As is typical in this class, you get a very large box. At least the look is unique and to my liking. The port hole display while limiting...

www.audiosciencereview.com

JSmith

 

[kyuu]

How did you determine that the treble is dropping from 10kHz and up? That's oddly specific without performing some measurements.

If you are experiencing a lack in the treble, it's not likely that a lack of power in the amp has anything to do with it. Higher treble is not where you need a lot of power. More likely you have an issue with your in-room response. My first guess would be that your bass and/or mid-range is overly accentuated causing the treble to sound recessed by comparison. Are you using any EQ or room correction?

 

[Chrispy]

Do you need a power amp particularly other than the treble "issue"? I'd say its more in your setup/speakers but you can correct/customize with eq, too (particularly Audyssey with the Editor App).

 

[Willems]

How did you determine that the treble is dropping from 10kHz and up? That's oddly specific without performing some measurements.

If you are experiencing a lack in the treble, it's not likely that a lack of power in the amp has anything to do with it. Higher treble is not where you need a lot of power. More likely you have an issue with your in-room response. My first guess would be that your bass and/or mid-range is overly accentuated causing the treble to sound recessed by comparison. Are you using any EQ or room correction?

When I use any mode of amplification I feel that the highs are too low. In Dirac it sets the curtain at 11khz, and the 20khz is way below the average volume of the rest of the sound. I know there is a dificult room mode in the room of 40Hz which is due to the width of the room being 6,30m.

In the picture a measurement without Dirac turned on the room mode of 40hz is troublesome and the peaks at 50 80 and 300 can be resolved with Dirac, however the drop off at the high end is what cocerns me now.

My idea is that the impedance of the speaker is the problem, it draws too much power on the low end so it drops off at the high end, the red line showing the impedance of the speaker. I heard Amir mentioning this in a review of the HPA-S400ET which is a sign of not enough power.

 

[Willems]

Do you need a power amp particularly other than the treble "issue"? I'd say its more in your setup/speakers but you can correct/customize with eq, too (particularly Audyssey with the Editor App).

If it is possible to correct with Audyssey of Dirac that would be even better a financially more attractive option However I feel that I have tried everything currently, And I cannot get it right with the current setup. Currently I am using the Storm audio target curve, which at the moment is the best could get, however I also feel that the mid range is fatiguing when playing internet radio, which is not an issue with Heos / DSD / Hi-res files.

 

[kyuu]

In the picture a measurement without diract turned on the room mode of 40hz is troublesome and the peaks at 50 80 and 300 can be resolved with Dirac, however the drop off at the high end is what cocerns me now.

View attachment 391782

Someone else who is more experienced can correct me if I'm wrong here, but that actually looks pretty normal for an in-room response. Asides from the 100-600Hz range being a bit recessed, the overall tilt of the frequency response is what you'd want and expect. But if the roll off the high treble like that is something you feel is an audible issue, the easiest and probably best solution would be using an EQ to apply a bit of boost to that range.

My idea is that the impedance of the speaker is the problem, it draws too much power on the low end so it drops off at the high end, the red line showing the impedance of the speaker. I heard Amir mentioning this in a review of the HPA-S400ET which is a sign of not enough power.

View attachment 391783

I looked through the review of the HPA-S400ET and I can't find what you're referring to? That impedance chart is a little unusual to my eyes, but the impedance isn't terribly high in the treble. Also, to my understanding, a higher impedance like that means the speaker is demanding less power from the amp, which makes a shortfall in amp power being an issue even less likely.

 

[JeremyFife]

More power will help with low frequencies, not treble.

Definitely look again at EQ, or speaker positioning.
Is there something about your room that could be causing problems - reflections, hard surfaces?

Good luck

 

[Old_School_Brad]

If it is possible to correct with Audyssey of Dirac that would be even better a financially more attractive option However I feel that I have tried everything currently, And I cannot get it right with the current setup. Currently I am using the Storm audio target curve, which at the moment is the best could get, however I also feel that the mid range is fatiguing when playing internet radio, which is not an issue with Heos / DSD / Hi-res files.

View attachment 391784

Why don't you just drag that curtain to 20k and assess it again?

 

[Willems]

Why don't you just drag that curtain to 20k and assess it again?

The curtain does not influence the measurement as Dirac places the curtain on top of the measured response, when measuring the curtain is not applicable so remeasuring is not necessary when the room or setup does not change.

 

[Willems]

More power will help with low frequencies, not treble.

Definitely look again at EQ, or speaker positioning.
Is there something about your room that could be causing problems - reflections, hard surfaces?

Good luck

We live in a fairly new house where we have a lot of hard surfaces and we are getting more furninture every time, so that will influence, however the quantity of high present is low now, so absorbing reflections will not increase high frequencies isnt it? And this is quite differen from what I hear at demos in other places

 

[Willems]

Someone else who is more experienced can correct me if I'm wrong here, but that actually looks pretty normal for an in-room response. Asides from the 100-600Hz range being a bit recessed, the overall tilt of the frequency response is what you'd want and expect. But if the roll off the high treble like that is something you feel is an audible issue, the easiest and probably best solution would be using an EQ to apply a bit of boost to that range.

I looked through the review of the HPA-S400ET and I can't find what you're referring to? That impedance chart is a little unusual to my eyes, but the impedance isn't terribly high in the treble. Also, to my understanding, a higher impedance like that means the speaker is demanding less power from the amp, which makes a shortfall in amp power being an issue even less likely.

With respect to the HPA review Amir discusses the response from the amp at 8 and 4 ohms where he gives the explanation that some designs struggle and start rolling off in the high frequencies or increasing in the high frequencies. As a result of the load that it has to perform. About at this point:

 

[Old_School_Brad]

The curtain does not influence the measurement as Dirac places the curtain on top of the measured response, when measuring the curtain is not applicable so remeasuring is not necessary when the room or setup does not change.

You can click and hold and drag it to the right.

 

[kyuu]

With respect to the HPA review Amir discusses the response from the amp at 8 and 4 ohms where he gives the explanation that some designs struggle and start rolling off in the high frequencies or increasing in the high frequencies. As a result of the load that it has to perform.

Ah okay. I believe at that point he is talking about the load dependency that some class D amps have when they don't use PFFB. Your Marantz does not use class D amps, and does not have load dependency. Its frequency response should be flat regardless of the impedance of the speaker.

 

[Willems]

Ok so the effecct of a demanding speaker is not an issue if I read the responses here.

However when going to the 2nd part of the question which of the amplifiers would be the best to add in this case. Since I feel the speaker needs more power to actually make it sing, it is a demanding speaker with a sensitivity of 87Db and quite a low impedance between 100 hz and 1khz, which amplifier would be the best companion, to this speaker then?

Hypex Nilai 500 2x 250 watt 4 Ohm - Gain 21,75
- Audiophonics HPA-S400ET - 2 x 400 watt 4 ohm - Gain 26
- Audiophonics HPA-S600NCX - 2 x 600 watt 4 ohm - Gain 25

Now I have learned from the forum to check if the preamp output is enough to use the amplifier, and strangely the HPA-S400ET is not quite handy with the 26db gain, since this would mean that at 2 v pre-out it would produce 400 watt (full volume) which is exactly at the 82,5db out option of the amplifier (or 2,5 relative)

The HPA-S600NCX would reach full volume using 2,75volts which leaves some headroom, and the Nilai would need 2,57 so also has some headroom.
So based upon these figures I guess the HPA-S600NCX should be the one to go for, or am I missing something, or would it be better to go for the 250watt option with Nilai as the power is then more in line with the internal amps from the Cinema 40?