Stereo integrated amp to pair with Dynaudio Special XXVs

[UCrazyKid]

What makes you think th Denon is not adequate for driving the Dynaudios? Take a look at the measurements. Surely it has lower distortion then what is produced by the speaker, and noise isn't excessive. It produces 114 watts into 8 ohms, do you think that will not be enough? It has a good room correction system and subwoofer outputs which will further improve sound quality.

The Special 25 (and Dynaudio’s in general) are not easy to drive speakers. They are a 4 ohm load with a sensitivity of 88db. They use aluminum wire voice coils. They thrive on high current amplifiers and lots of headroom.
The Denon AVR is a mass market unit that is not even rated for 4 ohms in their own specifications. It is driving 9 channels of amplification from a single power supply that fits into a small cabinet that is packed with PCBs for all the bells and whistles of the latest surround sound HDMI switching and video scaling. There is no information from Denon or in Amir’s review about the amplifiers current ratting or how big its capacitor storage bank is. Amir even describes the unit as “light weight”, not usually characteristic of a large heavy powerful power supply.
I prefer simple and keeping to features I am going to use. If I were runing a single pair of Special 25’s as the OP asked about, I would have chosen a simple 2 channel, high current class a/b amplifier from a mid-fi or high-fi manufacturer. I would go with an external DAC if one is needed (there are many great ones reviewed here) and not spent money on 7 extra channels if amplification I don’t need, and all the DSP, surround settings and effects I will never use.
I have owned Dynaudio Audience 52SE, Contour s1.4 and now Confidence C1 Platinums (all two-way, ported bookshelf/stand mount speakers like the Special 25) and know they sound best with lots of dedicated power. With my confidence C1 P’s I was driving them with 225watts from a Musical Fidelity dual mono A3.2CR power amp and when moving to 450watts with an A308CR power amp there was a very clear improvement in bass response as the speaker had more current and powerful to manage the mid-woofers with.
I just think the $1300 could have been spent differently and resulted in better 2 channel sound from what is considered by many a “legendary” speaker that sold for $4800.

 

[TimW]

The Denon AVR is a mass market unit that is not even rated for 4 ohms in their own specifications.

Here is Amir's measurement of power output into a 4 Ohm load, both channels driven:

There appears to be some headroom left in the power supply as well:

It is driving 9 channels of amplification from a single power supply that fits into a small cabinet that is packed with PCBs for all the bells and whistles of the latest surround sound HDMI switching and video scaling. There is no information from Denon or in Amir’s review about the amplifiers current ratting or how big its capacitor storage bank is. Amir even describes the unit as “light weight”, not usually characteristic of a large heavy powerful power supply.

Yes a small power supply that limits power during multi-channel usage would be a shame, and noisy circuits in the cabinet could cause performance degradation. Thankfully we have Amir's measurements to determine how well this product performs:

There is less power available when more channels are used of course, but there could still be enough for the OP at their listening distance and desired volume level.

And here is the pre-amp performance coming from the HDMI input:

Certainly not as good as a dedicated USB DAC but It's about 10dB better in SINAD then the built in amplifier so good enough.

I prefer simple and keeping to features I am going to use. If I were runing a single pair of Special 25’s as the OP asked about, I would have chosen a simple 2 channel, high current class a/b amplifier from a mid-fi or high-fi manufacturer. I would go with an external DAC if one is needed (there are many great ones reviewed here) and not spent money on 7 extra channels if amplification I don’t need, and all the DSP, surround settings and effects I will never use.

That is your preference, but as far as audible performance goes, I see no logical reason for that preference. The OP seems to want some of the features provided by this AVR (surround sound) and the included DSP for subwoofer crossover and room correction will allow for better audible performance then without. This DSP seems to operate at 96 kHz so there is no audible frequency response variation.

 

[Matias]

Maybe this can interest you.
https://www.buchardtaudio.com/shop/i150

 

[AllCourtGuy]

@UCrazyKid, my reasoning is that with the 3700 I can also upgrade to a separate amp for the 25s later if I so choose.

@TimW, thanks for the support.
Signing off.

 

[MrPeabody]

The Special 25 (and Dynaudio’s in general) are not easy to drive speakers. ... I have owned Dynaudio Audience 52SE, Contour s1.4 and now Confidence C1 Platinums (all two-way, ported bookshelf/stand mount speakers like the Special 25) and know they sound best with lots of dedicated power. With my confidence C1 P’s I was driving them with 225watts from a Musical Fidelity dual mono A3.2CR power amp and when moving to 450watts with an A308CR power amp there was a very clear improvement in bass response as the speaker had more current and powerful to manage the mid-woofers with.

So, they all sounded better when used with a more powerful amplifier. I wonder, though, if this was true only with the weaker amplifier turned way up, or if this was true for ordinary, routine listening?

With the C1 Platinum's you moved from a 225 Watt amp to a 450 Watt amp (a difference of 3 dB) and you say you noticed a very clear improvement in bass response. Since you gave no indication that this difference that you heard was specific to exceptionally loud playback levels, the implication is that you heard this difference ordinarily, with routine listening. This isn't possible when the voltage supplied to the speaker is the same for both amps, so it follows that during ordinary, routine listening, the less powerful 225 Watt amp was routinely operating in a protection mode of some sort that diminished the bass in some way. Hmmm. If voltage clipping was occurring with the less powerful amp, the resulting distortion would increase the high frequency content to an extent that would eventually be apparent, but the reason why this would have made the bass better with the more powerful amp is not obvious. And if the explanation is not that the 225 Watt amp was clipping, but rather that this amp was routinely operating in some protection mode, this as well is curious, because the most likely sort of protection mode that would be used is where the gain is reduced in a manner that would limit the maximum volume but that wouldn't affect the frequency response.

You say that the more powerful amp had more current and power to manage the mid-woofers. The way you wrote this suggests to me that this is believed to be a routine phenomenon, i.e., an effect that applies regardless of the volume level or of whether the less capable amp with which it is being compared is operating in protection mode. And this, unfortunately, suggests that a speaker is able to benefit from the ability of the amplifier to supply more current than the speaker is actually drawing at the given peak voltage level and the given impedance of the speaker.

Suppose you went from the 450 Watt amp to a 900 Watt amp, adding another 3 dB. Do you think that the bass would improve some more, when listening at ordinary, routine volume level? If so, then how about a 1.8 megaWatt amp? Would the bass improve again? Would this effect ever come to an end, such that there would be no further improvement in the bass no matter how much more powerful the amp? What would determine when this would happen? And how does this particular effect, an improvement in bass with the more powerful amp when both amps are played at levels where neither clips and neither enters any kind of protection mode, happen at all?

 

[UCrazyKid]

So, they all sounded better when used with a more powerful amplifier. I wonder, though, if this was true only with the weaker amplifier turned way up, or if this was true for ordinary, routine listening?

With the C1 Platinum's you moved from a 225 Watt amp to a 450 Watt amp (a difference of 3 dB) and you say you noticed a very clear improvement in bass response. Since you gave no indication that this difference that you heard was specific to exceptionally loud playback levels, the implication is that you heard this difference ordinarily, with routine listening. This isn't possible when the voltage supplied to the speaker is the same for both amps, so it follows that during ordinary, routine listening, the less powerful 225 Watt amp was routinely operating in a protection mode of some sort that diminished the bass in some way. Hmmm. If voltage clipping was occurring with the less powerful amp, the resulting distortion would increase the high frequency content to an extent that would eventually be apparent, but the reason why this would have made the bass better with the more powerful amp is not obvious. And if the explanation is not that the 225 Watt amp was clipping, but rather that this amp was routinely operating in some protection mode, this as well is curious, because the most likely sort of protection mode that would be used is where the gain is reduced in a manner that would limit the maximum volume but that wouldn't affect the frequency response.

You say that the more powerful amp had more current and power to manage the mid-woofers. The way you wrote this suggests to me that this is believed to be a routine phenomenon, i.e., an effect that applies regardless of the volume level or of whether the less capable amp with which it is being compared is operating in protection mode. And this, unfortunately, suggests that a speaker is able to benefit from the ability of the amplifier to supply more current than the speaker is actually drawing at the given peak voltage level and the given impedance of the speaker.

Suppose you went from the 450 Watt amp to a 900 Watt amp, adding another 3 dB. Do you think that the bass would improve some more, when listening at ordinary, routine volume level? If so, then how about a 1.8 megaWatt amp? Would the bass improve again? Would this effect ever come to an end, such that there would be no further improvement in the bass no matter how much more powerful the amp? What would determine when this would happen? And how does this particular effect, an improvement in bass with the more powerful amp when both amps are played at levels where neither clips and neither enters any kind of protection mode, happen at all?

You are making a lot of assumptions here. No, same match listening levels of 87db peak at 5meters listening distance by RadioShack handheld meter. All other equipment remaining the same. Preamp is also Musical Fidelity (A3.2CR) (designed to be matched to their power amps) at about 1/4 volume position on dial. Now there are likely some design differences in the two amplifiers, but they are advertised as using the same basic circuit by the manufacturer.
Opinions were asked for by the OP on what would drive a Dynaudio Special 25 well. I shared my thoughts based on my 20 yrs as a user of various Dynaudio products of similar design. There was and is no intention of trolling anyone. If one doesn’t want opinions, one should not ask for opinions. I offered my experience that maybe more relevant than others based on a lot of experience with the speaker product asked about.
Is ASR be coming the church of ASR where anything deemed in contrast to a particular position or Amir’s reviews are chastised? SMH

 

[UCrazyKid]

@UCrazyKid, my reasoning is that with the 3700 I can also upgrade to a separate amp for the 25s later if I so choose.

@TimW, thanks for the support.
Signing off.

There is no need for you defend your decision to me. (I notice you have edited your response, thanks) There was no intent to troll you. Just sharing my thoughts as you solicited opinions by starting this thread. Enjoy your new system. And yes, you have lots of options available to you, that is the joy of this hobby.

 

[MrPeabody]

You are making a lot of assumptions here. No, same match listening levels of 87db peak at 5meters listening distance by RadioShack handheld meter. All other equipment remaining the same. Preamp is also Musical Fidelity (A3.2CR) (designed to be matched to their power amps) at about 1/4 volume position on dial. Now there are likely some design differences in the two amplifiers, but they are advertised as using the same basic circuit by the manufacturer.
Opinions were asked for by the OP on what would drive a Dynaudio Special 25 well. I shared my thoughts based on my 20 yrs as a user of various Dynaudio products of similar design. There was and is no intention of trolling anyone. If one doesn’t want opinions, one should not ask for opinions. I offered my experience that maybe more relevant than others based on a lot of experience with the speaker product asked about.
Is ASR be coming the church of ASR where anything deemed in contrast to a particular position or Amir’s reviews are chastised? SMH

The "church of ASR" is new to me. I'm perplexed by your mentioning Amir. So far as I know, Amir has never expounded similar concerns about specious beliefs that are concerned with the question of when and why greater amplifier power will be beneficial. As such it is peculiar that you have mentioned Amir.

Amplifiers are inherently dissimilar from power cable snake oil in that there is always the potential that the extra power will be used sooner or later. It is an unfortunate reality that this fact leaves open the door to chicanery that ultimately isn't very different from power cable snake oil. Because of this unfortunate reality, it is desirable for everyone who extols the virtues of exceptionally powerful amplifiers to take care that the reasons they give are correct reasons.