Choosing between the Denon X8500H, X6700H, X4700H and X3700H (Updated)

[peng]

Peng, Using your calculator I got just under 108 db based on assumption that a 4500 or 4700 might be making 80wpc with all 5 channels driven.
As I (we) get further into the weeds between the 4500 and 4700, as long as both have Audyssey HT32, and Bluetooth head phone capability I couldn't care less about any other wireless connections or zone capabilities the 4700 may have that the 4500 does not. Again (sorry for being so dogmatic) but it looks to me like the audio signal processing, power, and distortion levels are identical between the two. Is that correct?

You are being very conservative to use 80 W, practically speaking, you won't have to worry about 5 ch peaking at the same time.

Is the108 dB for one speaker?

 

[JonfromCB]

You are being very conservative to use 80 W, practically speaking, you won't have to worry about 5 ch peaking at the same time.

Is the108 dB for one speaker?

Thanks Peng, good to know I was being conservative. The 108Db was for 5 speakers entered into the calculator. L/C/R are 4ohm, 92Db, Ascend Acoustics towers/Horizon with RAALs and L/R surrounds are 8ohm 87Db Ascend 200s. Should be plenty of juice from a 4700 don't you think?

Unless someone here tells me otherwise, I think I'm going to go pick-up a 4700 this afternoon. I got a killer-diller deal over the phone a short while ago with a military discount so there's no point in considering a 4500 based on what you and others have shared with me over the last couple
of hours.

 

[peng]

Thanks Peng, good to know I was being conservative. The 108Db was for 5 speakers entered into the calculator. L/C/R are 4ohm, 92Db, Ascend Acoustics towers/Horizon with RAALs and L/R surrounds are 8ohm 87Db Ascend 200s. Should be plenty of juice from a 4700 don't you think?

Unless someone here tells me otherwise, I think I'm going to go pick-up a 4700 this afternoon. I got a killer-diller deal over the phone a short while ago with a military discount so there's no point in considering a 4500 based on what you and others have shared with me over the last couple
of hours.

For 4 ohm speaker, it would be 105 dB, and for one speaker it would be about 98 dB, that's still loud enough for many, too loud for me already.

i think the 4700 is the sweet spot.

 

[Dj7675]

Peng, Using your calculator I got just under 108 db based on assumption that a 4500 or 4700 might be making 80wpc with all 5 channels driven.
As I (we) get further into the weeds between the 4500 and 4700, as long as both have Audyssey HT32, and Bluetooth head phone capability I couldn't care less about any other wireless connections or zone capabilities the 4700 may have that the 4500 does not. Again (sorry for being so dogmatic) but it looks to me like the audio signal processing, power, and distortion levels are identical between the two. Is that correct?

The 3700 tests out at 100w with 5 channels driven. I would expect the 4700 to do a bit better.

 

[Scubaduderon]

You got me curious, which Martin Logans model?

Prodigy, very big, very loud, and tough on amps. Older, but the magic is still there in every way.

 

[bo_knows]

Thanks, I took a look and found that it has slightly higher THD+N than the AVR-X4700H. I think the Emo amp would help if the user needs the extra juice. For me, it doesn't matter how powerful my amps are, I really only need 0.5 W most of the time with peaks to may be 50 W. So my 225 W amp just sit there like idling most of the time.

Not a lot of home audio applications need a lot of juice, its the short burst/peaks that needs it though. Still for a lot of people, the 100 to 120 WPC AVRs could be sufficient. And of course, big towers with low impedance, higher phase angles are the important things to consider when figuring out if an external high power amp is needed.

Here are photos I took (had to wait a long time for the peaks), when a pair of Mc1.2kW were driving the original Blades, it never peak higher than 120 W approx.

Hi Peng,

Thank you for sharing this.
So I can conclude that in this case, even benchmark ahb2 would have sufficent power to drive the big blades (200W in 4 ohm load).

 

[peng]

Hi Peng,

Thank you for sharing this.
So I can conclude that in this case, even benchmark ahb2 would have sufficent power to drive the big blades (200W in 4 ohm load).

It absolutely depends on the seating distance, maximum spl required at the seating positions.

The Blade (the big one) specs:

Impedance: 4 Ohm, 3.2 Ohm minimum
Sensitivity: 91 dB 2.83 V, 1 meter

The small Blade is the same except 1 dB less sensitive.

So calculations shows the SPL for 100 W at various distance as follow, assuming 3 dB room gain, and on per speaker (one) basis:
Note: assuming 3 dB room gain for all distances, there is no way of knowing exactly what it would be for your room.

4 meters...................98.9 dB
3 meters...................101.4 dB
2 meters...................105 dB

So for me, the AHB2 would have plenty for the big one. As far as I know @RichB use it to drive his Revel Salon2 that is as hard to drive or slightly worse than the Blade, and he seems fine with his set up.

Again, it depends.. If money is not an issue though, get two for bridging and you will have more than enough head room for sure, and for any kind of music.

In that demo room, it never peaked much above 120 W but as I mentioned, we were listening at near reference level but not quite, may be about 95 to 100 dB peak, from about 4 meters, and it was stereo so SPL would feel probably 3 dB louder anyway.

 

[peng]

Prodigy, very big, very loud, and tough on amps. Older, but the magic is still there in every way.

Well then I would agree those online spl calculator will not work well because its impedance is 4 Ohm nominal but 1 Ohm minimum that is far from any "norm". The reason is, the power requirement for a given SPL would be just highly dependent on the test signal frequency.

https://www.stereophile.com/content/martinlogan-prodigy-loudspeaker-measurements

On a separate note and on a different topic:

Stereophile did say in their review, "Fortunately, even with wideband media like SACD and DVD-Audio, there is very little energy in this frequency region, so the partnering amplifier will not be required to drive much power into this low impedance. "

Believe it or not, my old Denon AVR-3805 could actually drive those speakers in my smaller room sitting say 3 meters from a pair of those, because I typically listen to about 70, with peaks to 80 dB most of the time, occasionally higher. At such low level, that AVR could survive the combination of low impedance and negative phase angles at 8 kHz. Note that AVTech measured a lot of AVRs in the early years but the only ones that I could recall getting a "Pass" grade in their 1 Ohm test were the Denon AVR-3805 through 4308, none of those so called high current Haman Kardon or NAD's did.

That's just for argument sake, of course the big Prodigy should be paired with very robust power amps that are rated down to 2 ohms and with tons of heat sinks. Though again, truly 4 Ohms rated amps can do the job too if you sit close enough and stay well clear of the "reference level" territory.

 

[bo_knows]

It absolutely depends on the seating distance, maximum spl required at the seating positions.

The Blade (the big one) specs:

Impedance: 4 Ohm, 3.2 Ohm minimum
Sensitivity: 91 dB 2.83 V, 1 meter

The small Blade is the same except 1 dB less sensitive.

So calculations shows the SPL for 100 W at various distance as follow, assuming 3 dB room gain, and on per speaker (one) basis:
Note: assuming 3 dB room gain for all distances, there is no way of knowing exactly what it would be for your room.

4 meters...................98.9 dB
3 meters...................101.4 dB
2 meters...................105 dB

So for me, the AHB2 would have plenty for the big one. As far as I know @RichB use it to drive his Revel Salon2 that is as hard to drive or slightly worse than the Blade, and he seems fine with his set up.

Again, it depends.. If money is not an issue though, get two for bridging and you will have more than enough head room for sure, and for any kind of music.

In that demo room, it never peaked much above 120 W but as I mentioned, we were listening at near reference level but not quite, may be about 95 to 100 dB peak, from about 4 meters, and it was stereo so SPL would feel probably 3 dB louder anyway.

Thank you for this detailed explanation and I fully understand there is a lot of factors that need to be considered.
This is where I would land in my scenario (with KEF R500) : 2.4 meters...................105-106 dB. I usually listen to music at the 75-85db range and those peaks at 100+ would be extremely loud. I cherish my hearing and how I spend my money.

 

[RichB]

Thank you for this detailed explanation and I fully understand there is a lot of factors that need to be considered.
This is where I would land in my scenario (with KEF R500) : 2.4 meters...................105-106 dB. I usually listen to music at the 75-85db range and those peaks at 100+ would be extremely loud. I cherish my hearing and how I spend my money.

100 watts should be sufficient. I use this calculator and found that in corner to be the most accurate when compared to my measurements, though my speakers are not jammed in the corners.
http://myhometheater.homestead.com/splcalculator.html
Here are the estimates for 90 dB efficient speakers are 8 feet (2.4 meters) with near wall (even more conservative).

I expect that a single AHB2 (180 WPC into 4 ohms) should have no problem. There accurate clip indicators per channel so you can absolutely know if you need more power.

I have posted a procedure to use your processor that requires an SPL meter at 2.83 volts and measuring. Without repeating that here, with digital signals at 0 dBFS, it is possible to determination the maximum volume settings on a dB scale processor before clipping.

With my Salon2s, -10 requires 256 watts per channel. This is recording independent. No matter what I am listening to, -10 on my processor will not clip my amps. The AHB2 clip indicators do not light when tested with typically compressed music.

There are other aspects of amplification, noise, distortion into load, linearity into load, build quality, weight, heat, clip indication that all lead me to the AHB2s and I am thoroughly pleased.

Here are Martin Logins paired with AHB2s at AXPONA:

https://benchmarkmedia.com/blogs/reviews/ahb2-marting-logan-esl-11a-axpona-2019-theaudiobeatnik-com

Note: the ABH2 is 180 WPC into 4 ohms and in corners is a better match for most placement. That provides over 3 dB of headroom. In fact, with those selected the calculator shows 114 dB which may be beyond the capabilities of most speakers and even when not, not all all frequencies.
Also, at 75 dB my system is using less than 1/4 watt so performance below 1 watt is critical.

- Rich

 

[Bello]

Thank you for this detailed explanation and I fully understand there is a lot of factors that need to be considered.
This is where I would land in my scenario (with KEF R500) : 2.4 meters...................105-106 dB. I usually listen to music at the 75-85db range and those peaks at 100+ would be extremely loud. I cherish my hearing and how I spend my money.

Human factor, I determine power output by how much of a headache I have after

Usually, I'm way below the db level, unless I'm torture testing my amp

Fun fact- many moons ago, I worked as a band roadie w/ full band gear, very large amps. If I didn't lose my hearing back then, I think I'm fine with Emotiva / Denon's power

It's all good.... as long as you don't lay your ear on a speaker at full power, I'd say you're fine

 

[bo_knows]

100 watts should be sufficient. I use this calculator and found that in corner to be the most accurate when compared to my measurements, though my speakers are not jammed in the corners.
http://myhometheater.homestead.com/splcalculator.html
Here are the estimates for 90 dB efficient speakers are 8 feet (2.4 meters) with near wall (even more conservative).

View attachment 85176

I expect that a single AHB2 (180 WPC into 4 ohms) should have no problem. There accurate clip indicators per channel so you can absolutely know if you need more power.

I have posted a procedure to use your processor that requires an SPL meter at 2.83 volts and measuring. Without repeating that here, with digital signals at 0 dBFS, it is possible to determination the maximum volume settings on a dB scale processor before clipping.

With my Salon2s, -10 requires 256 watts per channel. This is recording independent. No matter what I am listening to, -10 on my processor will not clip my amps. The AHB2 clip indicators do not light when tested with typically compressed music.
View attachment 85177

There are other aspects of amplification, noise, distortion into load, linearity into load, build quality, weight, heat, clip indication that all lead me to the AHB2s and I am thoroughly pleased.

Here are Martin Logins paired with AHB2s at AXPONA:

https://benchmarkmedia.com/blogs/reviews/ahb2-marting-logan-esl-11a-axpona-2019-theaudiobeatnik-com

Note: the ABH2 is 180 WPC into 4 ohms and in corners is a better match for most placement. That provides over 3 dB of headroom. In fact, with those selected the calculator shows 114 dB which may be beyond the capabilities of most speakers and even when not, not all all frequencies.
Also, at 75 dB my system is using less than 1/4 watt so performance below 1 watt is critical.

- Rich

Hi Rich,

Thank you very much for your response.
I've used the same calculator and with KEF R500 (sensitivity 87dB) came to 105-106dB SPL. Speakers will do 112dB SPL (not sure at what distance and at what frequency).
My Denon AVR H8500H has even more absolute power than ABH2 in 4 ohms but it's not as nearly clean hence my interest in ABH2 for the front channels. Like you said: "using less than 1/4 watt so performance below 1 watt is critical".

 

[Scubaduderon]

Well then I would agree those online spl calculator will not work well because its impedance is 4 Ohm nominal but 1 Ohm minimum that is far from any "norm". The reason is, the power requirement for a given SPL would be just highly dependent on the test signal frequency.

https://www.stereophile.com/content/martinlogan-prodigy-loudspeaker-measurements
View attachment 85170

On a separate note and on a different topic:

Stereophile did say in their review, "Fortunately, even with wideband media like SACD and DVD-Audio, there is very little energy in this frequency region, so the partnering amplifier will not be required to drive much power into this low impedance. "

Believe it or not, my old Denon AVR-3805 could actually drive those speakers in my smaller room sitting say 3 meters from a pair of those, because I typically listen to about 70, with peaks to 80 dB most of the time, occasionally higher. At such low level, that AVR could survive the combination of low impedance and negative phase angles at 8 kHz. Note that AVTech measured a lot of AVRs in the early years but the only ones that I could recall getting a "Pass" grade in their 1 Ohm test were the Denon AVR-3805 through 4308, none of those so called high current Haman Kardon or NAD's did.

That's just for argument sake, of course the big Prodigy should be paired with very robust power amps that are rated down to 2 ohms and with tons of heat sinks. Though again, truly 4 Ohms rated amps can do the job too if you sit close enough and stay well clear of the "reference level" territory.

Thank peng for your reply.

I've got the Prodigies on an Aragon 8008bb. It's definitely a powerhouse, with lots of big heat sinks, totalling a hefty 77 pounds. Its got two 1,100kVa toroidal transformers in a dual mono configuration feeding a total a bank of caps measuring 140,000uf. The amp doubles down, and is very robust indeed. It's not the most expensive amp, but is definitely a high bang for the buck contender.

I love these speakers, the soft is great, but loud is definitely where they excell.

So you see my dilemma. Mixing these into a home theater that will do these speakers justice when listening in 2 channel mode. Im hoping these Denon AVR's preamps and DACS do them justice. I'll know soon enough.

I'm also considering switching between the AVR as a pre for the HT and a Topping DAC and matching headphone amp as a pre, for an incredibly clean setup. What are your thoughts on that?

 

[peng]

Thank peng for your reply.

I've got the Prodigies on an Aragon 8008bb. It's definitely a powerhouse, with lots of big heat sinks, totalling a hefty 77 pounds. Its got two 1,100kVa toroidal transformers in a dual mono configuration feeding a total a bank of caps measuring 140,000uf. The amp doubles down, and is very robust indeed. It's not the most expensive amp, but is definitely a high bang for the buck contender.

I love these speakers, the soft is great, but loud is definitely where they excell.

So you see my dilemma. Mixing these into a home theater that will do these speakers justice when listening in 2 channel mode. Im hoping these Denon AVR's preamps and DACS do them justice. I'll know soon enough.

I'm also considering switching between the AVR as a pre for the HT and a Topping DAC and matching headphone amp as a pre, for an incredibly clean setup. What are your thoughts on that?

That amp should be fine for the Prodigies.

The manual says: Power Handling 300 watts per channel Recommended Amplifier Power 80 - 300 watts per channel.

Your amp can do 400 W into 4 Ohms, perfect!! Those Denon AVR have no trouble outputting 2 volts at >95 dB SINAD and that would be more than enough to drive your Aragon to its rated output into 4 Ohms. The Denon's preout SINAD would be at least 15 dB better than the Aragon, so that's again, perfect!! I mean in terms of doing the power amp "justice".

 

[Scubaduderon]

That amp should be fine for the Prodigies.

The manual says: Power Handling 300 watts per channel Recommended Amplifier Power 80 - 300 watts per channel.

Your amp can do 400 W into 4 Ohms, perfect!! Those Denon AVR have no trouble outputting 2 volts at >95 dB SINAD and that would be more than enough to drive your Aragon to its rated output into 4 Ohms. The Denon's preout SINAD would be at least 15 dB better than the Aragon, so that's again, perfect!! I mean in terms of doing the power amp "justice".

Thank you once again, two more questions,

What is the Aragons SINAD? I found a calculator but am unclear how to use it. I know its signal to noise ratio is 110db and thd is .06% and it has +-70v rails. It was my impression that the Aragons are held in good regard. No Pass Labs equivalent for sure, but not junk either. Should I buy a better amp because the Aragon is holding the Prodigies back? They sound incredible to me.... Super clean and smooth with no graininess unless cranked to ridiculous levels...

 

[peng]

Thank you once again, two more questions,

What is the Aragons SINAD? I found a calculator but am unclear how to use it. I know its signal to noise ratio is 110db and thd is .06% and it has +-70v rails. It was my impression that the Aragons are held in good regard. No Pass Labs equivalent for sure, but not junk either. Should I buy a better amp because the Aragon is holding the Prodigies back? They sound incredible to me.... Super clean and smooth with no graininess unless cranked to ridiculous levels...

As you know:
SINAD is signal to noise and distortion, unit is in dB
THD is total harmonic distortion, usually in dB or %, THD+N is total harmonic distortions plus noise

Obviously THD+N = 1/SINAD as a ration, so in dB, that is log form, SINAD will be numerically the same as THD+N but a negative number because log₁₀(X) = - log₁₀(X)

You can use the sengpielaudio.com calculator to convert dB to %, if you are used to %.

http://www.sengpielaudio.com/calculator-thd.htm

You can use it to convert both ways, dB to % or % to dB. Below is an example, if you pick 0.06% as the THD, in dB the answer would be -64.44 dB, so in SINAD it will be -(-64.4 dB), or 64.5 dB.

You Aragon 8008BB seems like a great amp for your speakers. It's THD spec is 0.04% (-67.96 dB) but that is for 2-20,000 Hz, and at rated output so it is not fair to compare that number with THD measured at 1 kHz at rated output.

Note that the Aragon 0.04% is for THD, not THD+N. It would be higher if noise is included depending on how "quiet" the amp is, how much higher we do not know. I supposed it would be too heavy, therefore expensive, to send it to ASR for bench test?

I am quite sure if your amp is in top shape, it is not holding back your Prodigy speakers, or any speakers.

 

[peng]

They sound incredible to me.... Super clean and smooth with no graininess unless cranked to ridiculous levels...

Found the Stereophile measurements of the 8008, not sure if it is the same as your 8008BB, if it is, of course it should be able to sound super clean and smooth, as long as the input signal to it is super clean, and that means the quality of the recording/mastering of the media contents has to be clean too.

https://www.stereophile.com/content/aragon-8008-power-amplifier-measurements

Fig.9 Aragon 8008, distortion (%) vs output power into (from bottom to top at 100W): 8 ohms, 4 ohms, and 2 ohms.

Freq response, square wave, cross talk all looked great too.

Below are the square wave measurements of the Aragon amp vs the Emotiva Gen3:
You can visually tell which one is more like a perfect square, whether the difference would result in any audible difference or not is a different story.

Fig.2 Aragon 8008, small-signal 10kHz squarewave into 8 ohms.


https://www.stereophile.com/content/emotiva-xpa-gen3-two-channel-power-amplifier-measurements

Fig.2 Emotiva XPA Gen3, small-signal, 10kHz squarewave into 8 ohms.

 

[Bello]

Thank peng for your reply.

I've got the Prodigies on an Aragon 8008bb. It's definitely a powerhouse, with lots of big heat sinks, totalling a hefty 77 pounds. Its got two 1,100kVa toroidal transformers in a dual mono configuration feeding a total a bank of caps measuring 140,000uf. The amp doubles down, and is very robust indeed. It's not the most expensive amp, but is definitely a high bang for the buck contender.

I love these speakers, the soft is great, but loud is definitely where they excell.

So you see my dilemma. Mixing these into a home theater that will do these speakers justice when listening in 2 channel mode. Im hoping these Denon AVR's preamps and DACS do them justice. I'll know soon enough.

I'm also considering switching between the AVR as a pre for the HT and a Topping DAC and matching headphone amp as a pre, for an incredibly clean setup. What are your thoughts on that?

I would proceed with caution, if the Aragon 8008bb had been sitting or in use for many years. I would call Aragon to find out what the shelf life of the 140,000uf Electrolytic capacitors. These larger capacitors will eventually fail / slowly begin to produce feedback, over time. Typically 10-20 yrs / depending in usage, stored climate ect...

Great setup!

Good luck!

 

[Scubaduderon]

I would proceed with caution, if the Aragon 8008bb had been sitting or in use for many years. I would call Aragon to find out what the shelf life of the 140,000uf Electrolytic capacitors. These larger capacitors will eventually fail / slowly begin to produce feedback, over time. Typically 10-20 yrs / depending in usage, stored climate ect...

Great setup!

Good luck![/QUOTE

Thanks for the advi e

I would proceed with caution, if the Aragon 8008bb had been sitting or in use for many years. I would call Aragon to find out what the shelf life of the 140,000uf Electrolytic capacitors. These larger capacitors will eventually fail / slowly begin to produce feedback, over time. Typically 10-20 yrs / depending in usage, stored climate ect...

Great setup!

Good luck!

Thanks for the advice Bello. Ive been playing that amp daily for about ten years and its still going strong. A few years back I had it checked out by Sybesmas, the suggested repair facility for her, and they gave her a clean bill of health. I actually have 2 Aragons. I was biamping the Prodigies, but then I decided to add the surround back channels, so I pulled out a pair of Thiel CS3.6's from storage... I know, a totally different sound than the Prodigies, but another one of my favorites and I figure its better using them than not. Now those are another very hard speaker to drive, so I had to break up the biamp setup and use the second Aragon for the back channel.

My system has been even stranger. At one point I had a dual sub NHT X'd setup for my side channels. When my AVR calculated their distance, it added about 20 feet because they have active crossovers and their own computerized amp setup and its associated time delay was about equivalent to how long it takes sound to go 20 feet!

I guess I'm a bit of a speaker freak!

 

[Scubaduderon]

As you know:
SINAD is signal to noise and distortion, unit is in dB
THD is total harmonic distortion, usually in dB or %, THD+N is total harmonic distortions plus noise

Obviously THD+N = 1/SINAD as a ration, so in dB, that is log form, SINAD will be numerically the same as THD+N but a negative number because log₁₀(X) = - log₁₀(X)

You can use the sengpielaudio.com calculator to convert dB to %, if you are used to %.

http://www.sengpielaudio.com/calculator-thd.htm

You can use it to convert both ways, dB to % or % to dB. Below is an example, if you pick 0.06% as the THD, in dB the answer would be -64.44 dB, so in SINAD it will be -(-64.4 dB), or 64.5 dB.

View attachment 85509

You Aragon 8008BB seems like a great amp for your speakers. It's THD spec is 0.04% (-67.96 dB) but that is for 2-20,000 Hz, and at rated output so it is not fair to compare that number with THD measured at 1 kHz at rated output.

Note that the Aragon 0.04% is for THD, not THD+N. It would be higher if noise is included depending on how "quiet" the amp is, how much higher we do not know. I supposed it would be too heavy, therefore expensive, to send it to ASR for bench test?

I am quite sure if your amp is in top shape, it is not holding back your Prodigy speakers, or any speakers.

Thank you for the help. That was the calculator I found, I just missed that % sign to the right of THD and thought I'd have to do some conversions. Tech school math was a very long time ago for me....

I take it that all large power amps have somewhat similar sinads to the Aragon? In no way does it compare to the tiny headphone amps I see on this site.

I have the shipping boxes for both amps. Message me the address I will consider sending one to you. I guess it might add to the site to have some benchmarks from the stone age.

Thanks again,
Ron