Outlaw 5000 or Rotel 1555 if same price

[Leemix]

A lot of good detailed answers in this thread but even if only 5 channels used rerun auto setup so it matches subs and in case one channel is a little off, which is unlikly especially if no gain knobs on the power amp.

 

[Rick330]

Yeah I have 11 channels so I was going to run it again anyway. What a nice guy to take the time and answer so specific though.

 

[PENG]

A lot of good detailed answers in this thread but even if only 5 channels used rerun auto setup so it matches subs and in case one channel is a little off, which is unlikly especially if no gain knobs on the power amp.

Thank you, I forgot the sub channel. So for a 5.1 channel, it is a must to re-run auto set up, otherwise in the case of the Rotel amp, the bass would become a few dB hot.

 

[Leemix]

Thank you, I forgot the sub channel. So for a 5.1 channel, it is a must to re-run auto set up, otherwise in the case of the Rotel amp, the bass would become a few dB hot.

It would be well within what many increase it anyway so might just make his smile a little wider


Sent from my iPad using Tapatalk

 

[Rick330]

Thank you, I forgot the sub channel. So for a 5.1 channel, it is a must to re-run auto set up, otherwise in the case of the Rotel amp, the bass would become a few dB hot.

I use a marantz 7055 now which has a gain higher than the Rotel also. No big deal I run the calibration a lot anyway lol. The marantz is perfectly quiet during quiet scenes through the speakers.

 

[PENG]

I use a marantz 7055 now which has a gain higher than the Rotel also. No big deal I run the calibration a lot anyway lol. The marantz is perfectly quiet during quiet scenes through the speakers.

That's a 5 channel amp so with the Rotel you have 10 channels. Seems to me you need a M2200 if you are keeping the Marantz and want to avoid using the Denon's amp. What model is your Denon? You do know those two amps are not that much more powerful than any Denon models above the AVR-X3400H right? Also, depending on which model you have, there is something else about the pre out that you should know about.

 

[Rick330]

Yeah I'm going to sell the marantz 7055. Ive heard it will do fine with the new Martin Logan's but I feel better going with a beefy amp that says 4ohm minimum rather than the marantz which is 6ohm minimum. I am only going to use 3 channels for the front stage and let the Denon x3600 power the other 8 channels.

 

[PENG]

Yeah I'm going to sell the marantz 7055. Ive heard it will do fine with the new Martin Logan's but I feel better going with a beefy amp that says 4ohm minimum rather than the marantz which is 6ohm minimum. I am only going to use 3 channels for the front stage and let the Denon x3600 power the other 8 channels.

Okay then you should pay attention to what Gene said about the X3600H's amp assign feature.

"With the AVR-X3600H configured to reroute the main front L/R internal amplifiers, the preamp is physically disconnected from the power amp. This allows the preamp stage full capability of delivering up to 4Vrms unclipped when connected to external amplification as can be seen in the following output vs distortion plot courtesy of Sound United Engineering."

Read the full review here:

https://www.audioholics.com/av-receiver-reviews/denon-avr-x3600h

Another thing, don't underestimate the Marantz MM7055. Its amp is quite beefy, I would say for real world practical use it should be as powerful (if not slightly more than..) as the RMB-1555 two channel driven and slightly less under 5 channel driven conditions. You gain only 3 dB with 2X the power output so practically speaking the power output difference between the Marantz and the Rotel is completely negligible.

Take a look of the measurements in two different reviews on the 7055.

Marantz AV7005/MM7025/7055 (Test)

audiovision.de

Marantz AV7005 Surround Processor and MM7055 Amplifier HT Labs Measures

HT Labs Measures Marantz AV7005 Surround Processor Analog frequency response in Pure Direct mode: –0.05 dB at 10 Hz –0.00 dB at 20 Hz –0.01 dB at 20 kHz –0.07 dB at 50 kHz Analog frequency response with signal processing: –0.45 dB at 10 Hz –0.13 dB at 20 Hz –0.14 dB at 20 kHz

www.soundandvision.com

 

[Rick330]

Okay then you should pay attention to what Gene said about the X3600H's amp assign feature.

"With the AVR-X3600H configured to reroute the main front L/R internal amplifiers, the preamp is physically disconnected from the power amp. This allows the preamp stage full capability of delivering up to 4Vrms unclipped when connected to external amplification as can be seen in the following output vs distortion plot courtesy of Sound United Engineering."

Read the full review here:

https://www.audioholics.com/av-receiver-reviews/denon-avr-x3600h

Another thing, don't underestimate the Marantz MM7055. Its amp is quite beefy, I would say for real world practical use it should be as powerful (if not slightly more than..) as the RMB-1555 two channel driven and slightly less under 5 channel driven conditions. You gain only 3 dB with 2X the power output so practically speaking the power output difference between the Marantz and the Rotel is completely negligible.

Take a look of the measurements in two different reviews on the 7055.

Marantz AV7005/MM7025/7055 (Test)

audiovision.de

Marantz AV7005 Surround Processor and MM7055 Amplifier HT Labs Measures

HT Labs Measures Marantz AV7005 Surround Processor Analog frequency response in Pure Direct mode: –0.05 dB at 10 Hz –0.00 dB at 20 Hz –0.01 dB at 20 kHz –0.07 dB at 50 kHz Analog frequency response with signal processing: –0.45 dB at 10 Hz –0.13 dB at 20 Hz –0.14 dB at 20 kHz

www.soundandvision.com

Thanks I actually did have the setting on my Denon I just had no idea it benefitted me lol. Everyone is so nice here spending their own time helping others.

I'll give the 6ohm 7055 a shot at powering my front 3 when my Martin Logan's get here and trust that you said it's really good.

 

[PENG]

Thanks I actually did have the setting on my Denon I just had no idea it benefitted me lol. Everyone is so nice here spending their own time helping others.

I'll give the 6ohm 7055 a shot at powering my front 3 when my Martin Logan's get here and trust that you said it's really good.

Thanks should go to @gene always watched out for the potential pre out voltage limits in his reviews/measurements. The specific issues due to the lack of the so called "preamp" mode found only in the flag ship Denon AVRs is something new that he recently highlighted and explained.

I own a MM8003 that has basically the same power amp section as your MM7055, just a larger power supply and I am also familiar with the 7055. The MM7055 should have no issues driving 8 ohm nominal speakers that have dips below 4 ohms at some frequencies; and I won't hesitate to use one to drive most 4 ohm nominal speakers in a small to medium size room sitting within say 2-4 meters with volume below "0". The Denon, and Rotels have build in fans, but I would still put an external fan on top for longevity reason. The build in fans are often there to protect the unit from failing during the warranty period, that's just my opinion though..

Lastly, in your other thread you were questioning about the Rotel's 4 ohm rating. The fact is, the RMB-1555 specifications simply stated speaker impedance "4 ohms minimum", but the 120 W rating is for 8 ohms load, there isn't any rating specified for 4 ohms load as such.

 

[Rick330]

That's good I wont overthink it. The Martin Logan's that I'm getting measured barely under 5ohm at some points anyway. Ok thanks for the advice. I'll never understand the pre out thing but at least I have the Denon speaker setting as Gene recommended and I'll pre out the center speaker and all done. Thanks again.

 

[PENG]

I'll never understand the pre out thing

Now you got me curious. I can try a point by point approach if I know which part you don't understand.

 

[Rick330]

My thought is what is the benefit of freeing the pre out so it gives the full 4volts to the amp if the amp only needs 2?

 

[snakeeyes]

Most external amps have 29dB voltage gain. Are there any higher than that?

 

[Rick330]

Mine is 29. The Rotel I was looking at was 26 which I understand needs a little more voltage and some yamahas don't put out enough. The denons put out plenty already that's why I didn't understand why the new setting in the x3600 which sends all 4 mattered.

 

[snakeeyes]

Good question. I’m still learning a bit too. Every time Peng explains it, I think I know but then comes another detail I missed originally. LOL

 

[PENG]

Will try again when I get home..

 

[KEW]

Good question. I’m still learning a bit too. Every time Peng explains it, I think I know but then comes another detail I missed originally. LOL

I once had a professor who explained learning as putting back the layers of skin on an onion!
His point was if you don't have the skin that belongs under the one that you just received in place, the new skin will just slide off the onion.
IOW, as your knowledge base builds you have better ability to have a place to put the next information you receive.
So, each time you hear a full explanation, the skin layers you have a place for stick, and the next time you receive the same information you will be ready for the next layers.
Of course, if you don't pay attention, it all slides off!

 

[AcuDefTechGuy]

Most external amps have 29dB voltage gain. Are there any higher than that?

Oh yeah for sure. I've seen 32dB and 34dB gains.

The ATI AT2000 and AT3000 amps have a gain of 34dB with the RCA connectors and 28dB with the XLR connectors.

And these amps are dead silent with both RCA and XLR.

 

[PENG]

The denons put out plenty already that's why I didn't understand why the new setting in the x3600 which sends all 4 mattered.

You are right, the X3600H has "plenty" and you don't need 4 V either in most cases.

In fact, the preamp voltage you need depends on:

1. The voltage gain of the power amp, the higher that is, the lower you can get away with.
2. The target power amp output voltage.
3. The source media content, and how loud you listen. As example, if you listen to avg 75 dB spl from 2 meter, you probably only need 0.1 Volt.

The following formulae can be used to calculate voltage gain:

Voltage gain in dB = 20 X log Vout/Vin
Voltage gain in multiplier = Vout/Vin = 10^(Voltage gain in dB/20)

Using the above formula, if the preamp output = 1.1 V and Voltage gain = 29 dB:
Power amp output voltage = Input voltage (preamp output) X 10^Voltaga gain in dB/20) = 1.1 X 10^(29/20) = 1.1 X 28.184 V = 31 V

Since Power = V^2/Z, for a resistance load of 8 ohms, Power amp output = 31^2/8 = 121.14 W

So if you have a power amp such as the RMB-1555, you only 1.1 V preamp output voltage to drive it to its rated output of 120 V.

Now if your target power amp output is 400 W, then using the above formulae, the preamp output voltage would need to be 2 V.

So again, the preamp section is not the issue. It is the internal power amp section that is potentially an issue, because as soon as the preamp output reaches about 1.2 V (that correspond to about 143 W into 8 ohms) and above, the merely 105 W rated internal power amp section may clip under certain load conditions (such as the frequency sweep that Gene applied for his bench test, using continuous sine waves),the protective circuit may act a little too aggressively and shut the unit down.

It is a case of not that you have to do something about it, but if you could, why not?