Integra DRX 3.4 vs Denon 3700H Preamp Output

[Decibals]

I am considering a purchase of either the new Integra DRX 3.4 or Denon avr 3700H but I plan to use the preamp output to connect to a 3 channel amp that requires 2V to reach full rated power. I am leaning toward the Integra as I like Dirac room correction but what concerns me is the pre amp output voltage of 1V versus the Denon that has amplifier disconnect and can run maximum 4V unclipped from the preamp. Attached is what I see as specs for the Integra DRX 3.4. Any thoughts? I called Integra support and the representative said he spoke to his engineer and 1V is max for their pre-out but that does not sound correct to me.

 

[lovinthehd]

Phone support....meh. I also doubt the Onkyo is limited to 1V, that's just a nominal rating I'd think (or rather useless as a pre-out)....but they have gone thru some changes there. My old Onkyo (HT-R370) does show 200mv and a max of 4.6V in the manual fwiw. You already have the external amp?

ps Will you be using the avr's amps otherwise or is it only a 3.1 setup?

 

[Decibals]

Yes, I have had the external amp for awhile. I have a 3.1 setup with no plans to use other amp channels in the near term. If I do, I would get an additional multi channel amp.

 

[lovinthehd]

Seems the 3700 in preamp mode might be your better "bet" unless you can get better info from Onkyo

 

[Decibals]

Thanks for your advice

 

[lovinthehd]

Just what amp is it?

 

[Decibals]

Emotiva XPA DR3

 

[lovinthehd]

Impressive amp but doubtful there's a lot of difference in terms of audibility at usual listening levels....but hard to know what your situation is from what you mention....might not make any difference as to which preamp. Do you have 20A circuit for that setup? Ever need that sort of juice really?

ps FWIW am running slightly more powerful amps than that right now but don't need to....

 

[Decibals]

No dedicated 20amp dedicated circuit yet. I have it connected to the pre outs on an older Sony 2400ES receiver and have noticed greater headroom and dynamic envelope.

 

[lovinthehd]

have noticed greater headroom and dynamic envelope.

How do you determine that?

 

[Decibals]

Just by listening to favorite films we know very well with Sony alone and with the external amp...not a blind test by any means and not expectation bias. Our ears could hear a difference.

 

[lovinthehd]

Just by listening to favorite films we know very well with Sony alone and with the external amp...not a blind test by any means and not expectation bias. Our ears could hear a difference.

Uh, what Sony? Speakers are?

 

[Decibals]

We noticed not so much with sound effects but with the score to films such as Lord of the Rings, Prometheus, etc. Brass and horn instruments in particular sounded better.

 

[Decibals]

Sony 2400ES powering older Definitive Technology BP20 speakers. They are bipolar speakers that have (4) 6.5in midbass drivers in a transmission line. Also, 2 aperiodic dome tweeters. This was a model before Def Tech started integrating subwoofers into their cabinets in the late nineties.

 

[dlaloum]

Word from Onkyo/Integra (who I asked the question of)- is that peak output is 2V...

So that seems a good match to your amp requirements.

ASR did a technical review of the X3700h - and in pure preamp mode it can put out 4V.... very clean too!

But when it is powering its internal amps, the maximum output drops dramatically and it clips at 1.4V...

Denon AVR-X3700H AVR Review

This is a review and detailed measurements of Denon AVR-X3700H 9.2 channel 8K Home Theater AV Receiver (AVR). It is kindly loaned to me by a local member and costs US $1,199. Visually, if you have seen one AVR, you have seen the look of the AVR-X3700H: The input selector is plastic and...

www.audiosciencereview.com

The Onkyo/Integra/Pioneer family have yet to be thoroughly tested in this way... you can never tell what flaws may get flushed out!

I have an Integra DRX 3.4 on order - and intend to use it to drive external amps for LCR... while using the internal amps for surrounds,

 

[PENG]

Word from Onkyo/Integra (who I asked the question of)- is that peak output is 2V...

So that seems a good match to your amp requirements.

ASR did a technical review of the X3700h - and in pure preamp mode it can put out 4V.... very clean too!

But when it is powering its internal amps, the maximum output drops dramatically and it clips at 1.4V...

Denon AVR-X3700H AVR Review

This is a review and detailed measurements of Denon AVR-X3700H 9.2 channel 8K Home Theater AV Receiver (AVR). It is kindly loaned to me by a local member and costs US $1,199. Visually, if you have seen one AVR, you have seen the look of the AVR-X3700H: The input selector is plastic and...

www.audiosciencereview.com

The Onkyo/Integra/Pioneer family have yet to be thoroughly tested in this way... you can never tell what flaws may get flushed out!

I have an Integra DRX 3.4 on order - and intend to use it to drive external amps for LCR... while using the internal amps for surrounds,

The 3700 preout can output much higher than 2V, likely 4 V.

The 1.4 V you mentioned is not a limit but the level when the THD+N will be at ots best.

It is like a power amp can output 100 w 8 ohms, at 0.05% thd+n but may be capable of 150 w at 1% thd+n.

In that ASR review on the 3700 you should look at the whole graph, not just Amir's ambiquous and somewhat misleading comment.

 

[PENG]

I wish Amir would edit his misleading comments but I think he would be too busy to do it even if I can convince him that there is a need. In the meantime people will continue to quote or make their own comments, advise on forum based on Amir's remark below, and it has in fact fast becoming another forum hearsay.

Denon AVR-X3700H AVR Review | Audio Science Review (ASR) Forum

As you see, peak performance with the amplifiers off is around 1.1 volts with SINAD of 101 dB which is excellent for an AVR. With the amps on, you are OK up to 1.4 volt output before it nose dives. So when selecting an external amplifier for channels beyond fronts, make sure it can output its maximum power at or below 1.4 volts (usually specified as "sensitivity").

Is he wrong, absolutely not, but if anyone would take a more detailed look (in non preamp mode)
One can see that at 2V, the drop did not "nose dive", in fact it started to level off to about 0.017%THD+N, still better than some other AVRs and integrated amps. The "nose dive" from1.4 V was true too in relative sense but it was not because the preamp clipped, it was where the power amp started to clip thereby feeding back some of the bad stuff (distortions, noise) back to the pre out.

I can continue to post clarifications I felt appropriate to Amir's but the ratio of people reading his original point and my intended clarification point would probably be higher than 100,00 to 1, if not higher.

I really much prefer Gene's clearer message, when he measured the pre out of the AVR-X3300H, his remarks were:

Denon AVR-X3300W Preamplifier Measurements

One thing I really love about Denon receivers is they NEVER skimp on their preamp out circuits. Like past models, the AVR-X3300W had an ample amount of drive. I measured a whopping 4.5Vrms unclipped output, which is more than double the voltage needed to make virtually any amplifier reach full rated power. Yamaha please pay attention and step your game up particularly with your AV receivers in this price range that clip above 1.6Vrms. A preamp output of less than 2Vrms is unacceptable in my book.

 

[mtrot]

I wish Amir would edit his misleading comments but I think he would be too busy to do it even if I can convince him that there is a need. In the meantime people will continue to quote or make their own comments, advise on forum based on Amir's remark below, and it has in fact fast becoming another forum hearsay.

Denon AVR-X3700H AVR Review | Audio Science Review (ASR) Forum


Is he wrong, absolutely not, but if anyone would take a more detailed look (in non preamp mode)
One can see that at 2V, the drop did not "nose dive", in fact it started to level off to about 0.017%THD+N, still better than some other AVRs and integrated amps. The "nose dive" from1.4 V was true too in relative sense but it was not because the preamp clipped, it was where the power amp started to clip thereby feeding back some of the bad stuff (distortions, noise) back to the pre out.

I can continue to post clarifications I felt appropriate to Amir's but the ratio of people reading his original point and my intended clarification point would probably be higher than 100,00 to 1, if not higher.

View attachment 53350

I really much prefer Gene's clearer message, when he measured the pre out of the AVR-X3300H, his remarks were:

I think Gene commented on the similar pre-amp output in his review of the AVR-X5200, my current AVR.

 

[lovinthehd]

Maybe one of you guys with the Integra can send it to Amir first . I've seen more testing of preout details on Yamaha and Denon than Onkyo.....sure would be nice especially some of the new models with Dirac....

 

[dlaloum]

Somebody did post a few days back that they were intending to send their Onkyo/Integra in to Amir for testing...