• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Denon owners of receivers with multi channel pre-outs, you'll LOVE this... if it works

Status
Not open for further replies.
OP
M

mike7877

Addicted to Fun and Learning
Joined
Aug 5, 2021
Messages
631
Likes
127
This means that Denon's pre-outs are nothing but passive galvanic access points between the preamp and power amp stages, completely unbuffered... Seems like a poor implementation... Such a suggested connection will cause overload on the connected source, as it expect a minimum of 7kOhms impedance, not few hundreds Ohms...
The actual preamp probably has an output of around 100 ohms - denon probably put a 1.2k ohm resistor after it to prevent too much current being drawn by other amps with very low input impedances. For safety reasons.

It's just the middle 7 channels that are unbuffered, I wish they all were. Higher fidelity. At least the center channel is included. Dunno if you read already,center, surround, surround back, and height 1 can all be used this way. I'm going to use them for an active crossover project :D
 
OP
M

mike7877

Addicted to Fun and Learning
Joined
Aug 5, 2021
Messages
631
Likes
127
Further to the above post. Here's the breakdown block diagram of the Toshiba IC for each "preamp out" channel.

If you are driving into the IC (as the OP is doing), the "input impedance"* of the preceding volume stage will vary according to the volume setting on the AVR. As he is likely to turn it "right down" to -∞, as I mentioned above, the OUTA will be pulled to virtual/actual GND.

The OP will achieve better performance if he winds the volume control all the way up and ironically, still feeds his inputs in via the outputs. Otherwise he has a variable high filter that is dependant on the volume control of the AVR. All in all, it is a non-ideal, non-HiFi "discovery". Especially when he changes sources at full volume and destroys his hearing, speakers and maybe the AVR. :facepalm:

View attachment 160453

* what the DAC/source "sees" as it drives into the "pre-amp outs". :)

Position of volume control has no effect on tone at all. Just more random noise. Pretty much bunks everything you just said.

I do appreciate you thinking about this with more knowledge and info than I, but you've got at least one point wrong.

I think it's where you think I have direct access to the Denon's preamp out... there's a 1.2k ohm resistor there, which wouldn't leave much power at the preamp output
 

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
I'm going to use them for an active crossover project :D
Would you not consider something along the lines of a JAB3 or JAB5 for such a project? They are very affordable (<$65) and offer a plethora of channels, with onboard DSP that you can program via Sigma Studio.
 
OP
M

mike7877

Addicted to Fun and Learning
Joined
Aug 5, 2021
Messages
631
Likes
127
Would you not consider something along the lines of a JAB3 or JAB5 for such a project? They are very affordable (<$65) and offer a plethora of channels, with onboard DSP that you can program via Sigma Studio.
Yes, eventually. For when it's a dedicated system. But for the testing and optimization of filters and driver location I'll use my 3700
 

Chrispy

Master Contributor
Forum Donor
Joined
Feb 7, 2020
Messages
7,751
Likes
5,910
Location
PNW
Knowing that you can very easily configure it to sound even better than it does already, doesn't appeal to you?
Then this thread's not for you! And I'm not sure why you decided to comment...

You - "I like it already, the free sport package is of NO interest to me. It makes the car no faster"

Me - "Sport package makes the car faster when you drive it right, having great tires too helps of course...
So you don't know how to drive and you buy used tires (not that there's anything wrong with used speakers) and drive like a grandma

(our conversation from your post, pointless)

When your current 3600 doesn't perfectly match the capability of your speakers which also perfectly match your ears anymore, and you want your 3600 to sound better, come back to this thread and read which two cables to switch around to do so!
Is it "better" or simply "different"? How did you measure the difference?
 

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
Yes, eventually. For when it's a dedicated system. But for the testing and optimization of filters and driver location I'll use my 3700
I am unsure how familiar you are crossover implementation but if using an AVR, it is imperative (even more so than usual) that you place failsafe capacitors on the tweeters. Otherwise, it would take only one small mistake with the AVR's own volume control to destroy them.
 
OP
M

mike7877

Addicted to Fun and Learning
Joined
Aug 5, 2021
Messages
631
Likes
127
Is it "better" or simply "different"? How did you measure the difference?

It is clearer, and the sound image is wider. By clearer I mean sounds in songs that were previously unidentifiable became obvious. And repeating sounds in songs which I previously thought were all at the same level, are actually slightly different each time.
 
OP
M

mike7877

Addicted to Fun and Learning
Joined
Aug 5, 2021
Messages
631
Likes
127
I am unsure how familiar you are crossover implementation but if using an AVR, it is imperative (even more so than usual) that you place failsafe capacitors on the tweeters. Otherwise, it would take only one small mistake with the AVR's own volume control to destroy them.

I plan to, the tweeters are ATC's S-spec tweeters. They're not sold individually, so I'd have to buy the cheapest pair which includes them, which is like 6k Canadian. Maybe they'd fix it under warranty if I said it blew up in its included enclosure. Matched pairs are ideal (these are, to 0.5db). So the warranty way isn't good, I'd have an unmatched set. I plan to use them to about 1.7khz (3rd order butterworth) so important that Fs is close (ATC s-spec tweeters have a 925hz resonance, high enough that for my crossover point they should be matched. I'd like resonance to be a bit lower, but the dual suspension design is to die for. I broke them in with an 11hz sine wave. Never seen tweeters move in such a way, it was surreal. And silent!
 
Last edited:

VintageFlanker

Major Contributor
Forum Donor
Joined
Sep 20, 2018
Messages
4,940
Likes
19,692
Location
Paris
bored-icegif-1.gif
 

Chrispy

Master Contributor
Forum Donor
Joined
Feb 7, 2020
Messages
7,751
Likes
5,910
Location
PNW
It is clearer, and the sound image is wider. By clearer I mean sounds in songs that were previously unidentifiable became obvious. And repeating sounds in songs which I previously thought were all at the same level, are actually slightly different each time.
Why would the soundstage change? Sounds like you don't really know what you're experiencing. Could simply be level differences but since you're not doing any actual direct comparison, placebo no doubt has an influence as well.
 

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
It is almost certainly expectation bias. Not only is this a sighted comparison but it is not level matched and rapid switching is not possible. I would be more surprised if he claimed to hear no difference at all.
 

beren777

Senior Member
Joined
Feb 25, 2020
Messages
339
Likes
589
This can all be easily validated by OP sending his 3700 to Amir for measurements along with a liability waiver. Amir can pump signal into the preouts and see how the amps measure compared to CD input without digitization. If this is a newer build 3700H, many of us have wanted to see how the new DAC measures anyway and Amir can check that at the same time.
 

Spkrdctr

Major Contributor
Joined
Apr 22, 2021
Messages
2,212
Likes
2,934
Ok, I just wanted to say that after reading this thread I just beat my head against the wall and now my forehead hurts! I see so much fooling around (tweaks) with people trying to get better sound with no testing. Just a minute I will be right back.

There I just beat my head against the wall some more. I just cant understand or take this silly nonsense. To the OP I'm sure you hear better sound in a sighted non-prepared test. But as Pres Biden would say "Come on man!" This is just the typical uncontrolled bias from the brain at work. But, at least you had fun doing it. I on the other hand have a killer pain near my forehead. :) I will just walk away now before I have to go to the clinic.?
 
Status
Not open for further replies.
Top Bottom