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Question about Bi Amping

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Robert D

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Bear with me because im inexperienced, I have never bi amped before, but wondering about trying it now. Ive got a pair of Prodigies. Right now i am powering them with an Aragon 8008 fed off a pre-out from my Marantz SR8012.



I'm wondering if I could use the L and R channels of the Marantz receiver to power the woofers and then the Aragon just for the panels. Wondering if the receiver's left and right channels would even send out a signal when the pre-outs for those channels are being used.

From what I understand, you want to use the same amp for both when you do this, or at least make sure that the voltage gain is the same on both. I see the Aragon has 28 db. Not sure what the Marantz 8012 is but thinking its lower. When calibrating it with Audyssey, it wouldn't be able to balance the two amps on the front speakers? Its not capable of setting the gain different for each is it?

The Aragon seems to do a good job powering the speakers now but I'm wondering if i could make them sound better doing this. My guess is no, especially since the gain is different on both amps. Not able to test it now since my panels are out for service. Id need to pick up another set of speaker cables too.

Right now the left and right main channels of the Marantz receiver's amp aren't being used.
 

Spike

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Assuming that the Marantz send out speaker level signals to drive the woofer, I think you will get worse sound quality than going with the Aragon driving full range. The reason being the Aragon is a much better amplifier than the Marantz's amplifier section. The Aragon 8008 is a very capable amplifier. What is it lacking with the Aragon that you're trying to address?
 

Robert D

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Assuming that the Marantz send out speaker level signals to drive the woofer, I think you will get worse sound quality than going with the Aragon driving full range. The reason being the Aragon is a much better amplifier than the Marantz's amplifier section. The Aragon 8008 is a very capable amplifier. What is it lacking with the Aragon that you're trying to address?
Just that the base on the Prodigies seems to be lacking. Someone on here suggested that maybe I didnt have the sub properly in phase with them. When I get it all up an running again I will have to play around with it a lot more. I found that by setting the crossover on the Prodigies at 80 HZ rather than 40 where Audyssey had, that the base sounded better. I think the sub was set to cut off at around 80 or 100 HZ. Youd think there would be more base with the Prodigies cut off at a lower frequency, since their range is supposed to go down to 28HZ. Prodigy

The other member suggested that the phase of the speakers and sub were acting against each other perhaps at the lower freq.
 

Spike

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The Prodigy can go deeper than my ReQuest. I am running my ReQuests without subs and don't feel that I am missing any bass. I would try your Prodigies without the subs first to understand their limits before integrating with the subs. I am suspecting phase cancellation between the subs and Prodigy is the culprit here.
 

Robert D

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The Prodigy can go deeper than my ReQuest. I am running my ReQuests without subs and don't feel that I am missing any bass. I would try your Prodigies without the subs first to understand their limits before integrating with the subs. I am suspecting phase cancellation between the subs and Prodigy is the culprit here.
That would certainly make a lot of sense. Its hard to believe that it could be that dramatic. What I will do is just play the prodigies in stereo without the sub and without Audyssey. See how that sounds for base.

I think I already did that and the base was lacking, but cant remember for sure.
 

twich54

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Robert , it's 'bass' not base ..... ;)

good luck with getting your 'bass' sorted out !
 

RAH

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Bear with me because im inexperienced, I have never bi amped before, but wondering about trying it now. Ive got a pair of Prodigies. Right now i am powering them with an Aragon 8008 fed off a pre-out from my Marantz SR8012.



I'm wondering if I could use the L and R channels of the Marantz receiver to power the woofers and then the Aragon just for the panels. Wondering if the receiver's left and right channels would even send out a signal when the pre-outs for those channels are being used.

From what I understand, you want to use the same amp for both when you do this, or at least make sure that the voltage gain is the same on both. I see the Aragon has 28 db. Not sure what the Marantz 8012 is but thinking its lower. When calibrating it with Audyssey, it wouldn't be able to balance the two amps on the front speakers? Its not capable of setting the gain different for each is it?

The Aragon seems to do a good job powering the speakers now but I'm wondering if i could make them sound better doing this. My guess is no, especially since the gain is different on both amps. Not able to test it now since my panels are out for service. Id need to pick up another set of speaker cables too.

Right now the left and right main channels of the Marantz receiver's amp aren't being used.
Denon and Marantz are sister companies. I have a Denon integrated. Previously Denon preout was taken to Anthem power in. Both amps have same 29db gain. I have attached two pair of speakers, one to Denon and the other one to Anthem. To answer your question sound is produced by both. Therefore Marantz may also be able to drive woofers when preout is taken to power amp to drive ELS.

Do not wonder rather try. Does not hurt to try once your Prodigy’s are repaired. You can always borrow a loudspeaker cable to try useful for biamping. My guess is Aragon will make the now refurbished panel sound great. I guess Marantz will do a decent job of driving the woofers.

How woofer and ELS will sound together when biamped? My guess may sound best so far. However, I do not know.

You can try and please let us know the result of your small experiment.
 

Robert D

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Denon and Marantz are sister companies. I have a Denon integrated. Previously Denon preout was taken to Anthem power in. Both amps have same 29db gain. I have attached two pair of speakers, one to Denon and the other one to Anthem. To answer your question sound is produced by both. Therefore Marantz may also be able to drive woofers when preout is taken to power amp to drive ELS.

Do not wonder rather try. Does not hurt to try once your Prodigy’s are repaired. You can always borrow a loudspeaker cable to try useful for biamping. My guess is Aragon will make the now refurbished panel sound great. I guess Marantz will do a decent job of driving the woofers.

How woofer and ELS will sound together when biamped? My guess may sound best so far. However, I do not know.

You can try and please let us know the result of your small experiment.
Ok, I will try it out. I was thinking of trying. The amp in the Marantz powers my center channel theater i just fine, so maybe it will work since its just powering a woofer.
 

Robert D

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Will I need to run Audyssey again when I switch to biamping the speakers? I'd think probably not, it wouldnt have much effect? I could also just test it with Audyssey turned off.
 

RAH

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Will I need to run Audyssey again when I switch to biamping the speakers? I'd think probably not, it wouldnt have much effect? I could also just test it with Audyssey turned off.
First terrible name of room correction software. Sometimes marketers go to far. I feel embarrassed to even use this word. You will know once you get back your ML’s.

I biamp my 9’s. Anthem STR integrated amp drives ELS. Anthem power amp drives woofers. I have kept the more refined of the two for ELS duty. My STR tone controls and gain controls are at flat position. All I need to adjust is the volume. I use no room correction software or ARC. Since marantz and Aragon have different voltage gain you may want to set the volume separately for woofer and ELS.

For you I really hope that panel repair workers do excellent work and your panels are just as great sonically as new panels.
 

Robert D

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First terrible name of room correction software. Sometimes marketers go to far. I feel embarrassed to even use this word. You will know once you get back your ML’s.

I biamp my 9’s. Anthem STR integrated amp drives ELS. Anthem power amp drives woofers. I have kept the more refined of the two for ELS duty. My STR tone controls and gain controls are at flat position. All I need to adjust is the volume. I use no room correction software or ARC. Since marantz and Aragon have different voltage gain you may want to set the volume separately for woofer and ELS.

For you I really hope that panel repair workers do excellent work and your panels are just as great sonically as new panels.
Russ assured me that they should sound like new, especially the volume level. Now the volume isn't great and it seems high frequencies are missing. The Audyssey seemed to boost the high frequencies and it sounded good, but I had to crank the gain way up on the receiver to get proper volume, in fact it was maxed out.

He talked like the biggest difference will be volume level, but i expect high frequency improvement too. He tests the panels before and after he works on them. He even said that if he thinks the panels are ok he will tell me they don't need work.

How would I adjust the volume of the 2 amps independent of each other? There is no volume or gain knob on the aragon. Maybe its a software setting im not aware of. I think there might be a phone app, never used anything.
 

JonFo

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... How would I adjust the volume of the 2 amps independent of each other? There is no volume or gain knob on the aragon. Maybe its a software setting im not aware of. I think there might be a phone app, never used anything.
That's the thing when bi-amping, you need a way to adjust the gain to each amp (unless using 2 identical amps). So I'd not even try it until you are able to address that.
Maybe, just maybe, Audyssey would be able to compensate with more or less EQ on the range that needed it, but it might not deliver a good result.

BTW- do set the L/R to 'Small' and the crossover at 80Hz. Those old woofers are likely not able to deliver. Plus, as you experienced, subs are designed for that range and likely better positioned.

I run active crossovers and amps for each driver in my rig, and I use 80Hz crossover points in the preamp.
 

Robert D

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That's the thing when bi-amping, you need a way to adjust the gain to each amp (unless using 2 identical amps). So I'd not even try it until you are able to address that.
Maybe, just maybe, Audyssey would be able to compensate with more or less EQ on the range that needed it, but it might not deliver a good result.

BTW- do set the L/R to 'Small' and the crossover at 80Hz. Those old woofers are likely not able to deliver. Plus, as you experienced, subs are designed for that range and likely better positioned.

I run active crossovers and amps for each driver in my rig, and I use 80Hz crossover points in the preamp.
Ill eventually set it up with Audyssey again. Last time it set the crossover at around 40 HZ on its own, and then I put it back up to 80 and the system sounded better. I think I had them set to large, but had the sub getting the LFE signal from all of the channels, including the front L and R. So I should have been getting some overlap in the lower frequencies down to about 40 HZ in the Prodigies, but it didnt seem like it because when I turned the crossover up to 80 HZ it sounded like the bass was stronger. I didnt even change the crossover point for the sub. So that results was a surprise. I figured the bass would be stronger since both the sub and the prodigies would be playing those low frequencies. Maybe like our other member said, the two were out of phase and canceling out each other?

Probably have to mess with the phase on the sub to see if I can make it sound better.
 

Spike

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How would I adjust the volume of the 2 amps independent of each other?
In my case where I am bi-amping with a 50-watt tube amp on the panel, and 100-watter on the bass, I had to look at the gain factor for both amps. 23db gain for the tube amp, and 26.8 for the Levinson ML331. In this case, I need to reduce the gain at the woofers by 3db. I am currently using a fixed 3db in-line attenuator from Harrison Labs and they work well. The in-line attenuators go between the pre-amp and the solid-state amp to bring the gain down to the same level as the tube amps. Here's a drawing of my system to give you an idea

1597963984906.png


The Harrison Labs attenuators can be found here at Parts Express:
Harrison Labs 3db in-line attenuator
 

Robert D

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In my case where I am bi-amping with a 50-watt tube amp on the panel, and 100-watter on the bass, I had to look at the gain factor for both amps. 23db gain for the tube amp, and 26.8 for the Levinson ML331. In this case, I need to reduce the gain at the woofers by 3db. I am currently using a fixed 3db in-line attenuator from Harrison Labs and they work well. The in-line attenuators go between the pre-amp and the solid-state amp to bring the gain down to the same level as the tube amps. Here's a drawing of my system to give you an idea

View attachment 20854

The Harrison Labs attenuators can be found here at Parts Express:
Harrison Labs 3db in-line attenuator
Wow, thanks. My only problem then would be figuring out what the gain is on the Marantz receiver I linked on this thread.SR8012. I guess the aragon amp has a higher gain, but how much? Marantz doesn't seem to list the gain anywhere, I guess because it is a receiver? People probably never bi amp using them.
 

Spike

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Comparing specs between the Aragon vs Marantz for the specific item of producing 1W (2.8V output), we have the following calculated gain factors:

AmplifierInput sensitivity for 2.8V outputGain factor
Aragon120 mV27.44 db
Marantz200 mV23.01 db

Base on the above mentioned figures, the Marantz is about 4db lower than the Aragon. But that is NOT the whole story. While the Aragon clearly specifies 400W into 4ohm, the Marantz's spec is a bit questionable, mentioning 6ohm (instead of 4ohm) load AND a narrow 1kHz signal (instead of full-range 20Hz - 20kHz)
140 W + 140 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)
175 W + 175 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)


The Marantz may produce sound on your woofers, but it is clearly not in the same league as the Aragon. Will the Marantz have enough control on the woofers to keep up with the Aragon? I am not sure bi-amping with the Marantz + Aragon combination will yield better result than going full-range with the Aragon by itself.
 

Robert D

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Comparing specs between the Aragon vs Marantz for the specific item of producing 1W (2.8V output), we have the following calculated gain factors:

AmplifierInput sensitivity for 2.8V outputGain factor
Aragon120 mV27.44 db
Marantz200 mV23.01 db

Base on the above mentioned figures, the Marantz is about 4db lower than the Aragon. But that is NOT the whole story. While the Aragon clearly specifies 400W into 4ohm, the Marantz's spec is a bit questionable, mentioning 6ohm (instead of 4ohm) load AND a narrow 1kHz signal (instead of full-range 20Hz - 20kHz)
140 W + 140 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.05 % T.H.D.)
175 W + 175 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)


The Marantz may produce sound on your woofers, but it is clearly not in the same league as the Aragon. Will the Marantz have enough control on the woofers to keep up with the Aragon? I am not sure bi-amping with the Marantz + Aragon combination will yield better result than going full-range with the Aragon by itself.
Im leaning toward thinking that myself. thanks for figuring out the gain on the Marantz. I messed around with some numbers and think I calculated the same but wasnt confident in my finding. Logically it doesnt make a lot of sense in supressing the aragon down 4 db.
 

Robert D

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