Doc modding Marantz imperial 7

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Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Wed Oct 09, 2019 4:20 pm

They won't cover the same frequencies. The mid range won't do high frequencies.

Fuckin up the sound in my experience comes when you split the frequency spectrum.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Oct 09, 2019 5:52 pm

All that would change is doubling the number of mid drivers and doubling the volume of the mid enclosure so the spl of the mid is increased to the same level as the tweeter. Then remove the tweeter padding resistor because it is no longer needed.

The 6dB increase only happens at lower frequencies apparently so i am not sure it would work anyway. And the mid driver amp has to work harder. And two more drivers are much more expensive than two resistors.
DIY inspired by Richard "The Doc" Dunn RIP

Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Wed Oct 09, 2019 5:53 pm

Why wouldn't the resistor be needed?

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Oct 09, 2019 6:00 pm

Beacause when you put two identical drivers in parallel instead of using one you gain an extra 6dB in total output. That 6 dB added to the mid drivers 84dB sensitivity equals 90 dB which is the same as tbe tweeter. So no padding needed (in theory).
DIY inspired by Richard "The Doc" Dunn RIP

Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Wed Oct 09, 2019 6:08 pm

Ah I see. I reckon that's theory. But as we no the proof of the pudding is in the eating. Good luck.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Oct 09, 2019 6:44 pm

I am not sure i will even try it. More expense when i said a few weeks ago that i was going to just use the parts i already have :roll:
DIY inspired by Richard "The Doc" Dunn RIP

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Thu Oct 10, 2019 3:42 pm

I know reviews are frowned upon here (and i agree) but here is a review of a floor standing semi omni speaker i had not come across before.

SEE HERE
DIY inspired by Richard "The Doc" Dunn RIP

Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Thu Oct 10, 2019 7:37 pm

It's from 6moons, financial or product inducements are essential.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Thu Oct 10, 2019 8:01 pm

Daniel Quinn wrote:
Thu Oct 10, 2019 7:37 pm
It's from 6moons, financial or product inducements are essential.
I agree. However, it is semi omni and you don't see so many of them. I was not advocating that anyone should actually believe what was written :naughty:
DIY inspired by Richard "The Doc" Dunn RIP

antonio66
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Re: Doc modding Marantz imperial 7

Unread post by antonio66 » Fri Oct 11, 2019 5:58 am

Never heard of them either Stu, thanks for the link.

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