Doc modding Marantz imperial 7

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karatestu
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Doc modding Marantz imperial 7

Unread post by karatestu » Tue Feb 07, 2017 7:44 am

Picked a pair of these up for £27. SEE HERE .

They are mid 70's 3 way, made in the US of A. Walnut cabs, 12 " bass, 3 1/2 2" mid, 1 3/4 " tweeter and a bloody front port. All drivers foam surrounds are shagged.

Plans for these are
  • throw everything away except the wooden cabs
    steel plate
    insert doc modded 12" bass and visaton G25 tweeter
    3.3uf series cap and padding resistor for tweeter
    renovate cab exterior
    block port
The problem i have is all the drivers are shagged so i wont be able to use the 3 1/2" mid (unless i refoam it). What i would like to know is - is there a recommended mid river for use with doc modded bass and visaton G25 tweeter ?

Visaton have some nice drivers in their range such as THIS or THIS

Not exactly the same size as the originals but i doubt that matters.

I know there will be other issues to resolve like integrating the mid and series wiring.

Stu
I love fluffy bunnies

antonio66
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Re: Doc modding Marantz imperial 7

Unread post by antonio66 » Tue Feb 07, 2017 9:37 am

Good luck with this project, looking forward to see how you get on.
My set-up: PT Too,Rega 250 AO mods, Lyra Helikon, NVA Phono 2 + Extra PS, Project CD Transport/Project LPSU, Calyx 192 dac, NVA P50, NVA A60, Cube 3's. Headphones Senn HD700s and NVA AP10H. SSP/SC interconnect and NVA LS5 speaker cable.

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Tue Feb 07, 2017 10:27 am

Use the Doc Mod 5 inch for mid driver, you may find you can use the port hole. Or block that and open up the mid hole.

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George Hincapie
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Re: Doc modding Marantz imperial 7

Unread post by George Hincapie » Tue Feb 07, 2017 10:39 am

Marantz! <3

Good luck with it all.
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Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Tue Feb 07, 2017 10:57 am

Can you just not make them two way ?
Even a stroke didn't result in me liking AOS

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Tue Feb 07, 2017 11:01 am

Not with a 12 inch you can't. With a 12 inch you need a mid driver.

Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn » Tue Feb 07, 2017 11:01 am

I see .
Even a stroke didn't result in me liking AOS

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Tue Feb 07, 2017 11:36 am

Thanks for the replies.

Cheers Doc, your 5" drivers it is then :grin:

This is my shopping list then;

Doc modded 12" bass drivers (2 of)
Doc modded 5" drivers (2 of)
Visaton G25 FFL tweeters (2 of)
Caps and resistors (not sure what I will need yet)
3mm steel plate (doubled up to make 6mm)
Bison kit for sticking steel in and drivers possibly
12 pack of Guinness.

I usually hardwire speaker cables directly to the drivers with my Avondale blacklink cables. Will have to make sure the holes for this are air tight. I also use my xovers right behind the amps. Will try this again but will also compare with putting caps and resistors just before the drivers.

I am very excited - need a cumming in my pants emoticon :shock:

Stu
I love fluffy bunnies

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Tue Feb 07, 2017 12:14 pm

Visaton you buy from others not me. Paypal gift me £250 for Doc Mod drivers and £10 postage so £260.00 when you are ready. 51/2inchers ready, but I will have to order and dope 12 inchers.

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CycleCoach
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Re: Doc modding Marantz imperial 7

Unread post by CycleCoach » Tue Feb 07, 2017 1:30 pm

Good luck with the mods - I for one will be watching with interest! :epop:
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