Doc modding Marantz imperial 7

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karatestu
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Doc modding Marantz imperial 7

Unread post by karatestu »

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
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antonio66
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Re: Doc modding Marantz imperial 7

Unread post by antonio66 »

Good luck with this project, looking forward to see how you get on.

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew »

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.

George Hincapie
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Re: Doc modding Marantz imperial 7

Unread post by George Hincapie »

Marantz! <3

Good luck with it all.

Daniel Quinn
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn »

Can you just not make them two way ?

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew »

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

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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn »

I see .

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

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
DIY FREE ZONE

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew »

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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Re: Doc modding Marantz imperial 7

Unread post by CycleCoach »

Good luck with the mods - I for one will be watching with interest! :epop:
I think I might be in the HiFi trade.
I am not currently seeking treatment for this.
Current System: Linn LP12 Lingo Ekos Troika, NVA PHONO2 with BBPSU, NVA AP20 (White), Quad ESL 57s &/or NVA Cube3s (White)

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