Doc modding Marantz imperial 7

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Well, not many comments when I asked for them. Expect non from me on your threads. You selfish bastards.
DIY inspired by Richard "The Doc" Dunn RIP

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Re: Doc modding Marantz imperial 7

Unread post by antonio66 »

Calm down, calm down, maybe some regular members have not yet read up Stu, must say I like it especially as you've gone for the flat base version. Great job cutting the sphere, that doesn't do itself. I only read the bits I can understand, which isn't much, that's how I'm able to keep up with this thread :lol:
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karatestu (Sat Nov 06, 2021 9:27 am)

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Re: Doc modding Marantz imperial 7

Unread post by r3xj0hn570n »

You had a plasma cutter! Sheesh.

Beware of making the speakers too short. I always thought short speakers sounded worse.

Frog legs i think. Paint them green. :P

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Re: Doc modding Marantz imperial 7

Unread post by Geoff.R.G »

Looks interesting Stu, well done. Having been up early yesterday we went to bed early and I have only just seen your latest post so I couldn’t have posted earlier.

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Sorry for the emotional explosion yesterday. It was the anniversary of my father's death and even though it was nine years ago I am a wreck every bonfire night. I miss you dad.

Anyway, thanks for the comments. I'm not needy...... honest :liar: I have A LOT of blood sweat and tears wrapped up in this little project. Average is not good enough. PityI wasted so much time chasing the impossible and ended up with a simple two way. Doc wasn't thick, KISS applies. Me being the stupid one. Stu pid :lol:

Dave, your opinion counts more than most. I went with your favourite as I trust your no nonsense, no agenda views.

Rex, I forgot about the plasma cutter. Being a part time farmer (amongst other things) has it's plus points. Shed loads of space to make a mess and store crap, materials and tools. There is stuff knocking about here that belonged to my great grand parents. There is a saying "good enough for farming" :grin: Delicate accuracy is not something we are accustomed to. He who has the biggest tractor or biggest hammer is the winner.

I'm good at throwing crappy prototypes together in a flash. But when it comes to precision and aesthetics I have to stop and think so I make a good job that my OCD won't make me throw it away in a tantrum.

This speaker is nearly done, all the details are in my head. It will be my forever speaker.......until I build the 3 way with 12" bass driver :lol:
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antonio66 (Mon Nov 08, 2021 1:54 am)
DIY inspired by Richard "The Doc" Dunn RIP

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

r3xj0hn570n wrote: Sat Nov 06, 2021 5:49 am You had a plasma cutter! Sheesh.

Beware of making the speakers too short. I always thought short speakers sounded worse.

Frog legs i think. Paint them green. :P
Cheers Rex.

I have played with height a bit. On the floor was the worst. I think I have it about right for boundary reinforcement and imaging etc. Having a tweeter that is adjustable is a valuable thing to have.

Green is my favourite colour by the way, John Deere green ofc :grin: I have loads of John deere green paint.
DIY inspired by Richard "The Doc" Dunn RIP

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Re: Doc modding Marantz imperial 7

Unread post by Grumpytim »

karatestu wrote: Fri Nov 05, 2021 6:06 pm The beauty of it all Tim, is that it almost made itself so far :grin: Cut two holes in 3mm steel this shape is tough but that is all I have had to do so far. There will be some routing to do for the driver mounting rings. And the leg and base will need making as well as the final tweeter sphere - might do that in steel anorl but haven't decided yet.

Also the way i am going to support the tweeter sphere above the mid bass is not really decided on yet but it will probably be three little legs like i use now with the cubes. I will try and isolate the tweeter cube from vibration coming from the mid bass cube if i can. Wiring and binding posts to do. Internal stuffing to finalise - fibre glass but just the right amount.

Oh and lets nots not forget the finish of the two spheres. i will have to dust off my spray gun that goes on the compressor which i haven't used for five years or more . I said this almost makes itself as there are no joints to make as such but that list of things to do is quite long :shock:
Well I like the simplicity of the 'design' you've landed on. Visually it has nods in the direction of the 1960's and the Jetsons. Plus with all the testing you've put into this endeavour it should also sound pretty good.

In short I have nothing but admiration for what you have tried to acheive, whilst a lot of the science stuff goes way,way over my head I have learned s few things from this thread.
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karatestu (Sat Nov 06, 2021 11:35 am)

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Re: Doc modding Marantz imperial 7

Unread post by Latteman »

Dark red is my fav
Prefer a matt or silk finish- not glossy
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karatestu (Sat Nov 06, 2021 11:36 am) • antonio66 (Mon Nov 08, 2021 1:57 am)
Analogue Source -
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Latteman wrote: Sat Nov 06, 2021 10:51 am Dark red is my fav
Prefer a matt or silk finish- not glossy
Yes I agree, a matt or silk finish is preferable for me too (and my wife)

Dark red is an option as well as black ofc and cream. Unfortunately John deere green will stick out a bit. White, yellow, orange need not apply.

I thought I might have to spray the b&w mid bass with plastidip the same colour as the 2" tweeter :think:
DIY inspired by Richard "The Doc" Dunn RIP

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Grumpytim wrote: Sat Nov 06, 2021 10:50 am
karatestu wrote: Fri Nov 05, 2021 6:06 pm The beauty of it all Tim, is that it almost made itself so far :grin: Cut two holes in 3mm steel this shape is tough but that is all I have had to do so far. There will be some routing to do for the driver mounting rings. And the leg and base will need making as well as the final tweeter sphere - might do that in steel anorl but haven't decided yet.

Also the way i am going to support the tweeter sphere above the mid bass is not really decided on yet but it will probably be three little legs like i use now with the cubes. I will try and isolate the tweeter cube from vibration coming from the mid bass cube if i can. Wiring and binding posts to do. Internal stuffing to finalise - fibre glass but just the right amount.

Oh and lets nots not forget the finish of the two spheres. i will have to dust off my spray gun that goes on the compressor which i haven't used for five years or more . I said this almost makes itself as there are no joints to make as such but that list of things to do is quite long :shock:
Well I like the simplicity of the 'design' you've landed on. Visually it has nods in the direction of the 1960's and the Jetsons. Plus with all the testing you've put into this endeavour it should also sound pretty good.

In short I have nothing but admiration for what you have tried to acheive, whilst a lot of the science stuff goes way,way over my head I have learned s few things from this thread.
Thanks Tim. Glad you have learned a few things from my ramblings I try to spell things out in layman's terms if I can because I remember being confused by the jargon that crops up when you read about such things on the Internet.

I seem to be obsessed now with curves, spheres and symmetry. It is elegantly simple I think. The design has ended up looking really good imo but the aesthetics were always second to how it sounds. It is only now that I am thinking about the fine cosmetic detail.
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Grumpytim (Sat Nov 06, 2021 12:59 pm)
DIY inspired by Richard "The Doc" Dunn RIP

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