Search found 5538 matches

by karatestu
Thu Jul 01, 2021 8:27 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

I have made four holes in another 150mm diameter indestructible dog ball :grin: Blue this time. Done with a hole saw, tape measure and a few metal squares. I am very pleased with it so far, the holes are in exactly the right places and 90 deg between each hole and it's neighbours. Just needs a bit o...
by karatestu
Wed Jun 30, 2021 12:38 pm
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Tweeter protectors for when little fingers are around :grin: https://www.avsforum.com/attachments/dynaudio-protection-tweeter-620x264-jpg.1062522/ Or this http://i.imgur.com/ERcPjUW.jpg Having been thinking about tweeter grilles I could not come up with an ideal solution which did not undo some of t...
by karatestu
Wed Jun 30, 2021 7:29 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Thanks for your input Geoff and Rex. It's always good to have some engineers around. We have a saying in agriculture - "That'll be good enough for farming" :lol: Things get fixed with the big hammer. That doesn't cut it here however. This drawing shows nearly perfectly what I have planned....
by karatestu
Tue Jun 29, 2021 7:30 pm
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Up and down in a cube is good, I know that already as my latest prototype is exactly that. I would be nice to have a play around though.
by karatestu
Tue Jun 29, 2021 7:00 pm
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

As to stands, why not attach three legs to an oak ring then you can sit the speaker in the ring. That would be the logical thing to do. But I was getting all obsessive about having enclosures as smooth as possible because the mid bass are still producing output at 10kHz due to there being no electr...
by karatestu
Tue Jun 29, 2021 5:27 pm
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Either design has a high centre of gravity, you need to ensure that it will remain inside the footprint of the speakers. The wider the spacing of the feet the more stable the speaker. Thanks Geoff. I did realise that. I could make the legs from solid round brass bar as I have a load of it. That wil...
by karatestu
Tue Jun 29, 2021 8:04 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Rex or Geoff, what do you think of the following that J lifted from a manufacturers website "The internal volume of the enclosure is spherical which maintains an even pressure around the rear of the driver cone so the acoustic energy at lower frequencies is preserved". Has this been trans...
by karatestu
Tue Jun 29, 2021 6:59 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Rex or Geoff, what do you think of the following that J lifted from a manufacturers website

"The internal volume of the enclosure is spherical which maintains an even pressure around the rear of the driver cone so the acoustic energy at lower frequencies is preserved".
by karatestu
Tue Jun 29, 2021 6:42 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

The speaker in this thread is quite impressive. A full ranger in a 70 litre spun steel sphere which ended up in the headquarters of BBC Scotland

https://www.diyaudio.com/forums/full ... re.html
by karatestu
Tue Jun 29, 2021 6:34 am
Forum: DIY
Topic: Doc modding Marantz imperial 7
Replies: 1932
Views: 413939
Great Britain

Re: Doc modding Marantz imperial 7

Oops forgot to put link in to diyaudio thread

https://www.diyaudio.com/forums/mult ... e.html

It's 16 pages so anybody who wants to read it should have a spare half hour