Doc modding Marantz imperial 7

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Sat Dec 30, 2017 10:38 am

How is the new speaker cable, did you go to Les.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Sat Dec 30, 2017 12:23 pm

Speaker cable is fantastic Doc. It is definitely a grower as at first i did not know what was going on but i am becoming more and more aware of its loveliness as time goes on. Burn in or is it just more subtle ? The effect was not initially as large as when i added the TIS between cdp and pre. The Avondale speaker cables are very good but not so low on capacitance. The LS6 is a keeper for sure on sonic grounds alone but especially when playing about with removing poweramp zobel and output inductor (which i have not done yet).

Have not visited Les W yet but will do before the end of January.
Naim, Linn & Harbeth fanboy

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Sat Dec 30, 2017 12:52 pm

Pass the old codger :lol: my best. Us old codgers are getting less. The real guys who know something like Les and Colin are jewels in the hobby but they won't last for ever, there is a new one on the way up in Nick (Lurcher), but most are just knob heads like Arkwright and Serge. I haven't met open all hours, giz us a job, but met Serge when he had his shop back in the 80's, somewhere like Colchester of Chelmsford. Total knob head, can you imagine I am asked to visit with product, cannot get a word in edgeways and get a lecture on how to design amplifiers, even though he has never designed one. He just kept quoting and repeating Peter Walker of Quad. I think he even wore a white coat in the shop to show his status and brag about his technical ability. All he referred to was his test gear, mounds of useless lumps of metal just for his ego as he had learned how to use them. Obviously I (not so) politely left cursing the waste of time and petrol, and the amps were never even switched on. If anyone believes or takes seriously anything that man says they are up the wrong path - goodbye music.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Sat Dec 30, 2017 1:27 pm

Sure will Doc. Have you ever met Les ? Started his eectrical career down the pit. I think he is slightlyoder than you. Les deserves a medal for showing me and other Naim users the way to the light.

I thought Arkless was no spring chicken either ?
Naim, Linn & Harbeth fanboy

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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Sat Dec 30, 2017 1:58 pm

Nor is Colin or Serge, we are all old gits. Nick is the relative spotty young lad :lol: :lol: pretending to be father Christmas.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Fri Mar 16, 2018 10:28 am

Its bloody raining again :( At least it gives me some time to fanny about with sound system stuff :dance:

I noticed one of my 5" up firing mids was having an issue. I have suspected such for a while now. Changed amps over and speaker cables and it stayed on the right hand side only. A intermittent buzzing noise and less mid frequency from the affected driver - I think it caused the sound stage to shift slightly to the other side (left) unless the recordings are like that any way ?

Little cuboid semi Omni now has back off and 5" driver out. Funny thing is I used silicone sealant to stick it in and I am finding out now that it is a bit too sticky :angry-steamingears: I put clamps on so top and bottom panels could not move away from each other. Inserted small barrel car jack into the back of the speaker and jacked the bastard out :lol: :dance: Did not take much force to get it out. It will be going back in with decorators caulk as that is not as adhesive as silicone.

Put blue tack under the magnet and pointed the 5" upwards on top of the big bastard bass cube. Gave the thing a good blow out with my leaf blower. Then i noticed that the wires from the voice coil were against the back of the cone after they emerge from the black glue towards the centre of the cone. I have bent them away from the back of the cone and now playing music with driver still blu tacked to the BBBC.

It seems to have solved the problem as maybe the wires were vibrating on the back of the cone ?

Going to put Portishead Dummy on now as that CD really did show up the problem with lots of deep bass..........Playing it now and the problem seems to have gone away :dance: Just need to put the driver back in and check that things are still ok.
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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Fri Mar 16, 2018 10:33 am

Fairly common fault, always when fitting bass/mid driver those wires should be checked

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Fri Mar 16, 2018 10:43 am

Dr Bunsen Honeydew wrote:
Fri Mar 16, 2018 10:33 am
Fairly common fault, always when fitting bass/mid driver those wires should be checked
Cheers Doc, gives me peace of mind that I will have solved it. Off into the shed now to put the speaker back together (and have a cup of tea :grin: ).
Back later with the results.........................
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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Fri Mar 16, 2018 12:27 pm

Normal service now resumed. Playing music now proves it had a bigger detrimental effect than I thought. Sound stage and imaging back to how I remember it. No more annoying buzzes with bass heavy music. This crept up on me slowly rather than happened all of a sudden. I will be checking the other drivers next time I need to get them out. :guiness;
Naim, Linn & Harbeth fanboy

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Tue Aug 14, 2018 7:56 am

Been thinking about the final build of these speakers.

I thought about letting the mid driver share the enclosure with the bass (just for simplifying the construction as long as there is no detriment)but then remembered that there are 2 12 inchers in isobaric config. If the mid was sharing the volume with only one of the bass drivers surely this would feck the whole thing up ?
Naim, Linn & Harbeth fanboy

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