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 » Mon Dec 11, 2017 3:30 pm

You have one of the very very few proper, as the inventor envisaged, isobaric systems in the world. Everyone else has the Linn balls up version or copies of it.

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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Mon Dec 11, 2017 4:43 pm

Well that is all thanks to you doc, otherwise I would have fecked it up and done it as I read elsewhere. :guiness;
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Tue Dec 12, 2017 4:51 pm

Big old bass cubes back up and running cos I have completed two of my regulated front end power amps. :dance: :dance: Put it on the mid range for now.

Output stage has 350VA to schottky rectifiers to 6 x 10,000uf caps to amp board (54V)
Input stage has 50VA (for now) to soft recovery rectifier diodes to 6 X 4,700uf caps to Avondale regulator board to amp board (47V)

It took me a while to do as this was my first time splitting the stages in a poweramp :pray: Triple checked everything and turned on with a broom handle (only joking). I was a bit nervous though. Apparently there is more chance of DC getting to the drivers if the front end is split off and it fails ..gulp.

I am very impressed by what has happened with this :dance: I put the first two completed on the mid range as I thought I would get most benefit from starting there. Next will be the tweeter monoblocs. I don't know if the bass will get done as I don't have enough regulator boards to do it but I could split them off and give separate psu's without regulators. Maybe I could swap the tweeter amps on to the bass and see if it is worthwhile there too before hassling les at Avondale for two more regulator boards.

Onward to the next two monoblocs........................
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Dec 13, 2017 11:34 am

NOT SPEAKER RELATED AS SUCH

I have done some more listening and this regulated front end lark is well worth doing. I am hearing more detail for sure especially low level stuff. Listening to Chemical Brothers - we are the night I am suddenly more aware of the sound effects they have used especially on sounds which are low in the mix. Echoes of reverb are especially unlocked now. This is a highly electronic album (some real instruments on it) and of course there are lots of effects used. When a passage of music suddenly stops it drops in to complete silence but before that happens you can hear much more of the sound effects tailing off in to the silence.

Giving the front end it's own psu and regulator is like putting a velvet glove on an iron fist.

The higher NVA power amp models give the front end it's own psu but don't use a regulator. They also give the front end a big toroid even though the current draw of an input stage is usually very low (mine is 12mA). I must try giving my front ends a big ass toroid as well and try without a regulator. I can't try without a regulator at the moment because the transformers I have give me too much voltage.

More later.............
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Dec 20, 2017 9:44 am

LS6 cables have arrived Doc :dance: many thanks .

Checked for continuity and all is good , no breakages on transit.

Currently hooking them up...................................
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Dr Bunsen Honeydew
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Wed Dec 20, 2017 2:54 pm

:epopc:

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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Dec 20, 2017 4:02 pm

You are not having them back :grin:
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Re: Doc modding Marantz imperial 7

Unread post by Dr Bunsen Honeydew » Wed Dec 20, 2017 4:31 pm

:think: why :whistle:

:animals-chickencatch:

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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Wed Dec 20, 2017 4:59 pm

I will comment more when I have done more listening.

What I can say now is that as ever with NVA it is all about the music - there is more of it. It improves things over my Avondale blacklink cable in key areas.

There is more space, instruments sound more like real instruments. I have noticed some bass lines much easier to follow. There is more information present but in a subtle, not in your face way. More lovely textures to synth's and bass. I noticed the sound of a snare drum earlier which clearly was not being hit in the centre of the skin where as before it was masked. The space around instruments is clearer and decay of notes more detailed.

I will do a proper review (talking about the music) for the review thread in a week or two when any burn in will have probably finished. I like it a lot - there is more to hear but it is less fatiguing than before if that makes sense.

Busy listening to CD after CD which is a good thing :dance:

Edit - I reverted from triamping to biamping for this and it is clearly better than triamping with the old cables (not NVA amps though)
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Re: Doc modding Marantz imperial 7

Unread post by karatestu » Thu Dec 21, 2017 4:56 pm

Listening to Nick Drake. River man is a beautiful track which often gets the hairs on the neck standing up. No exception this time, if anything the hairs are not coming back down. There is much on this song to tickle the emotions. His voice of course, the guitar playing style the 5/4 time signature and the lovely string part. I have never heard Nick's voice so clear - every little warble is evident. Wow .
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