JPW P1 Doc Mods

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Daniel Quinn
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Re: JPW P1 Doc Mods

Unread post by Daniel Quinn »

I knew you would say that :lol:

I like the double security

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Quarknosis
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Re: JPW P1 Doc Mods

Unread post by Quarknosis »

Daniel Quinn wrote:"DQ, can you tell me how much difference there is in size between the original JPW driver and the Doc Mod version and how you fixed it in place please. "

They fit fine. The only problem is the frame for the drivers as a smaller diameter, It is about 5mm smaller and so they do not fit the original screws holes and leave these exposed . This was a slight problem for me ,because mine are light oak veneer and so I filled them in with appropriately shaded wood filler. With your being black painted it will be somewhat easier to fill in and hide .

I fixed then in place with a combination of wood screws and sealant to make them air tight .
Thanks for that, excellent info :grin:
Main System. Amp - Luxman LV-120, CD - Pioneer PDX505 & Hitachi DA 401. Turntable - Trio KD-2055/Denon DL-110 & Ortofon VMS20E. Cassette Deck - JVC KD A55. Speakers - Arcam Alpha connected with NVA LS3.

Headphone System - Little Dot Mkiii headphone amp, various vintage CD players into NVA P50 with Sennheiser HD600 and Beyer DT 880

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Quarknosis
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Re: JPW P1 Doc Mods

Unread post by Quarknosis »

Dr Bunsen Honeydew wrote:Not needed just use Bison Kit to fit the drivers.
A couple of daft questions,
1. Would I apply the Bison Kit to each surface, or just one of them?
2. Regarding the resistor and capacitor, does it make any difference which is first in signal path? I don't think it does but want to make sure.
Main System. Amp - Luxman LV-120, CD - Pioneer PDX505 & Hitachi DA 401. Turntable - Trio KD-2055/Denon DL-110 & Ortofon VMS20E. Cassette Deck - JVC KD A55. Speakers - Arcam Alpha connected with NVA LS3.

Headphone System - Little Dot Mkiii headphone amp, various vintage CD players into NVA P50 with Sennheiser HD600 and Beyer DT 880

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Dr Bunsen Honeydew
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Re: JPW P1 Doc Mods

Unread post by Dr Bunsen Honeydew »

1 one or both doesn't matter, I just use one. But it has to be left magnet downward overnight for it to set hard.
2 doesn't matter.

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Quarknosis
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Re: JPW P1 Doc Mods

Unread post by Quarknosis »

Dr Bunsen Honeydew wrote:1 one or both doesn't matter, I just use one. But it has to be left magnet downward overnight for it to set hard.
2 doesn't matter.
Thanks Doc :grin:
Main System. Amp - Luxman LV-120, CD - Pioneer PDX505 & Hitachi DA 401. Turntable - Trio KD-2055/Denon DL-110 & Ortofon VMS20E. Cassette Deck - JVC KD A55. Speakers - Arcam Alpha connected with NVA LS3.

Headphone System - Little Dot Mkiii headphone amp, various vintage CD players into NVA P50 with Sennheiser HD600 and Beyer DT 880

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Re: JPW P1 Doc Mods

Unread post by Quarknosis »

I finally had chance to do a little bit more with these speakers yesterday so I took the crossover out and replaced it with just the resistor and Clarity cap to the tweeter.

Initial impressions were mainly excellent, voices sounded more expressive than before, tone, timbre and detail were more apparent, individual instruments seemed to stand out more and the interplay between different parts was improved. At first I felt that the bass level was a little bit lower than the midrange but that might just have been the CD that I played first. I wonder how much of the improvement is down to getting rid of the electrolytic cap and how much is down to removing the inductors?

Over the few hours that I listened yesterday I didn't get the feeling that the Mid/bass unit needs any further damping very often, but occasionally there seemed to be something that I couldn't quite put my finger on, not quite shrillness but a feeling that the music was a little bit forced at times.

I'll be giving more time for the resistor and cap to settle in and listening as much as possible before doing anything else but any info that will help resove impression of the music being forced is appreciated.
Main System. Amp - Luxman LV-120, CD - Pioneer PDX505 & Hitachi DA 401. Turntable - Trio KD-2055/Denon DL-110 & Ortofon VMS20E. Cassette Deck - JVC KD A55. Speakers - Arcam Alpha connected with NVA LS3.

Headphone System - Little Dot Mkiii headphone amp, various vintage CD players into NVA P50 with Sennheiser HD600 and Beyer DT 880

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Dr Bunsen Honeydew
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Re: JPW P1 Doc Mods

Unread post by Dr Bunsen Honeydew »

Dope the bass mid driver.

As an initial tune up you should reset the speakers to the room. Take them right back to the wall. Move them forward by inches until the bass cleans up, if you start getting the mid hardness then you have come too far out. Having got the balance right then toe in until you get the image you want. You need to do this process again when you dope the bass driver.

I forget have you steel plated the cab, if not you have more progress to make. I presume you have removed all wadding as well.

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Quarknosis
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Re: JPW P1 Doc Mods

Unread post by Quarknosis »

Yesterday I moved them back to about 3 inches from the wall which was as close as I could get them, they were about 8 inches out before that. The bass filled in nicely so I gave them toe in to face me directly at the listening spot which seemed to help imaging a little bit. I know I need to spend more time getting the set up right by doing it in smaller steps, but I didn't have much opportunity to get any further yesterday.

The wadding has already been removed and steel plate fitted for some time now. I'll be investing in some Plasti-dip and possibly some Bison Kit as well, or I might use UHU instead, and have a go at doping the drivers myself when I have some time available.
Main System. Amp - Luxman LV-120, CD - Pioneer PDX505 & Hitachi DA 401. Turntable - Trio KD-2055/Denon DL-110 & Ortofon VMS20E. Cassette Deck - JVC KD A55. Speakers - Arcam Alpha connected with NVA LS3.

Headphone System - Little Dot Mkiii headphone amp, various vintage CD players into NVA P50 with Sennheiser HD600 and Beyer DT 880

Daniel Quinn
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Re: JPW P1 Doc Mods

Unread post by Daniel Quinn »

The drivers are already doped paper.

Will doping them further be beneficial ?

From my experience - all the doc mods made improvements and I preferred the JPW ap2 to the doc mod wharfedale diamond 10.3 I had . But I missed the snap and dynamism of the wharfedales which I put down to the smaller driver size and Kevlar cone material.

By comparison the paper driver sound slow with less rhythmic attack . As if the muscians were tired . Solution

Doc drivers to replace the papers ones . The JPW Ap2 drivers are 180 quid a pair new , so you may be able to sell them if they are in good nick .

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Dr Bunsen Honeydew
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Re: JPW P1 Doc Mods

Unread post by Dr Bunsen Honeydew »

Not the same DQ. The JPW cone is very lightly doped, it will have little to no effect on frequency response. Doc Mod doping is to remove the need for a crossover on the bass driver by tailoring its FR with the doping, so massively more doping is applied than in this case..

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