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Upgrades for 104s

 
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murphydog
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Joined: 17 Aug 2005
Posts: 9

PostPosted: Wed Aug 17, 2005 9:47 pm    Post subject: Upgrades for 104s Reply with quote

Hello I found this forum whilst searching the net for info about the 104 abs that I recently bought. I'm very pleased with them, speakers nowadays just don't seem to do it for me. Anyway, the drive units seem to be in very good shape but I was wondering if there are any no-brainer upgrades for the electronics? Cheers,Paul
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ColinR
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Joined: 31 Jul 2004
Posts: 1175
Location: Staffordshire

PostPosted: Thu Aug 18, 2005 6:50 pm    Post subject: Reply with quote

Quite easy if you are competent with a soldering iron. i.e. you can build one of the expensive "kits" sold at Maplins.

Read this http://www.falcon-acoustics.co.uk/Crossover%20Upgrade.pdf

Air cored inductors don't do much for the sound in KEF two-ways btw.

Investigate the 0.5 Amp Polyswitch as a fuse replacement for your T27.

Install some "man sized" speaker cable between the input terminals and the crossover.

Decide on how much you want to spend. A total recap, rewire & Polyswitch will be ~£80.

If you cannot solder go to evening classes and learn, or find a reliable friend who can solder neatly.

Keep all of the old bits and ensure the work is reversible as you might want to sell them on.
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murphydog
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PostPosted: Sun Aug 21, 2005 6:14 pm    Post subject: Reply with quote

Thanks, that gives me some food for thought. In the meantime, does anybody have suggestions for suitable stands for 104s? Thanks,Paul
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Gary
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Joined: 07 Nov 2004
Posts: 275
Location: Toronto, Canada

PostPosted: Mon Aug 22, 2005 1:22 am    Post subject: Reply with quote

I'm not sure if they made stands specifically for the 104.

As vibration is the enemy of quality sound, the stands / speakers should be isolated as much as possible. Generally speaking, wood stands would be the worse as they can vibrate.

If I were you, I'd try to find steel stands with hollow legs that you can fill with sand to weigh them down and stop vibration.

I'm not sure where in the world you are but partsexpress.com in Ohio USA has interesting items.... but I've never checked out their stands.

Good luck! Smile
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terry
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Joined: 22 Apr 2003
Posts: 262
Location: UK

PostPosted: Mon Aug 22, 2005 9:30 am    Post subject: Reply with quote

I am constantly questioning myself on this issue. Whether is better to damp the internal vibration and help it dissipate or whether one should be concentrating more on preventing incoming vibration. Different philosophies give different solutions including sinking spikes into the floor, or placing them on pods or large slabs of marble or concrete. Then we have: the spikes pointing up and the spikes pointing down issue; metal of wooden stands; sand or other fillings to the stands; etc etc. It to some extent boils down to individual choice about how you want the speakers to sound. Personally at this point in my life I go for the massive base of concrete with spiked speakers sitting on the concrete slabs. I have of course a chipboard floor. A concrete floor would be quite different.

I suspect that spiked 104abs would react quite well to being on a solid base of concrete - never mind stands.
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ColinR
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Location: Staffordshire

PostPosted: Mon Aug 22, 2005 1:01 pm    Post subject: Reply with quote

The 104aB's had dedicated trolly stands about 12" high as an option, so any stand suitable for Spendor BC1's or a similarly sized design will do Smile .

Having 1" thick wood block floors over concrete Very Happy .

I can and do use :

1. Spikes into self tapping screws.
2. Castors in castor cups screwed to the floor.
3. Heavy Target stands filled with urethane foam to prevent "ringing".
4. 5mm steel plates with nuts for sharpened 15mm dia bolts welded to them, screwed to the bases of my Cambridge R50's.
5. Bedside cabinets Shocked . Think about it, a rigid cavity resonator Cool .

It's all down to what "floats your boat" and what is practical from an engineering perspective.
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terry
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Joined: 22 Apr 2003
Posts: 262
Location: UK

PostPosted: Mon Aug 22, 2005 1:59 pm    Post subject: Reply with quote

Colin and I have just proved it - there is no single solution. My 'Naimee' ears are tuned to a particular sound and I believe that the sound can be enhanced in specific ways - hence my solution. You really just have to try possible options, listen and decide what you like.

Last edited by terry on Mon Aug 22, 2005 11:17 pm; edited 1 time in total
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Gary
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Joined: 07 Nov 2004
Posts: 275
Location: Toronto, Canada

PostPosted: Mon Aug 22, 2005 10:51 pm    Post subject: Reply with quote

Wow, there's never an absolute answer, is there? Very Happy
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harry h
Junior Contributor 20+


Joined: 15 Oct 2004
Posts: 24
Location: Kapiti coast. New Zealand

PostPosted: Tue Aug 23, 2005 9:11 am    Post subject: Reply with quote

I personally go along with Colins no 1 solution, ie speaker spikes sitting into the cross head of self tapping screws screwed down thru the carpet till the head is flush with the top of the carpet pile.
I liken the change in sound to the same difference you get in your cars handling when you inflate underinflated tyres,if you get my drift. Very Happy Imaging seems to snap into focus.
I allso cured a feedback problem i was getting with my Linn LP12 by using the same system under the Sound Organisation table it was sitting on.
This of course is presuming you live on suspended timber floors.

Cheers

H
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proffski
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Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Fri Aug 26, 2005 12:44 am    Post subject: Reply with quote

The ageing non polarised electrolytics will be well past their use by date.
Using non electrolytic capacitors is an expensive but most worthwhile upgrade. The cores will not saturate at sensible listening levels that the speakers will tolerate, using air cored inductors is tricky as the resistance will vary as well as other parameters. Again, used sensibly the fuses are not needed. I have had my 104aBs from new with never a problem yet.
Fuses were shorted out and within reason capacitors replaced.
Extra internal damping helped with some of the bass waffle as did damping pads on the back of the cabinet rear wall on the outside. Looks crap but helps the sound. Sadly as cuddly as they are these gorgeous creations will never be able to achive the SPLs and dynamics of modern monitors.

When first shown to the public the cut away cabinets out of interest had much thicker bitumous pads and more foam than the versions that went on sale. I was there at the opening! STUNNING!

Of course they were only the 104s then, the 104aBs came later...
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