Harrison Ford Filter Feeler

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I'd just like to chime in and say I'm very glad I built a pair of these.
So handy to have around.

Thanks a lot to you who made the project possible!
 
Hi guys, great project, extremely useful tools...

I wondered, any chance for an update, to add the 'bump' type resonance boost from the new harrison unit? I have found that the HPF (which is lovely) would be even nicer if I could dial in a bit of resonant just-above-the-cutoff lift ...

Could have implications for the 8 channel chassis, but...

If not, any brave takers on how to implement this solo...I can follow a picture and solder but adding to the circuit could see me jump 50 yards into the air and scatter myself over a large area
 
It already has a bump.  I don't know what the new unit does or doesn't add.  It may 'take away' instead. 
 
Thanks Doug! Looks like I need "MORE BUMP"

No idea how the new harrison box differs circuit wise from this - and i'm happy with how they sound, was just a musing...
 
Hi guys back again.

I've just built an 8 channel kit to go with the unit I got ready built and am ready to get to the PSU. I wondered whether I would be better off using an outboard PSU to avoid the noise issues Peterson talked about.

What should I consider or is it purely a case of finding a supply with the right capacity? I would prob just drill a hole in the back and use a locking connector of some sort connected to a 'line lump' as they call it.

Any insight welcome :) look forward to powering this beast and seeing if it beats the unit I have already which is def a little noisier than some of my pro pieces.
 
discocubist said:
Hi guys back again.

I've just built an 8 channel kit to go with the unit I got ready built and am ready to get to the PSU. I wondered whether I would be better off using an outboard PSU to avoid the noise issues Peterson talked about.

What should I consider or is it purely a case of finding a supply with the right capacity? I would prob just drill a hole in the back and use a locking connector of some sort connected to a 'line lump' as they call it.

Any insight welcome :) look forward to powering this beast and seeing if it beats the unit I have already which is def a little noisier than some of my pro pieces.

I put my power supply inside the 1u rack and it works great with no noise issues.  Pics of my build are in this thread a few pages back.  Here is a link to the power supply kit and the transformer I used. 

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2054502.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=Symmetric+1A+Power+Supply+Kit+%28+K8042+%29&_sacat=0

http://www.antekinc.com/an-0124-10va-24v-transformer/

You could still build these into an external box if it ended up being noisy mounted internally...


 
I have 2ch HFF
and both bypass-switches are not functioning right.
They're not latching, only working if I hold them in.
It's these kind: http://www.audiomaintenance.com/acatalog/AL-03-002_extended_info.html

Should I presume I need to replace them,
or can I fix them?
 
Anyone know if these will work properly with a +/- 16VDC supply? I have a 16V psu for my access 312 preamps and I'm wondering if I can just use a second output Jack to connect these filters to power from the same supply
 
mattmartin831 said:
Anyone know if these will work properly with a +/- 16VDC supply? I have a 16V psu for my access 312 preamps and I'm wondering if I can just use a second output Jack to connect these filters to power from the same supply

All the ICs are rated at Max +/- 18V DC. It should be fine.
 
I bought the Harrison Ford Filters case from collective cases. Do the High Pass and Low Pass values printed on this case match up with the taper of a linear pot or a reverse log pot?
 

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Just finished. Sounds great, really useful. 8)

Thanks to 12afael, Marcocet, Jensenmann and everybody who contributed to this nice project.

Front panel is from Frontpanels.de, and the psu is made from silent:arts pcb.

Pics:

jaLNABt.jpg


dhiir5U.jpg
 
Yes,well done!
I like the external psu.Should keep things quiet.
The pics' resolution seems a bit low,may I ask which way you went for i/o (THAT,INA,DRV etc.....?)?


Best regards,


Udo.
 

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