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Old 6th November 2012, 08:59 PM   #11
sreten is offline sreten  United Kingdom
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Hi,

Apparently the speakers feature a "low cut filter"
for use with an optional "LF-S8" subwoofer.
The manual is as clear as mud.

rgds, sreten.
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Old 6th November 2012, 11:24 PM   #12
djk is offline djk
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Solved.
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Old 7th November 2012, 12:02 AM   #13
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Quote:
Originally Posted by PsychoM View Post

Will it sound bad if I use the sub without filtering the line out (so both the sub AND the monitors will put out the low frequencies)?
Is there an easy way to filter the line out? I think it is a buffered line out with an opamp, so if just add some caps, will that do the trick?

Thanks,
Psycho
I sit most nights listening to an 18 inch sub playing full range music.
Obviously the highs are a bit lacking but its passable.

Look up Sallen and Key and Butterworth op amp filters.
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Old 7th November 2012, 01:13 PM   #14
PsychoM is offline PsychoM  Belgium
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Quote:
Originally Posted by sreten View Post
Hi,

Apparently the speakers feature a "low cut filter"
for use with an optional "LF-S8" subwoofer.
The manual is as clear as mud.

rgds, sreten.
Not true!
The monitor speakers (Tascam VL-A5) do feature a low cut filter, but cutoff frequency is 500 hz! I have no idea why that frequency is so high, but it's way too high if you're just adding a sub!

The LF-S8 has an indepent crossover. It has stereo HF outputs (for the monitors), and an LF output for an extra sub. When using the LF-S8, there is no need to use the low cut on the VL-A5s.

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Old 7th November 2012, 01:33 PM   #15
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Quote:
Originally Posted by PsychoM View Post
Not true!
The monitor speakers (Tascam VL-A5) do feature a low cut filter, but cutoff frequency is 500 hz! I have no idea why that frequency is so high, but it's way too high if you're just adding a sub!
Might be a typographical error, Donkey Kong was supposed to be Monkey Kong...
Have you tried the "500 Hz" low cut switch to hear if it might be a mis print of a 50 Hz cut?
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Old 7th November 2012, 01:33 PM   #16
djk is offline djk
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" but it's way too high if you're just adding a sub!"

And what is stopping you from going in and changing a couple of resistors?

This is DIY audio.

"Have you tried the "500 Hz" low cut switch to hear if it might be a mis print of a 50 Hz cut? "

Probably correct.
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Old 7th November 2012, 03:17 PM   #17
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Quote:
Originally Posted by djk View Post
" but it's way too high if you're just adding a sub!"

And what is stopping you from going in and changing a couple of resistors?

This is DIY audio.

"Have you tried the "500 Hz" low cut switch to hear if it might be a mis print of a 50 Hz cut? "

Probably correct.
Thinking about it, a 150/80 Hz "LF contour" would make sense, 150/800 Hz not very much, one seldom sits down in front of a pair of near field monitors and says "sounds good, if only for that midrange bit around 800 Hz being 1.5 dB too much..."

If they were my pair, first thing I'd do is make sure the volume pot was labeled "0-11".

Last edited by weltersys; 7th November 2012 at 03:21 PM.
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Old 7th November 2012, 07:08 PM   #18
PsychoM is offline PsychoM  Belgium
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Quote:
Originally Posted by weltersys View Post
Might be a typographical error, Donkey Kong was supposed to be Monkey Kong...
Have you tried the "500 Hz" low cut switch to hear if it might be a mis print of a 50 Hz cut?
I tried it, and it's definitly not a 50 Hz cut. I can hear it clearly cutting @ 200 Hz, and I can hear it has a minor difference @300 Hz. It's difficult to A/B test it because the dipswitches are very hard to reach.

The 800 Hz is, as far as I can hear, right too.

It would also be strange if Tascam, not an unknown company, would write the specs wrong on the product itself, in the manual, and on their web page, for 2 generations of an entire monitor range (VL-X* and VL-A*).
But I still wonder why they have chosen a cutoff frequency that high...
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Old 7th November 2012, 08:01 PM   #19
sreten is offline sreten  United Kingdom
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Quote:
Originally Posted by PsychoM View Post
Not true!
The monitor speakers (Tascam VL-A5) do feature a low cut filter, but cutoff frequency is 500 hz! I have no idea why that frequency is so high, but it's way too high if you're just adding a sub!

The LF-S8 has an indepent crossover. It has stereo HF outputs (for the monitors), and an LF output for an extra sub. When using the LF-S8, there is no need to use the low cut on the VL-A5s.

But I still wonder why they have chosen a cutoff frequency that high...
The marketing blurb with the speakers says its for use with the LF-S8.

Why I said "Apparently". Doesn't make a lot of sense, manual is rubbish.

Neverless it should work well with two subs, stereo or mono, set quite
high, the high x/o point maximises the available volume capability.

Or double the capacitor values in that part of the circuit.

rgds, sreten.
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Old 7th November 2012, 09:35 PM   #20
tb46 is offline tb46  United States
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Hi,

Here is a schematic: Tascam VL-X5 schematic and service notes - Home Recording forums

You'll have to join to download.

Regards,
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