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Tripmaster
2009-10-13, 10:28
Hi

This is my first post on this forum...so please go easy on me!

I am interested in buying a Touch but have a few questions before I get too excited.

I plan to use the Touch as the main source for my HI-FI and I have recently built some full range floor standing speakers.

I would like to know if there is any control over EQ with the Touch. My speakers currently use an inductor and I would like to remove this and control the baffle step electronically.

Here is a section taken from the speaker designers website...

'Digital EQ: I do the EQ within the music player. Foobar2000 has a 1/2
octave equalizer built in. The equalizers of both WMP and J. Rivers
have fewer bands. I don't know about WinAMP or anything else. 1/2
octave works OK, although I would like to see finer. It is reported to
me the the J. Rivers EQ works well with the LT-2000/DX3 and tubes.

Digital EQ, indeed any EQ needs to be handled with finesse. Too much
EQ will sound odd and fake. You will want to use the minimum amount of
EQ to balance the speakers and the room to your ears. Anything over
6dB is too much regardless of the particular problem. I spent the time
to EQ the speakers flat with an SPL meter. The result was a dull
recessed sound. The best way to start the EQ process is to set the
sliders to the inverse of the speaker and then play with it using your
favourite recordings until it sound right. '

Any help will be greatly appreciated! :)

Thanks

Richard

aubuti
2009-10-13, 10:36
At present the SBTouch does not have any EQ controls. I don't know if it would be possible to add any in the firmware at a later date. There is a plugin (Inguz) that provides EQ and digital room correction. To use the Inguz plugin you would need to be running the server software (Squeezebox Server) on a separate computer, not on the SbS software that is built-in to the SBTouch, because the plugin requires more computing resources than the SBTouch has.

Phil Leigh
2009-10-13, 10:37
Hi

This is my first post on this forum...so please go easy on me!

I am interested in buying a Touch but have a few questions before I get too excited.

I plan to use the Touch as the main source for my HI-FI and I have recently built some full range floor standing speakers.

I would like to know if there is any control over EQ with the Touch. My speakers currently use an inductor and I would like to remove this and control the baffle step electronically.

Here is a section taken from the speaker designers website...

'Digital EQ: I do the EQ within the music player. Foobar2000 has a 1/2
octave equalizer built in. The equalizers of both WMP and J. Rivers
have fewer bands. I don't know about WinAMP or anything else. 1/2
octave works OK, although I would like to see finer. It is reported to
me the the J. Rivers EQ works well with the LT-2000/DX3 and tubes.

Digital EQ, indeed any EQ needs to be handled with finesse. Too much
EQ will sound odd and fake. You will want to use the minimum amount of
EQ to balance the speakers and the room to your ears. Anything over
6dB is too much regardless of the particular problem. I spent the time
to EQ the speakers flat with an SPL meter. The result was a dull
recessed sound. The best way to start the EQ process is to set the
sliders to the inverse of the speaker and then play with it using your
favourite recordings until it sound right. '

Any help will be greatly appreciated! :)

Thanks

Richard

I think you will need the INGUZ plugin to do that sort of EQ

SuperQ
2009-10-13, 12:47
Can you post more info on those speakers? I'm not sure what the inductor you're talking about is doing. Normally I see inductors used as low pass filters in a crossover network. I don't think this could be done correctly with a single amplifier. You would need a bi-amp setup and the EQ work being done at the amplifier stage for the woofer.

Tripmaster
2009-10-13, 13:16
Can you post more info on those speakers? I'm not sure what the inductor you're talking about is doing. Normally I see inductors used as low pass filters in a crossover network. I don't think this could be done correctly with a single amplifier. You would need a bi-amp setup and the EQ work being done at the amplifier stage for the woofer.

Hi SuperQ

Its in fact a SuperQ iron core inductor

http://www.parts-express.com/iron-core-inductors-index.cfm

http://i374.photobucket.com/albums/oo189/Tripmaster_photo/SpeakerInductor.jpg

Tripmaster
2009-10-13, 14:05
At present the SBTouch does not have any EQ controls. I don't know if it would be possible to add any in the firmware at a later date. There is a plugin (Inguz) that provides EQ and digital room correction. To use the Inguz plugin you would need to be running the server software (Squeezebox Server) on a separate computer, not on the SbS software that is built-in to the SBTouch, because the plugin requires more computing resources than the SBTouch has.

Thanks for the Inguz recommendation, it looks like great software. I have been thinking about making a measurement mic for a while, and it will be nice to see how close my speakers are to the designers spec.

Its a shame the Touch needs to be connected to a PC, it kinda defeats the point in my case.

Thanks

Richard

aubuti
2009-10-13, 14:38
Thanks for the Inguz recommendation, it looks like great software. I have been thinking about making a measurement mic for a while, and it will be nice to see how close my speakers are to the designers spec.

Its a shame the Touch needs to be connected to a PC, it kinda defeats the point in my case.
You're welcome. Please note that in general the SB Touch does not need to be connected to a PC. It can run the server software on its own. However, the Inguz is by far the most resource-demanding plugin available for the SB, and needs a sufficiently powerful PC to run it. Putting that kind of computing power in the SBT would drive up the cost, size, and noise of the SBT considerably, for a plugin that only a small percentage of users would ever use. You can have Inguz, or you can have PC-less operation, but you can't have both.

EDIT: Also note that if you use Inguz, the pc doesn't need to be anywhere near the SBT. It just has to be somewhere on your home network. Plenty of people stick the pc in a closet, basement, or utility room. You're probably aware of this, but thought I'd mention it just in case.

amcluesent
2009-10-15, 14:02
Unfortunately the Inguz plugin isn't currently functional with the 7.4.x release of Squeezebox Server.

http://forums.slimdevices.com/showthread.php?t=68618

SuperQ
2009-10-15, 15:53
Hi SuperQ

Its in fact a SuperQ iron core inductor

http://www.parts-express.com/iron-core-inductors-index.cfm

http://i374.photobucket.com/albums/oo189/Tripmaster_photo/SpeakerInductor.jpg

What I really wanted was the link to the speaker designer's site.

From what what you describe in your diagram you are using the inductor as a crossover filter. I'm fairly sure no digital EQ would work in this situation.

I really need a full source to speaker design from the original site.

Tripmaster
2009-10-27, 14:37
What I really wanted was the link to the speaker designer's site.

From what what you describe in your diagram you are using the inductor as a crossover filter. I'm fairly sure no digital EQ would work in this situation.

I really need a full source to speaker design from the original site.

Hi Sorry for the delay, I haven't visited the forum for a while...but I am please to say I have pre-ordered a Touch :)

Here is the link to the speaker site

http://www.geocities.com/rbrines1/

If I used digital EQ I would remove the inductor from the speakers

Regards

Richard

JohnSwenson
2009-10-29, 16:13
From the description this looks like a Baffle Step Correction (BSC) circuit. This compensates for the decrease in bass response when putting a woofer designed for a wide baffle into a narrow baffle.

Its not a crossover, its not tailoring the response between two drivers, but tweaking the bass response of the woofer.

You can implement this with passive components between the amp and speaker (as in the digram), with passive components between the source and amp or with digital EQ.

I do this with my speakers using a simple RC network between the preamp and power amp, its generally much better than the passive between the amp and speaker. It also has the advantage that you can use a pot in the circuit and tweak it to get just the response you want.

For the OP if you want to use the builtin server of the Touch there is no way you are going to be able to run the EQ plugin, but the RC circuit between the Touch and amp might be a good choice.

John S.

Tripmaster
2009-10-30, 01:04
From the description this looks like a Baffle Step Correction (BSC) circuit. This compensates for the decrease in bass response when putting a woofer designed for a wide baffle into a narrow baffle.

Its not a crossover, its not tailoring the response between two drivers, but tweaking the bass response of the woofer.

You can implement this with passive components between the amp and speaker (as in the digram), with passive components between the source and amp or with digital EQ.

I do this with my speakers using a simple RC network between the preamp and power amp, its generally much better than the passive between the amp and speaker. It also has the advantage that you can use a pot in the circuit and tweak it to get just the response you want.

For the OP if you want to use the builtin server of the Touch there is no way you are going to be able to run the EQ plugin, but the RC circuit between the Touch and amp might be a good choice.

John S.

Thanks John

Merlinwerks
2009-11-04, 16:26
What I really wanted was the link to the speaker designer's site.

From what what you describe in your diagram you are using the inductor as a crossover filter. I'm fairly sure no digital EQ would work in this situation.

I really need a full source to speaker design from the original site.

The speaker is a single driver full-range design, the inductor and resistor in parallel in series with the driver is a simple baffle step compensation filter (BSC). Because at a point in the lower frequencies, which is related to baffle width you will experience ~ 6db drop in output which will accentuate the higher frequencies and the speaker will sound unbalanced. The BSC filter is used to shelve down the high end a bit to return a more balanced sound the speaker.

Ooops! I missed reading the second page before I posted...

Anyway, HERE (http://www.t-linespeakers.org/tech/bafflestep/passive-BSC.html) is some info on implementing a passive line-level BSC filter.