I will focus to achieve this.
I'm willing to attempt this. Try the mid-range open, and after testing continue with an enclosure depending on the sound. It will be neat to have the opportunity to hear both styles for the experience, plus it might save some work if it turns out okay.
Thanks!
My limited experience with small open baffles is that you do need to remove some if not most of the bass, so at a minimum you'll need a cap in series with the mid. Quick and dirty would be 100uF and 2mH on the little woofer and I'd keep the tweeter. Panasonic generally do know what they are doing; use a cheap capacitor tho, 50V more than adequate for this
Moondog55's "minimum" suggestion is shown in the schematic below.
(Note: The resistor R1 would only be required should the tweeter be too loud).
The system impedance would be 4 ohm.
A C2 of 100 uF would roll the 4 ohm twin cone in at around 400 Hz. C1 could be 3.3 uF to roll the 6 ohm tweeter in at around 8,000 Hz.
What value is the capacitor on your tweeter currently?
P.S. Both capacitors must be non-polar (NP) types designed for loudspeaker crossovers.
(Note: The resistor R1 would only be required should the tweeter be too loud).
The system impedance would be 4 ohm.
A C2 of 100 uF would roll the 4 ohm twin cone in at around 400 Hz. C1 could be 3.3 uF to roll the 6 ohm tweeter in at around 8,000 Hz.
What value is the capacitor on your tweeter currently?
P.S. Both capacitors must be non-polar (NP) types designed for loudspeaker crossovers.
Thanks, Moondog55 for the tip re: bass removal for an open design.
Galu, the image and notes make it understandable. I believe, based on what is visible on the capacitor, that it is the 4.7 axial one on this list: https://www.bennic.com.tw/en/acocap/10b25.asp
A theoretical side question, by removing a portion of a driver's capability, the bass from the midrange here, is there any appreciable loss of the potential of a speaker system? As in the full range of sounds capable of being made. Or do we not really notice or care because it is intended and there is no real loss in richness or range?
Galu, the image and notes make it understandable. I believe, based on what is visible on the capacitor, that it is the 4.7 axial one on this list: https://www.bennic.com.tw/en/acocap/10b25.asp
A theoretical side question, by removing a portion of a driver's capability, the bass from the midrange here, is there any appreciable loss of the potential of a speaker system? As in the full range of sounds capable of being made. Or do we not really notice or care because it is intended and there is no real loss in richness or range?
You may retain that Bennic 4.7 uF NP capacitor. It will roll in the tweeter in at around 5.5 kHz.
I do think that a 3.3 uF capacitor would be more suitable given that the twin cone driver has an extended high frequency response.
Regarding your side question:
The original configuration delivered a wide frequency range projection of sound from the front of the TV while bass frequencies were augmented by wall reflection from a rear firing woofer. I don't know if you intend to reproduce this forward/rear firing configuration.
Moondog55 refers to mounting the twin cone driver open baffle. His experience tells him that, in this situation, removing the lower bass from the twin cone driver is required. The speaker system will still reproduce the full range of audio frequencies.
However, you are undertaking DIY audio which provides a great opportunity to learn what's best for you by experimentation!
EDITED!
I do think that a 3.3 uF capacitor would be more suitable given that the twin cone driver has an extended high frequency response.
Regarding your side question:
The original configuration delivered a wide frequency range projection of sound from the front of the TV while bass frequencies were augmented by wall reflection from a rear firing woofer. I don't know if you intend to reproduce this forward/rear firing configuration.
Moondog55 refers to mounting the twin cone driver open baffle. His experience tells him that, in this situation, removing the lower bass from the twin cone driver is required. The speaker system will still reproduce the full range of audio frequencies.
However, you are undertaking DIY audio which provides a great opportunity to learn what's best for you by experimentation!
EDITED!
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Got it.
Forward for this one.
Got it.
Indeed! This is so great thanks again for the above!
Hmm, 'richness' historically could mean 'warmth' or 'fullness', so the cap would need to roll off below ~150 or ~250 Hz per this chart, ergo recommend experimenting initially in this range.
Thanks GM. I was thinking myself that 400 Hz was a tad too high!
I'll add that ~150 Hz and ~250 Hz would call for standard capacitor values of 220 uF and 150 uF respectively for cap C2.
@dncusa These values can be accommodated by bipolar (non-polar) electrolytic capacitors at reasonable cost.
Below, I give an example of such capacitor values from a UK supplier in order to inform your search (use the scroll down VALUE tab in the link):
https://willys-hifi.com/collections...lectrolytic-capacitors?variant=36271157870751
I'll add that ~150 Hz and ~250 Hz would call for standard capacitor values of 220 uF and 150 uF respectively for cap C2.
@dncusa These values can be accommodated by bipolar (non-polar) electrolytic capacitors at reasonable cost.
Below, I give an example of such capacitor values from a UK supplier in order to inform your search (use the scroll down VALUE tab in the link):
https://willys-hifi.com/collections...lectrolytic-capacitors?variant=36271157870751
I guestimated cap value based purely on probable cost to the OP and it's common use in little boxes for cheap 5.1 systems, otherwise I would have recommended using something bigger; such as the above 150 to 220uF caps. But if going to a cap that large I also think you would need a small inductor on the woofer
For folks that have room for relatively large caps, cheap paper in oil (PIO) caps with its better damping like the pioneers used have least distortion.
This "sounds" like what I generally prefer.
Great, thanks for translating.
Thanks for considering the cost. Any further opinion on an inductor that comes to mind?
Allow me to answer that.
For ~150 Hz: L= 3.9 mH (C2 = 220 uF)
For ~250 Hz: L= 2.5 mH (C2 = 150 uF)
Ferrite core inductors as close in value to those above as possible will do the job.
EDIT: L values updated for 'best' result.
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Gallu beat me to it; just bear in mind that values within 10% should work