consider an OB... you won't be disappointed
if the Q of the more efficient driver is around 1 (look at the FR 8 JS 8 OHM) , then try an OB. Then whatever woofer in whatever size box for the bass. As long as the Xover is 2nd order, and at least 2X's the low end limit of the OB, you should have something very enjoyable. And power is really not an issue, or a problem as something like 75% of the power requirded to drive a loudspeaker system is used below 60Hz...top end use 10-20 watts/ch, bottom end 100-150w/ch for the woofs
I do love OB speakers.
if the Q of the more efficient driver is around 1 (look at the FR 8 JS 8 OHM) , then try an OB. Then whatever woofer in whatever size box for the bass. As long as the Xover is 2nd order, and at least 2X's the low end limit of the OB, you should have something very enjoyable. And power is really not an issue, or a problem as something like 75% of the power requirded to drive a loudspeaker system is used below 60Hz...top end use 10-20 watts/ch, bottom end 100-150w/ch for the woofs
I do love OB speakers.
Last edited:
I've not thought about using OB much, but there's two problems with the above mentioned driver.
One is efficiency
Two is finding it in the UK - I can get the frs8m, which is a good start, as the 88dB 1w/1m efficiency means it would be more suited to the woofer in question.
Perhaps I should explain. I have two stereo amps. One (will be) bridged, and used with a subwoofer. The second is a better quality amp, which I usually use with my mains. So you see, I usually try to find a way to make it usable with one amp.
The Q of the more efficient one (frs8m) is 0.49, with a Qms of over 3. The Q of the less efficient one (frs8) I already have is over 1, and I've tried that on small baffles, with another (in a sealed box) to cancel the rearwaves.
Thanks for the interest.
Chris
One is efficiency
Two is finding it in the UK - I can get the frs8m, which is a good start, as the 88dB 1w/1m efficiency means it would be more suited to the woofer in question.
Perhaps I should explain. I have two stereo amps. One (will be) bridged, and used with a subwoofer. The second is a better quality amp, which I usually use with my mains. So you see, I usually try to find a way to make it usable with one amp.
The Q of the more efficient one (frs8m) is 0.49, with a Qms of over 3. The Q of the less efficient one (frs8) I already have is over 1, and I've tried that on small baffles, with another (in a sealed box) to cancel the rearwaves.
Thanks for the interest.
Chris
The last time I bi-amped, it was with the high quality amp on the mid/high, and the subwoofer amp on the woofers.
The ratings are as follows:
HQ amp - 75W/ch
LQ amp - 50W/ch.
However, the HQ amp hits 10%THD at 60W into 4 ohm for both channels.
The LQ amp will push 14dB of LT gain and cause the speakers to bottom out before clipping (with a sealed box, this is an achievement). So, where does that leave us?
Chris
The ratings are as follows:
HQ amp - 75W/ch
LQ amp - 50W/ch.
However, the HQ amp hits 10%THD at 60W into 4 ohm for both channels.
The LQ amp will push 14dB of LT gain and cause the speakers to bottom out before clipping (with a sealed box, this is an achievement). So, where does that leave us?
Chris
Super Tweeters...
I know I've been posting a lot recently, but I've had a brainwave...
Would adding a supertweeter (8kHz upwards) to stop beaming be a good idea?
I ask because, looking at the dispersion characteristics of the FR drivers I've chosen, they beam a lot higher up the frequency range, so I wondered if I should just cope with it, or add a crossover and tweeter?
Thanks in advance
Chris
I know I've been posting a lot recently, but I've had a brainwave...
Would adding a supertweeter (8kHz upwards) to stop beaming be a good idea?
I ask because, looking at the dispersion characteristics of the FR drivers I've chosen, they beam a lot higher up the frequency range, so I wondered if I should just cope with it, or add a crossover and tweeter?
Thanks in advance
Chris
Here's another version of the Tysen, made by Visaton themselves:
Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories
Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories
Hi Chris, thanks for modelling (post 14), do you modellig it for sealed box or BR?
BR is what I don't want any more.
For your project, I think you worry too much about drivers efficiency and SPL.
I use my Cyburgs Needles with FRS8 and 10W T-amp in 30sq/m room. Maybe sometime, wen I want to listen bassy music, like reggae very loud, there is little not enough.
But if you cut RFS8 at 200-300hz, you can go loud and clean. Just go active, be amping.
You can get quality amp for cheap, buying and a little bit modifying this:
MKll Tripath TA2024 fully finished&tested pcb 2x15watt - eBay (item 250500639848 end time Oct-18-09 04:48:33 PDT)
Or without modification this:
New Version MKIII Tripath DIY Audio TA2024 PCB - eBay (item 250512142377 end time Oct-15-09 20:08:06 PDT)
and connect it to this:
12V 2A DC Universal Regulated Switching Power Supply - eBay (item 280344252845 end time Nov-06-09 17:59:18 PST)
BR is what I don't want any more.
For your project, I think you worry too much about drivers efficiency and SPL.
I use my Cyburgs Needles with FRS8 and 10W T-amp in 30sq/m room. Maybe sometime, wen I want to listen bassy music, like reggae very loud, there is little not enough.
But if you cut RFS8 at 200-300hz, you can go loud and clean. Just go active, be amping.
You can get quality amp for cheap, buying and a little bit modifying this:
MKll Tripath TA2024 fully finished&tested pcb 2x15watt - eBay (item 250500639848 end time Oct-18-09 04:48:33 PDT)
Or without modification this:
New Version MKIII Tripath DIY Audio TA2024 PCB - eBay (item 250512142377 end time Oct-15-09 20:08:06 PDT)
and connect it to this:
12V 2A DC Universal Regulated Switching Power Supply - eBay (item 280344252845 end time Nov-06-09 17:59:18 PST)
Yes I see at this too before, only one thing that I hate in this design - this is BR.
Can you simulate, what happens in this enclosure size with closed ports - sealed box?
Well, not to be overly pedantic about it, but one of the main features of the Tysen design would be the tapered TL enclosure for the mid-range/tweeter. As Dave had posted earlier in this thread, that certainly has an effect on the driver's working impedance. Depending on the selected drivers and XO point of variations on this design, this could impact design of XO & EQ/ BSC network.
Let's not get into technicalities.
Looks like I could use the exact same TL (impedance peak in the same place) and get similar results, with the FRS8M, which is a good thing. I have no idea about how to go about designing a TL of any kind. I just know that there's been lots of contradictory opinions on here about them.
Chris
Looks like I could use the exact same TL (impedance peak in the same place) and get similar results, with the FRS8M, which is a good thing. I have no idea about how to go about designing a TL of any kind. I just know that there's been lots of contradictory opinions on here about them.
Chris
From what I have gathered it is as simple as making the enclosure cross section taper from 10:1. That is from baffle:vent. The internal width of the Tysen is the same front to rear so the height of the TL that the FF85K is in goes from 10 to 1 ratio.
I don't know if this took some serious calculating or if it works this way for many drivers. I'm considering it for some TangBand W4-1320 FR drivers I have. Would the box volume and vent dimension stay the same as is calculated for a typical vented box, just make it taper 10:1 from baffle to vent?
I don't know if this took some serious calculating or if it works this way for many drivers. I'm considering it for some TangBand W4-1320 FR drivers I have. Would the box volume and vent dimension stay the same as is calculated for a typical vented box, just make it taper 10:1 from baffle to vent?
No serious calculations were done. As it is a midrange TL, being damped aperiodically, with line level XO at least an octave above the remaining prime resonance, it is not super critical. Dimensions were primarily determined by the space available once other considerations were taken into account.
A strong taper was used to push the primary resonance as low as possible given the available length. The actual TL volume could be larger.
As i work on a version with a passive XO i will work to develop a more optimum TL to get the impedance even flatter, but one could easily work with what is there.
dave
Hi chris661,
I've been following this thread and hope you don't mind if I ask a quick question, which UK supplier are you sourcing your FRS8M's from?
I'm also quite interested to see how your project works out because I'm thinking of putting together a new set of speakers and having previously built a pair of these Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories and been impressed with the Visaton drivers, your project caught my eye. So good luck with the build and keep us posted
Regards,
Ewan
I've been following this thread and hope you don't mind if I ask a quick question, which UK supplier are you sourcing your FRS8M's from?
I'm also quite interested to see how your project works out because I'm thinking of putting together a new set of speakers and having previously built a pair of these Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories and been impressed with the Visaton drivers, your project caught my eye. So good luck with the build and keep us posted
Regards,
Ewan
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.