Cyril - As much as I love the FH3/XL , judging from the photo in other thread, I'd have suggested a Pensil over the horn, regardless of driver. In that tight a location, the A7.3 or Pluvia would likely provide sufficient low end, and if you could swing a small sub, so much the better.
Thanks chrisb,
I didn't know that FHs really need space around the sides. Doesn't that conflict with a typical corner loading scenario? For example, if optimally loading a Fostex driver in an FH3 how would you get space around the sides?
I must admit, speaker design is mysterious to me, but it seems to me also that in this room with the hip roof, I have reasonable space behind (so long as speaker not too high), quite a bit of height if I want it (so long as speaker not too deep), but limited space at sides due to obstacles. If seeking deepish bass, it seems a shame to use a stand mounter, when the volume used by the stand might just as well be used for the cabinet. WAF not a consideration here, lucky for me! I'm a little confused. I'm glad you've got an eye on cost though. Its good.
I didn't know that FHs really need space around the sides. Doesn't that conflict with a typical corner loading scenario? For example, if optimally loading a Fostex driver in an FH3 how would you get space around the sides?
I must admit, speaker design is mysterious to me, but it seems to me also that in this room with the hip roof, I have reasonable space behind (so long as speaker not too high), quite a bit of height if I want it (so long as speaker not too deep), but limited space at sides due to obstacles. If seeking deepish bass, it seems a shame to use a stand mounter, when the volume used by the stand might just as well be used for the cabinet. WAF not a consideration here, lucky for me! I'm a little confused. I'm glad you've got an eye on cost though. Its good.
Having said that, if I build a Pencil/Pluvia, along with the FH3/Fostex that I will soon have completed, I can do a good bit of experimentation in different locations without having spent a great deal of cash. I will then have gained a lot more practical knowledge, which is what I really want here.
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Thanks chrisb,
I didn't know that FHs really need space around the sides. Doesn't that conflict with a typical corner loading scenario? For example, if optimally loading a Fostex driver in an FH3 how would you get space around the sides?
As you move the FH3 out from the wall/corner (it can go almost right up to it) you lose bass gain and the point where the horn is impedance matched increases in frequency. The amount of damping can deal with the 1st.
We typically run ours the thickness of the deflector/woof out from the wall.
dave
Yes, I understand I think. The effective horn mouth area goes down as you come out from the corner/wall is another way of saying your point about frequency I think. But what of closeness to side wall? Does getting closer to the side wall tend to screw up the stereo image in your experience?
Cyril - it's the very asymmetrical loading on the outside boundaries, and the tapered cavity on the right side that I'd be concerned about.
As I said before, as much as I love the FH3s, I consider them to have some room placement requirements that a more conventional front firing monopole doesn't. On the few occasions I've set up FH3, or Hornshoppe Horn, or Buschhorn MKI, in my own home, I try to get them oriented as symmetrically as possible with regards to the side / back walls, That doesn't necessarily mean at exactly 45dg diagonally in the corner, but with as close to equal amounts of clear space on the sides - in other words, mirror imaged in terms of toe-in to the primary listening position.
As I said before, as much as I love the FH3s, I consider them to have some room placement requirements that a more conventional front firing monopole doesn't. On the few occasions I've set up FH3, or Hornshoppe Horn, or Buschhorn MKI, in my own home, I try to get them oriented as symmetrically as possible with regards to the side / back walls, That doesn't necessarily mean at exactly 45dg diagonally in the corner, but with as close to equal amounts of clear space on the sides - in other words, mirror imaged in terms of toe-in to the primary listening position.
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Regarding the Pluvia 7 you kindly suggest (CHS-70A I think), Bigun asks on the Markaudio CHS-70A Extended Full Range audio driver thread, are any enclosure designs available? Planet10 says on 12th Jun 2016:
There is no Pensil cabinet for the CHS-70A yet on Frugal Phile that I can see, do you think then to try the driver in the Pensil R70.3 cabinet would likely be OK? To the untrained eye, the CHS-70A and CHR-70.3 Thiele/Small parameters look quite close... I expect there are other mysterious considerations too!
[1] http://www.diyaudio.com/forums/twin-audio/280700-markaudio-chs-70a-extended-full-range-audio-driver.html
[2] http://www.creativesound.ca/pdf/CSS-EL70-data-080909.pdf
[3] http://www.markaudio.com/Archive/item/download/99_41ab22e79d2101506d131f937e60ae9d
[4] http://www.creativesound.ca/pdf/CHR70introduction.pdf
* Maybe wrong value?
We used it in place of a CHR in a dCHR-Ken70. Works fine. I am going to take the 4 we have and try them the empty Thirlmere-R we have and hopefully use them as helper woofers.
There is no Pensil cabinet for the CHS-70A yet on Frugal Phile that I can see, do you think then to try the driver in the Pensil R70.3 cabinet would likely be OK? To the untrained eye, the CHS-70A and CHR-70.3 Thiele/Small parameters look quite close... I expect there are other mysterious considerations too!
Code:
CHS-70A (Pluvia) [1] EL70 [2] CHR-70.3 [3] CHR-70 [4]
Fs(Hz) 67.863 64 65.40 70
Qes 0.695 0.66 0.69 0.84
Qms 2.391 3.23 2.66 2.83
Qts 0.538 0.55 0.55 0.65
Vas(L) 5.543 6.1 5.17 3.61
Sd(cm^2) 50.270 50.2 5.02Kmm/2 * 50
Mms(g) 3.561 3.82 4.10 4.80
Cms(m/N) 1.545 1.7 1.44 1.00
Le(uH) 35.057 251 32.44 27.442
Bl(TM) 3.968 2.85 4.20 3.064
[1] http://www.diyaudio.com/forums/twin-audio/280700-markaudio-chs-70a-extended-full-range-audio-driver.html
[2] http://www.creativesound.ca/pdf/CSS-EL70-data-080909.pdf
[3] http://www.markaudio.com/Archive/item/download/99_41ab22e79d2101506d131f937e60ae9d
[4] http://www.creativesound.ca/pdf/CHR70introduction.pdf
* Maybe wrong value?
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Good news
chrisb,
Just googled for Pensil for CHS-70, great, you're right, there is one:
Pensil S70 for Pluvia Seven/CHS-70
I don't see a link on Frugal-phile in the Mark Audio section (no mention of text 'Pluvia' or 'CHS'), and I guess an update to the complete set of plans PDF document on the site is pending too.
Thanks, that's good news.
chrisb,
Just googled for Pensil for CHS-70, great, you're right, there is one:
Pensil S70 for Pluvia Seven/CHS-70
I don't see a link on Frugal-phile in the Mark Audio section (no mention of text 'Pluvia' or 'CHS'), and I guess an update to the complete set of plans PDF document on the site is pending too.
Thanks, that's good news.
As far as i have figured CHS-70 is a Pluvia 7 sans dustcap dimple.
There is a Pensil. The S70. http://frugal-phile.com/boxlib/pensils/PensilsS70.pdf
dave
There is a Pensil. The S70. http://frugal-phile.com/boxlib/pensils/PensilsS70.pdf
dave
Pensil for Pluvia 7
Having done a bit of soul searching I decided to have a go at the Pensil for the Pluvia 7. I think this will be for my budget, and I hope the speakers will be tolerant of the location. Anyhow, I drew out the design for 18mm ply, and re-jigged it a bit. Overall internal dimensions the same of course. Main thing is was to get rid of the whole removable back panel. I think it might be more solid to do a removable cover as shown, with the main brace glued up to a solid back. Also, I don't like the idea of accurately gluing up the the cleat in the original - the design here might not look as clean but should be easier to make I think.
As you can see by the 8x4 cut sheet, there is just enough for a very small transverse brace. I don't want to use more than one sheet, for frugelness's sake. I think there's well enough space to get enough arm in there to change the amount of wadding. Any thoughts? I not wedded to the idea just yet.
Having done a bit of soul searching I decided to have a go at the Pensil for the Pluvia 7. I think this will be for my budget, and I hope the speakers will be tolerant of the location. Anyhow, I drew out the design for 18mm ply, and re-jigged it a bit. Overall internal dimensions the same of course. Main thing is was to get rid of the whole removable back panel. I think it might be more solid to do a removable cover as shown, with the main brace glued up to a solid back. Also, I don't like the idea of accurately gluing up the the cleat in the original - the design here might not look as clean but should be easier to make I think.
As you can see by the 8x4 cut sheet, there is just enough for a very small transverse brace. I don't want to use more than one sheet, for frugelness's sake. I think there's well enough space to get enough arm in there to change the amount of wadding. Any thoughts? I not wedded to the idea just yet.
Attachments
The point of the removable back on the Pensil family is to provide easy access to adjust damping fibre amounts. On the two builds in which I've participated (A7s and A12P), the final amount ending up less than starting suggestion.
As long as your access port allows for that, you should be fine. Also note, that IIRC conversations with Dave & Scott on the subject, there's no reason the port / terminus couldn't be located on the back, provided they're not immediately against the rear wall. With the sloped ceiling shown in your photos, I don't think that'd be a problem at all .
As always, take my advice with a grain of salt.
Hope you enjoy them, and find the enclosures suitable - for frugals sake.
As long as your access port allows for that, you should be fine. Also note, that IIRC conversations with Dave & Scott on the subject, there's no reason the port / terminus couldn't be located on the back, provided they're not immediately against the rear wall. With the sloped ceiling shown in your photos, I don't think that'd be a problem at all .
As always, take my advice with a grain of salt.
Hope you enjoy them, and find the enclosures suitable - for frugals sake.
Right, designed for front, but can go on the back if desired.
As Chris notes, the rear panel for the pensils was specifically intended to be removable to allow easy access for adjusting the damping quantities to suit room / amplifier / personal preference. I designed them to be easy to tune in this way (for better or worse). While it isn't mandatory, it does make adjustments a lot easier, so I'd encourage you to retain it if possible.
As Chris notes, the rear panel for the pensils was specifically intended to be removable to allow easy access for adjusting the damping quantities to suit room / amplifier / personal preference. I designed them to be easy to tune in this way (for better or worse). While it isn't mandatory, it does make adjustments a lot easier, so I'd encourage you to retain it if possible.
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