A while ago a build the pensil R70.3 with the CHR-70. Allthough they don't sound bad the mid-tones sound overexaggerated. Nice high's, plenty low (keeping speakersize and prize in mind), the midtone seem louder loud en drown out highs and bas. It's like a wall of sound and after a while it gets tiresome. I think I do not meet the full run-in time, but i don't think it will make such a big difference. I put about the required amount of stuffing in the upperpart behind the speakers. This was my first speaker build and my knowledge of accoustic adjustment with stuffing is very little. So i'm wondering if the mid-tones can be damped with for example lining the upper part of the cabinet with felt. Any other comments are welcome of course 
I'm planning to build the Frugel-Horn in the future, can i expect a roughly simular soundstage from the Alpair 10? Mayby it's just not my taste.....
I Included some pics of the build
I'm planning to build the Frugel-Horn in the future, can i expect a roughly simular soundstage from the Alpair 10? Mayby it's just not my taste.....
I Included some pics of the build
Thank for the quick reply [emoji1303]. I think that should be to first step to go then. Any advice on what felt would work best?
Thanks for the reply Cal. I'm an ignorant newby and probably stubborn also[emoji6], but in my opinion a speaker should sound good without any tone adjustments (And again that's my opinion). The Pensils are connected to a small tubeamp with only a volume knob, so direct amplification of the source. Of course I understand that for the price of the speakers you can't expect top audiophile quality, but I like to try to get the most out of it[emoji16]. But I'm here to learn and all advise is welcome, maybe my wish is just not possible in this setup......
CHR70
Hi there Cal: "mine" = CHR70? That would make sense, increased bass response of the Frugal Horn would tend to flatten response (due to a mid range hump the OP is experiencing with the CHR70 in a Pencil enclosure). He also mentioned constructing an Alpire-10 in a FH for a future project. How does the A10 response compare to the CHR70 in a FH? ...regards, Michael
Hi there Cal: "mine" = CHR70? That would make sense, increased bass response of the Frugal Horn would tend to flatten response (due to a mid range hump the OP is experiencing with the CHR70 in a Pencil enclosure). He also mentioned constructing an Alpire-10 in a FH for a future project. How does the A10 response compare to the CHR70 in a FH? ...regards, Michael
Cotton based felt is probably the easiest to source, and could possibly be recycled. Search for 10-12mm thick.
jeff
Most people who hav ebuilt Pensils have opined that the recommended amount of stuffing is often too much. Perhaps try taking some out. And is it well teased? I also can’t but wonder if the choice of MDF instead of plywood for the build could be playing a role. Other than that looks to be a really nice build.
IMO the Alpair 10 has a better balance than CHR (all the Alpairs do) and in FHXL is superb.
dave
IMO the Alpair 10 has a better balance than CHR (all the Alpairs do) and in FHXL is superb.
dave
I assumed, perhaps wrongly, that there wasn't any stuffing. I would definitely do that as a first step.
jeff
Richard67,
Good advice already shared on the thread. Probably you can mitigate your issue with changing the amount and placement of stuffing you have in the cabinet. It will also be helpful to understand what type of material are your using as stuffing - do you have a pic? In my experience well teased out dacron type polyester fiber-fill works the best. And as Scott has already mentioned, if the stuffing is too close to the driver, that can create issues also.
Good advice already shared on the thread.
Probably you can mitigate your issue with changing the amount and placement of stuffing you have in the cabinet. It will also be helpful to understand what type of material are your using as stuffing - do you have a pic? In my experience well teased out dacron type polyester fiber-fill works the best. And as Scott has already mentioned, if the stuffing is too close to the driver, that can create issues also.Thanks for all the advices, I will start with changing the amount and placement of the stuffing. Changing amount of course is totally clear to me, but what about the placement? If i am correct the stuffing should be placed in the area behind the speaker, in this case in the upper part of the cabinet, but giving the speaker enough room and for sure not touching the speaker. Also the stuffing should be "as loose as possible" and not compressed. I hope i understand correctly... I will upload a before and after pic as soon as i get to it.
This is is the stuffing i used:
DAMPING MATERIAL | Visaton
come to think of it, the bags are 125 grams, that would mean at least 2 bags for each cabinet? Or is the 410 gramms for both cabinets together? I don't remember exactly but i think i used a maximum of 2 bags, so one bag max/cabinet. Could it be there's not enough stuffing in there? I will weigh the amount of filling to find out how much i used. I think that's the first thing to do now.......
This is is the stuffing i used:
DAMPING MATERIAL | Visaton
come to think of it, the bags are 125 grams, that would mean at least 2 bags for each cabinet? Or is the 410 gramms for both cabinets together? I don't remember exactly but i think i used a maximum of 2 bags, so one bag max/cabinet. Could it be there's not enough stuffing in there? I will weigh the amount of filling to find out how much i used. I think that's the first thing to do now.......
Hi Richard67,
Looks like you have used polyester batting style material.
My understanding is something similar to what P10 has posted here will be more suitable:
http://www.diyaudio.com/forums/plan...k-mock-assembly-instructions.html#post4344474
Looks like you have used polyester batting style material.
My understanding is something similar to what P10 has posted here will be more suitable:
http://www.diyaudio.com/forums/plan...k-mock-assembly-instructions.html#post4344474
A different CHR70 experience.
The Frugel-Horn Family
410g is per speaker. From my memory people have typically used 2/3rds that amount. You really need to tease the damping out (as in the link Zia posted). It should run from top to just above the vent.
dave
The Frugel-Horn Family
410g is per speaker. From my memory people have typically used 2/3rds that amount. You really need to tease the damping out (as in the link Zia posted). It should run from top to just above the vent.
dave
Yes, maybe that will result in different damping effects. For now I took the stuffing from both cabinets, ripped the mats apart, making the stuffing as fluffy as possible. Then I put al the stuffing in one cabinet, that would be about 375 grams. Did a test run and it seems better now. I say seems cause it's a bit difficult to get the complete picture from one speaker [emoji6].
Can anyone confirm the 410 grams of stuffing is for one cabinet?
Thank you for the confirmation Dave [emoji1303].
Since I need to buy new damping anyway, I will try to find the damping material Zman linked to, that would be more easy to tease out. I'll report back how it works out.
Acousta-stuff and Europe, not a good combination (my internet searches and other threads confirm this). Are there any europe based members who know how to get it, or know what would be suitable substitude?
Try to find Basf acoustic foam... otherwise known in supermarkets as "Magic eraser sponges" or melamine sponge.
It's white, easy to cut, and will come in different sizes, depending where you buy. Online buying in bulk is even cheaper.
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