I’ve posted in Jed’s Tombstone thread how amazed I was by the Bagby/Salk design I heard at the inDIYana event last Saturday. I’ve been doing some concept design for a "value" version of this speaker and wanted to start a thread on it. I’m hoping for sensitivity in the 92db+ range, if possible. I believe Jeff said his design was about 93db.
Here is what Jeff is using in the Salk design, according to what he told us Saturday:
12” Lambda TD12H ($259ea.), crossed at around 450hz.
6.5” PHL 1070 (?) midrange ($159ea.), crossed at 2.7khz
Morel MDT33 tweeter ($149ea.)
http://www.madisound.com/catalog/product_info.php?manufacturers_id=141&products_id= 570
Jeff indicated that the PHL 1120 should work just as well, but he happened to already have a pair of the 1070’s (I think it was “1070” he mentioned, but it was definitely not the 1120)
For those who have not seen it, here is the Salk/Bagby design.
Goals:
My goals are to do a similar high sensitivity design, with open baffle mid (or perhaps open back mid as a second choice). The Salk speaker is quite large at 15” wide x 46.5” high and I would like to make a smaller front mass to the design as well (or my wife won’t let it stay in the main listening/HT room). I’m thinking a tapered design so that the mass of the speaker is lower in the box and less intrusive in the room (see mock up below). The concept design I have below has a 76L net woofer enclosure and the size is 16” wide at the bottom, with 5º tapered sides up to a width of 8.5” at the top. Of course, the baffle width on the open baffle mid will have to be sized as needed to work at the intended crossover frequency and I have not even begun to consider that. The height of the speaker is 43” and the depth is about 18” at the bottom. I envision an 8º sloped front baffle on the woofer enclosure, with a vertical open baffle on the mid/tweeter that is separated from the woofer baffle. This arrangement allows the drivers to be approximately time-aligned. I have also attached some preliminary drawings of the speaker(see the attached pdf). Depending on the tweeter chosen, I could possibly do a shallow waveguide mount for it, like I did in my Duo design and as proposed by Zaph for using the D26NC55.
Drivers:
The drivers of the Salk/Bagby design run in excess of $1100/pair, as far as I can tell. I would like to reduce that substantially, without losing too much in either sensitivity or sound quality. Here are the possible drivers I’ve come up with to consider.
Woofers:
Lambda TD12H 12”: $259
Ciare 12.00NdW1 12”: $175
Midrange:
PHL 1120 6.5”: $159
B&C 6MDN44: $120
B&C 8NDL51: $136
Tweeters:
Seas 29TFF/W (H1318), 92.5db: $44
Peerless HDS 810921, 93db: $78
Peerless DX25TG05-04, 93.5db: $28
http://www.madisound.com/catalog/product_info.php?manufacturers_id=149&products_id= 1591
http://www.madisound.com/catalog/product_info.php?manufacturers_id=143&products_id= 1744
It’s unclear on the availability of several of these drivers. I have attempted to make email contact on the Lambda and have not heard anything back. The Ciare is listed as available at Assistance Audio, but I have not confirmed that. The Peerless DX25 and HDS are listed as not in stock at Madisound, though the DX25 appears to be avaialable at PE under the old Vifa name. Below is a graph from some quick modeling in Unibox with the woofers and mids at 200w input. The Ciare is at xmax at this point and the Lambda still has a lot of room to move, however, we are at over 114db spl at this point and for HT you really need a subwoofer to handle below 40hz with either of these drivers. I’m leaning towards the Ciare since it is appears to be comparable in performance, yet would save $168. The PHL mid might be hard to beat. The B&C 8NDL51 seems to be well thought of, but I’m not sure if it can be crossed in the 2.5-2.7khz range needed to work with a dome tweeter at high spl. The 6MDN44 might work, but I have not read of anyone who has used or measured this driver. I’ve not used any of the tweeters listed, but was looking for models with relatively low distortion, but with high sensitivity and these are what I found so far that were less expensive than the Morel. If the drivers selected were the Ciare woofer, PHL mid, and Seas tweeter, the driver cost will have been reduced to about $754/pair, which is a very good savings, if SQ is not compromised to significantly.
Ok, I’ve presented my thoughts and ideas and I’d like to hear from others what they think of the concept, the drivers or others they might suggest, etc. What do you all think?
Also, does anyone have any name ideas? I thought immediately of the “PowerTowers”, but I’m ambivalent at this point.
This was edited to show the final concept version below:
Here is what Jeff is using in the Salk design, according to what he told us Saturday:
12” Lambda TD12H ($259ea.), crossed at around 450hz.
6.5” PHL 1070 (?) midrange ($159ea.), crossed at 2.7khz
Morel MDT33 tweeter ($149ea.)
http://www.madisound.com/catalog/product_info.php?manufacturers_id=141&products_id= 570
Jeff indicated that the PHL 1120 should work just as well, but he happened to already have a pair of the 1070’s (I think it was “1070” he mentioned, but it was definitely not the 1120)
For those who have not seen it, here is the Salk/Bagby design.
Goals:
My goals are to do a similar high sensitivity design, with open baffle mid (or perhaps open back mid as a second choice). The Salk speaker is quite large at 15” wide x 46.5” high and I would like to make a smaller front mass to the design as well (or my wife won’t let it stay in the main listening/HT room). I’m thinking a tapered design so that the mass of the speaker is lower in the box and less intrusive in the room (see mock up below). The concept design I have below has a 76L net woofer enclosure and the size is 16” wide at the bottom, with 5º tapered sides up to a width of 8.5” at the top. Of course, the baffle width on the open baffle mid will have to be sized as needed to work at the intended crossover frequency and I have not even begun to consider that. The height of the speaker is 43” and the depth is about 18” at the bottom. I envision an 8º sloped front baffle on the woofer enclosure, with a vertical open baffle on the mid/tweeter that is separated from the woofer baffle. This arrangement allows the drivers to be approximately time-aligned. I have also attached some preliminary drawings of the speaker(see the attached pdf). Depending on the tweeter chosen, I could possibly do a shallow waveguide mount for it, like I did in my Duo design and as proposed by Zaph for using the D26NC55.
Drivers:
The drivers of the Salk/Bagby design run in excess of $1100/pair, as far as I can tell. I would like to reduce that substantially, without losing too much in either sensitivity or sound quality. Here are the possible drivers I’ve come up with to consider.
Woofers:
Lambda TD12H 12”: $259
Ciare 12.00NdW1 12”: $175
Midrange:
PHL 1120 6.5”: $159
B&C 6MDN44: $120
B&C 8NDL51: $136
Tweeters:
Seas 29TFF/W (H1318), 92.5db: $44
Peerless HDS 810921, 93db: $78
Peerless DX25TG05-04, 93.5db: $28
http://www.madisound.com/catalog/product_info.php?manufacturers_id=149&products_id= 1591
http://www.madisound.com/catalog/product_info.php?manufacturers_id=143&products_id= 1744
It’s unclear on the availability of several of these drivers. I have attempted to make email contact on the Lambda and have not heard anything back. The Ciare is listed as available at Assistance Audio, but I have not confirmed that. The Peerless DX25 and HDS are listed as not in stock at Madisound, though the DX25 appears to be avaialable at PE under the old Vifa name. Below is a graph from some quick modeling in Unibox with the woofers and mids at 200w input. The Ciare is at xmax at this point and the Lambda still has a lot of room to move, however, we are at over 114db spl at this point and for HT you really need a subwoofer to handle below 40hz with either of these drivers. I’m leaning towards the Ciare since it is appears to be comparable in performance, yet would save $168. The PHL mid might be hard to beat. The B&C 8NDL51 seems to be well thought of, but I’m not sure if it can be crossed in the 2.5-2.7khz range needed to work with a dome tweeter at high spl. The 6MDN44 might work, but I have not read of anyone who has used or measured this driver. I’ve not used any of the tweeters listed, but was looking for models with relatively low distortion, but with high sensitivity and these are what I found so far that were less expensive than the Morel. If the drivers selected were the Ciare woofer, PHL mid, and Seas tweeter, the driver cost will have been reduced to about $754/pair, which is a very good savings, if SQ is not compromised to significantly.
Ok, I’ve presented my thoughts and ideas and I’d like to hear from others what they think of the concept, the drivers or others they might suggest, etc. What do you all think?
Also, does anyone have any name ideas? I thought immediately of the “PowerTowers”, but I’m ambivalent at this point.
This was edited to show the final concept version below:
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