Over the Christmas break I had time to open my 2.3TL?s and perform two mods I had wanted to do for some time: seal the cabinets and install Black Hole damping sheets.
The sealant I used is by Loctite and is listed as low VOC?s (< 0.5%) with no respiratory warnings on the label. It?s actually sold as construction adhesive. Can?t remember the name now, but when I get home I?ll have a look and post it. I bought three tubes at Lowes and used less than one.
Anyway the reason I did this is that with all the mods I?ve done, the speaks are a little bass shy. When doing the PR push test I had noticed that the MW?s recede to the half way point almost immediately (~ 1 sec). So I proceeded to remove all MW?s and both PR?s, and the batting, and carefully set aside the internal wiring. I had a full size caulking gun, which was tough to maneuver inside the cabinet. Where I couldn?t get it to go I used the ?ol finger method. The stuff dries clear, and has absolutely no odor! The front baffle was completely sealed with glue so I only needed to do the side panels and top and bottom caps.
Then it was on to the Black Hole. I read of TF66?s and others experience with using too much of this stuff. Apparently too much kills the sound, makes it flat and dull. I used a utility knife and heavy duty scissors to cut four 3? wide x 27? long strips, which I installed vertically on the inside back panel directly behind each bank of MW?s. Then I installed six 3.5? wide strips behind each tweeter; these were long enough to form a ?bridge? between the two verticals. It?s pretty easy to install as it has a strong PSA (pressure sensitive adhesive) that really grabbed. I did clean the back panel with a damp cloth just to be sure there wasn?t any dust or loose particles that might affect the bond. I used a little less than one sheet, which is good sense Black Hole is a little pricey, even with the 20% discount I got during Sonicraft?s sale.
Then I reinstalled the batting, reconnected all the wiring, and buttoned both speakers up. Another push test revealed a slower return to the midway point, around 2.5-3 seconds. Progress! Last night was the first time I had an opportunity to listen.
Front end includes Magnavox CDP, Peter Daniel DAC (both digital units fed by balanced power transformer), Odyssey Candela linestage w/ RCA clear tops fed by 1 KVA isolation transformer, Odyssey Stratos w/ Cap Upgrade fed by 1.5 KVA balanced power transformer, 12? sealed sub fed by 1 KVA line conditioner. Cables mostly DIY. You can see the previous mods I?ve done in my sig. Before these latest two I was very happy with the sound I was getting: nice SDA soundstage, smooth top to bottom, good transient response, good bass quality if not quantity. The latter I'm pretty sure is due to less than stellar placement, which I can?t do anything about unfortunately.
I?ll say right off that I was pretty surprised at what I heard. First I put on one of my favorites, Susan Tedeschi. This is a compilation of some of her best stuff, and most of the tunes are well recorded. Her band has both a piano and Hammond B3, background singers, a great bass player, drums, guitar. Next up was Miranda Lambert?s ?Crazy Ex-girlfriend?, then Best of Talking Heads, and finally Chicago?s debut album (still my favorite). The changes I heard were present across all these albums.
I never thought of these speakers as sounding congested, but the sound stage has opened up front to back and side to side. Each instrument is more clearly heard at its own particular volume level and in its place. It?s fascinating on the ST album to hear the organ move to the front playing lead or heavy rhythm, and recede to the background playing flourishes. Transients are improved with ride cymbals a little easier to hear. Female vocals sound a little more natural; a little chestiness I hadn?t noticed before is gone. The speakers, while sounding smoother also have more slam, more dynamic punch. I haven?t noticed a change in bass output. It does a fine job until that point, but the speaks are rated for 750 wpc, and it?s somewhere around 150-180 wpc. Now what I?m thinking is that the sound wave from the MW?s was bouncing off the back wall (before BH) and returning to hit the rear of the cones causing breakup and loss of clarity. I never thought the 2.3TL's lacked any of the qualities I heard last night, they are now enhanced.
I?m running out of descriptions here, but to sum it up I would say the BH is absolutely worthwhile. Sealing the cabs, don?t know since I did both of these together. I would rank this as one of the top tweaks I?ve performed on the speakers, especially for the cost.