Quest to be different ..A rebuild of the Quest loudspeaker.

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C.A.P

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The QUEST to be different ……A Complete Rebuild of the Quest Loudspeaker

This is the Quest speakers in my room taken this past DEC at the Michigan get together. Some of the things that made me do this were responses from comments made by my member friends.




Well after Some research and design and looking at the newer models. I decided on a few things that would benefit my Quest speakers. First was, all new Martin Logan Designs have lowered the panels. They seem to be at least 67" for the Prodigies and the Odysseys, and 60 inches for the Summits. I spoke to Jim Power, (He is as Good as a man as it gets) about this and he did say that lowering the panels does have an effect on the sound for the better. There is less ceiling bounce and it brings the ear from a seated position to the center of the panel. The second thing I was focused on was woofer blend with the panel. By opening up the grill cover and giving it a slot to breath better, it is less choked sounding. With this there was a significant improvement in mid bass. Now the Eminence driver is a funny driver that has really unique Thiele small Parameter specs. It’s a combination mid bass – sub driver. I pulled them out to inspect and see if there was anything I needed to do. I tested them with a pink noise test disc. They did not vibrate at all, or bottom out; they were in great condition, functionally and visually. Now some of you may be biting your teeth, JonFo... I know that replacing them with a newer and improved driver can be done and works well with an external X-over. I will be looking into doing this real soon but I wanted to get the best out of stock parts. The best thing about the Quest is that it can be bi amped with separate external X-over with a few wire changes already on the X-over. You can also passively Bi wire them with a switch on the back panel. I think Martin Logan had all their hats on that day !

The Construction of this can be daunting to the average individual. It is not easy just taking your speakers and start to cut the tops right off! You better have extensive knowledge in wood working with routers and chop saws and have some jig making ability. The Recovering of the woofer grill can be tricky too. The finishing can be as complicated as you make it. I went overboard with a 12 step candy red process.

First you need to lay the Quest down on its side or on its back supported with a stool or box to support the top section. I use a soft blow hammer and tap upward on the bottom of the wood rail. It will relieve the tension on the pin and grove system. Do this to both sides. Make sure to not let the panel flop out. You will then remove the panel and its 3 wires from the connector. It’s easy. There is red, black and blue. The woofer grill is held on by 4 Velcro strips, you just pull it out.

I laid the panel at the height I wanted to test it at and slid the wood rails back on (temporarily). I did some adjusting to the height several times. After listening to several musical pieces I am familiar with. I found it to be much better at all areas of sound. The bass was now free to come out in the open and not be choked by a narrow slot in the factory woofer Grill. The panel to bass driver was much better integrated. The highs were much smother and gone was the harsher sounds I was trying to eliminate. Now the hard part was going to make a new woofer grill cover that would look good and function well. As the stock cover would no longer work. It was a complete rethinking of the design of it.

The tops were cut 4 inches as you can see in the picture. I removed the top brace carefully; there are 2 brads and glue holding it down. The brads were not bad the glue joint had to be cut with a fine saw. There is a tapered pin and grove system that is used to hold the rails on that you will have to re use and router that back in the new shortened frame. There is a side 1x1 quarter round of solid maple that is the structure of the panel holding system. You will need to make a recessed cut to re fit the top support level with the top

The first picture shows the top brace removed, and cut. The second one shows a close up of the pin and metal grove system that you will re use, it also shows how much was cut off. The third shows them sitting on the cabinet with the woofer remounted. Look at the condition of those woofers. They were great.






The routing of the new grove was as simple as taking the piece of the top I cut off and lining it up with the new top. It does need to be dead on as you are putting the pins in the wood rail and they are not adjustable. I made a jig that supported the router and took a 1/2 inch plunge router and dropped it in and let her rip. The metal tapered receiver groove was screwed back in and the frame. I then took the over sized wood rail and aligned it back up with the pins and hammered it down in place. I aligned the new pin to be and marked it and installed it. I know had a longer than I needed top piece. Ill get back to that later. This was done 4 times to each frame side.

Now the real fun starts! Since the old woofer grill was only 16 inches wide and sat under the rails it was useless. Here is a picture of it lying down. That was not the original Grill cloth I recovered it once, (I hated that shiny nylon looking stuff they originally used).



The woofer Grill was a real treat to do. Not only was it much wider it had to be reshaped to match the slow curve of the panel. It also had to have supports to make a frame with out blocking the woofer. Since the Stat panel was lowered, the woofer top support was at the top of the woofer. The old top and bottom supports were made of 3/4 HDF (High density fiber board). I tore the front baffles from the woofer grill and junked the top and bottom. I made a template out of 3/4 MDF that I test fit for the shape it needed to be, so it wouldn't stick out past the Stat panel. Look at the difference in the stock bottom support and the new one. The new one is much wider and has a slowly arcing curve as opposed to the sharp edge on the factory grill. You can see the baffle test piece there too.

Now I had to use 1/2 inch 7 layered finish plywood for the top and bottom supports. I used the template to make 4 pieces with a router pattern bit. I designed a slot cut out that not only lets the woofer clear the support but breath freely. After I fitted it for rough size I glassed them all with fiberglass and resin to stiffen it up and smooth it out. The front baffles had to be re sawn to accommodate the wider grill. This was done on a table saw with a reverse angle cut. You can see in the picture, the new baffle piece on the old bottom support. You can also see the new pattern piece with the newly cut baffle piece.



After making the grill frames and gluing and sanding them down. I test mounted them for any final adjustments. I then marked the bottom 4 pin and metal tapered grove receivers’ and marked them on the new grill. You can see them in the previous pictures.

Now I moved onto the rails. As I mentioned before I did not cut them at the top as I wanted to have them dead on after I re mounted the top support rail in the new cut down panel frame. I had the pins and the rail system in check, as the new woofer grill in place, held on with the same pin and grove system,(man I love them).I marked the top of the woofer grill on the inside of the cabinet. I removed the new grill covers and I remounted the side wood rails and hammered them down in the grooves to they were set. I marked the top and bottom and cut them flush with the frame top and grill cover mark. I did this 4 times. I then took my router and a ½ inch round over bit and cleaned the newly cut edges up.

Now, you could do something as simple as painting them black or any color you like. . I went a step further, (on the recommendations of a member here). I sanded them down to bare wood, using 120 grit paper. I then sprayed a coat of black lacquer. I let that dry and re sanded that down with 180grit. This left me with a natural wood on the summer wood and a black grain on the spring wood. I then sprayed 2 coats of shellac to seal that in and at the same time, turn the natural wood a golden tone. This then was sanded with a Scotch Brite pad and coated with a light even coat of red lacquer. Since lacquer is a very reactive finish that melts into it self and any color you put down I had to seal this with 2 coats of shellac to lock the color in. After drying, I hit it with a Scotch Brite again and sprayed it down with 6 more coats of Clear Lacquer and let it dry. The fun part comes in again! Hand buffing work. I wet sanded them with a solution of soapy water and a Scotch Brite. I then used 3m buffing compound and good old elbow grease... They were each hand rubbed to a mirror shine. Look at the first picture. It shows the black grain showing through. The camera does not do them justice. You will see later in the finished pictures how they look.

Now the cabinets were also ready for paint. I wasn’t sure what to do with them. Martin Logan used a paint called Nextel that gave a really flat velvet finish. It looked good for a few years then it started to break down and get dull and sticky. This paint is thick and gooey to try and sand. Plus it has an added benefit; it is a very caustic when worked with. So to try and strip was out of the question, (this is why they discontinued using it). I found that a wipe down with 91% Isopropyl alcohol smoothed it out with out removing too much. This was done to both cabinets. I then looked for paint that I thought would cover well and hide any imperfections in the old finish. I knew a regular smooth paint was out of the question. So I looked at many textured paints and found a great paint from Rustoleum. It was an indoor out door multi colored textured paint. I did some test samples and was amazed at how well it looked and how well it covered. It looks better than the stock paint any day in my eyes. Plus I love it with my Krell Gray.

I sprayed the cabinets with 4 coats to ensure a good thick texture was on them. This was done in a few hrs as this paint can be sprayed fast. It leaves a real nice texture with a Dark gray finish with little tiny specs of light gray in it. The flash in the camera brings out a light grey color. The color on the top of the spray can is real close to the actual look. Here are the cabinets ready for the final install.

Now I was on to something at first I thought. Jim Powers at Martin Logan and I had been talking and he said he could get me some clear spar technology panels for the Quest. I ordered a set as soon as he said that. Unbeknown to him and me, they do not make them for the Quest and the bigger older units. Here is the tricky part; they do make them for smaller older units like the SL3, Arius, and such. I received my new panels and they were the new Mylar just like the ones I have but they didn’t have the clear spars. I called Jim and he did research on this and was baffled himself. He was under the impression that all replacement panels were going to be clear spar. He looked into it and came back with an answer of, “it is a matter of thickness in the stator spacers on the big Quest and Re-Quest, Monolith, and the CLS. Their supplier doesn’t have that thickness, YET!” The Good news is He is looking into this and he said “it’s not a definite NO, YET!” Since my panels are only 2 years old, they are just broken in. I will wait patiently.

I went to a good fabric store and found a great double knit fabric that was heavy and had a nice stretch to it. It had to be a heavier than average material but still breathe. I recovered the new grill with a staple gun and spray tack adhesive. If you look you can see the woofer and the opening. That is looking up from down below,(it was the only way I could get the picture, you can not ever see in there, but that is how the woofer breaths better. PS, don’t look in the corner! More on that later.



The re assembly of the panels and the new grill was a breeze. I did add new thicker weather-stripping to the frame rails. It is a 3/4x3/16 thick marine grade black Neoprene. I also added this to the bottom of the panel just like the top has from the factory. I don’t know if it is me or not, but it did seem to improve the sound in the highs. This gave a better seal for the panel to the frame and when the wood rails tightened up it has no potential for vibration or panel buzz. Here are the finished pictures of the units. I totally think they are much better looking and their function is a big benefit too.
 

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