Monitor 10 Rebuild with "TL" Mod

westmassguy

This project was a lot of work, but a lot of fun as well. In addition to the Crossover rebuild and modification, the cabinet was re-worked as well. Clarity ESAs were chosen for the Hi-Pass, Mills Resistors, Dayton 5% for the Lo-Pass, and Jantzen Inductors for the "TL" modification. I like using the Daytons for the Lo-Pass shunts for several reasons. Their quality is consistant, and they're relatively small compared to the Clarity PX or SA caps some others may prefer, and in my opinion, their sound is neutral when used in the shunt position. Changes required for the "TL" Mod included changing the Resistor in series with the Tweeter, and changing the Inductor located in the shunt. The resistor wasn't a problem, however the Inductor was a bit problematic. Jantzen had the exact value I needed, 0.27mh, but the DCR was slightly less than required. To compensate, I raised the value of the 2.7 ohm Resistor in series with the Inductor, to 3.0 ohms. This kept the overal resistance value of the shunt in line with the revised schematic, and would maintain the desired voicing of the new Tweeter. In addition to the other modifications, the Polyswitch was removed, and replaced with a 0.5 ohm resistor. All Resistors were relocated to the underside of the circuit board, to allow more room. A new supplimental riser board was fabricated and installed for the Clarity ESAs. New Nylon Stand-Offs were installed, and New Cardas Binding posts were added to complete the Crossover upgrade.

custopper30

Wow looks like a lot of work, but looks like it would be a great deal of fun! Good job on the rebuild!

westmassguy

The Drivers and PRs were Dynamatted, and the magnet assemblies glued. You'll note one of the drivers was replaced with a new replacement driver from Polk.

drumminman

Nice work WMG! What kind of glue did you use to prevent magnet shift? It looks white in the pics.

westmassguy

Hurricane nuts were installed for all the drivers. The cabinet was internally re-sealed with clear acrylic, and the center brace was also re-glued since there were gaps in the original hot glue Polk used. New Quartered Walnut Veneer was installed, stained and finished. The raw particle board on the back edge was sanded, sealed with lacquer, then two coats of satin black enamel applied.

westmassguy

Final assembly included reposistioning and tacking in-place the Dacron Batting.

westmassguy

After all drivers were installed, air leakage tests were done, then sweep test tones to check for resonance and rattles, and lastly, New, Acoustically Transparent, Architectural Grill Cloth was intalled. The sound from these puppies is truely amazing.

westmassguy

custopper30 wrote: »

Wow looks like a lot of work, but looks like it would be a great deal of fun! Good job on the rebuild!

Thanks, was a lot of fun

westmassguy

drumminman wrote: »

Nice work WMG! What kind of glue did you use to prevent magnet shift? It looks white in the pics.

I used the same clear acrylic adhesive, Loctite. It goes on white, but dries clear.

heiney9

Very nice work and dedication!

H9

westmassguy

heiney9 wrote: »

Very nice work and dedication!

H9

Thanks heiney9

hochpt21

Wow, nice work on those. I bet they sound sweet.

westmassguy

hochpt21 wrote: »

Wow, nice work on those. I bet they sound sweet.

Thanks, they do

Conradicles

Fantastic job!!!

westmassguy

Conradicles wrote: »

Fantastic job!!!

Thanks

jeremymarcinko

Very nice!

thsmith

Very nice ! How do they sound compared to stock ?

Thanks for sharing.

westmassguy

jeremymarcinko wrote: »

Very nice!

Thanks

westmassguy

thsmith wrote: »

Very nice ! How do they sound compared to stock ?

Thanks for sharing.

It's like night and day. Everything that's good about the 10s was retained and improved, and things that weren't so good, are now outstanding. The new Tweeters and crossover upgrades made the top end sing, and the Hurricane Nuts, Machine Screws, and Dynamatting, tightened up the bass like you can't believe.

halo71

Damn those look nice! Wish mine looked like that. So how much did it run to do this mod?

westmassguy

halo71 wrote: »

Damn those look nice! Wish mine looked like that. So how much did it run to do this mod?

Thanks halo. PM me if you'd like specifics

NJPOLKER

Very nice work. Pride of accomplishment is an awesome feeling and you sure show it with your thread/posts. Congratulations

I have to see where Feeding Hills Mass. is in relation to Charlestown RI

westmassguy

NJPOLKER wrote: »

Very nice work. Pride of accomplishment is an awesome feeling and you sure show it with your thread/posts. Congratulations

I have to see where Feeding Hills Mass. is in relation to Charlestown RI

Thanks NJPOLKER. I'm 10 minutes from Six Flags New England

[Deleted User]

Beautiful job, congratulations!

westmassguy

Kenneth Swauger wrote: »

Beautiful job, congratulations!

Thanks Ken

PolkieMan

Everything looks very professional and well done. Now they are much better than they ever were way past new.

westmassguy

PolkieMan wrote: »

Everything looks very professional and well done. Now they are much better than they ever were way past new.

Thanks PolkieMan

teekay0007

WOW, Dave! Those look fantastic, inside and out! Very nice work! Looks like you really did sweat the details. I'm guessing those are gonna be some long-term keepers. :cool:

Few questions for you:

Any sound quality difference with that one new driver?

What size H-nuts and Machine Screws (length too) did you use? Where did you get them? Any problems with the flange of the H-nut interfering with the driver baskets inside the cabinets? Did you use them on the binding post cup and tweeters also?

How did you fasten your new grille cloth to the frames? Any pointers/pics on how to make good sharp corners? Did you notice a sonic difference with this upgrade?

Did you consider re-doing the internal wiring? Any plans for that in the future?

What are you driving them with, power-wise? Are you using them in a 2-channel setup? HT?

You mention sweep test tones to check for resonance and rattles. Can you elaborate on this process a little?

Thanks for any info you can share. I'm a big, big fan of the Monitor 10 sound and have a pair that I've had since they were new and will likely be keeping them for good. :biggrin:

Lastly, I don't think you mentioned it above - and please correct me if I'm wrong - but it should probably be noted that to do the "TL" mod for these speakers, people will be using the RDO-198 tweeters and not the RDO-194 tweeters.

westmassguy

teekay0007 wrote: »

WOW, Dave! Those look fantastic, inside and out! Very nice work! Looks like you really did sweat the details.

Thanks. Too many questions for this thread. I'd be happy to answer any question directly via PM or email.
The RDO-198-1s are part of the TL Mod, that's pretty common knowledge on these forums.

PolkieMan

Oh don't thank me:cheesygrin: it's people like you that have really inspired me on this hobby.
Especially the real wood veneer that looks so much better.

westmassguy wrote: »

Thanks PolkieMan

westmassguy

PolkieMan wrote: »

Oh don't thank me:cheesygrin: it's people like you that have really inspired me on this hobby.
Especially the real wood veneer that looks so much better.

I've been veneering on and off since I was 15 or 16. It's not as difficult as you would think.