Build of gr-research X-LS Encore

[Rick Sykora]

Amir tells me he has plenty to test so no need to hurry...

My router is not as much dead as dying. It is slipping and will not cut at a specific depth, so cannot route the tweeter recess reliably. For a while it was useful as it would slip enough with each rotation to be somewhat usable. Now it is so weak that it slips in large increments! Amazon indicates my nice new one should arrive in about a week. I could fully assemble the box and finish the routing on the box, but since there is no rush, would rather do the job as I would normally.

So, this thread will take a brief respite and return after the holiday. Enjoy yours and hope to be back as soon as possible!

Be safe out there and keep cool!

 

[jhaider]

I'm not a big fan of fiber glass or polyfill with ported speakers. It can break down and be spat out of the port.

Try recycled denim insulation.

 

[Laserjock]

Appreciate the work and build.

Are there any commercially available speakers that do not have any damping material installed?


For the car analogy, I’m thinking it’s like getting a tire without air installed?

 

[peanuts]

fwiw every speaker iv built sounded like shit without dampening material.

 

[Rick Sykora]

Appreciate the work and build.

Are there any commercially available speakers that do not have any damping material installed?


For the car analogy, I’m thinking it’s like getting a tire without air installed?

In my experience, most have some fiber fill of some sort. Have not seen many with dampening sheets or foam lining (aside from higher-end ones).

However, since you mentioned cars, have seen many car situation without fiber fill. As stock automotive designs go, would hardly consider them best in class audio though. My most recent experience was my daughter's 2014 Mazda 6 front door speaker and they had none. I used to have a 2013 Honda Accord V6 and know the rear deck speakers did not have any. My father's 2010 Lexus ES fronts did not have any either.

For the record, if they were my speakers, I would (at least) have foam lining and perhaps some fiber fill. For a $275/pair of DIY speakers, am open to a science experiment to see what results we get without any. As I build the cabinet and look to where you might put No-Rez, there are not many open surfaces. The top and the left side are candidates, but everywhere else has parts. Maybe that is why the speaker webpage only states "You might also want to add a sheet of No Rez. "

 

[Laserjock]

In my experience, most have some fiber fill of some sort. Have not seen many with dampening sheets or foam lining (aside from higher-end ones).

However, since you mentioned cars, have seen many car situation without fiber fill. As stock automotive designs go, would hardly consider them best in class audio. My most recent experience was my daughter's 2014 Mazda 6 front door speaker and they had none. I used to have a 2013 Honda Accord V6 and know the rear deck speakers did not have any. My father's 2010 Lexus ES did not have any either.

For the record, if they were my speakers, I would (at least) have foam lining and perhaps some fiber fill. For a $275/pair of DIY speakers, am open to a science experiment to see what results we get without any. As I build the cabinet and look to where you might put No-Rez, there are not many open surfaces. The top and the left side are candidates, but everywhere else has parts. Maybe that is why the speaker webpage only states "You might also want to add a sheet of No Rez. "

Sounds good.
No damping seemed to set them up for failure but it’s a good experiment if you feel like opening it up and adding later etc.

My car analogy was about tires coming without air in them which I’m not sure of it translates as well since I don’t know if damping is “requirement” to make a speaker work correctly or not.

That got me to thinking. Hmmm, would an “air bladder” of some sort with an external valve stem that you could add or subtract air in, make a good “tunable” cabinet?

 

[Rick Sykora]

Just a quick update as I know many are interested in seeing this speaker tested. My new router is scheduled to arrive tomorrow. The missing capacitor is not as clear. Checked with GR and got a "caps are in the mail" response, so should be soon. The crossover board has been cluttering my keyboard drawer for over a week now. If I did not have equipment issues slowing the build, would have ordered them from PE and had them the next day. Not sure why GR cannot get 1 uF poly caps shipped more promptly .

 

[Rick Sykora]

Sounds good.
No damping seemed to set them up for failure but it’s a good experiment if you feel like opening it up and adding later etc.

My car analogy was about tires coming without air in them which I’m not sure of it translates as well since I don’t know if damping is “requirement” to make a speaker work correctly or not.

That got me to thinking. Hmmm, would an “air bladder” of some sort with an external valve stem that you could add or subtract air in, make a good “tunable” cabinet?

Am usually opening the speaker up multiple times throughout the build and acceptance testing. Access in some is easier than others, but this is a smallish 2-way with a sizable woofer cutout and so access is not much of an issue.

As for the air bladder, the tough part would be sealing the area around the valve (particularly as it would need to handle multiple cycles of expansion and contraction). Most of the time, the major tuning is done is Bassbox or other comparable box design software. If I am dealing with trying to retrofit a woofer into an existing cabinet, I might use a bag of sand or glass beads to test a reduction in cabinet volume, but as I mentioned, can do most of the design work in Bassbox. So, at least as a design aid, your air bladder idea may have some merit, just not as much as with sim software these days.

I mentioned how the sealing the valve might be tricky, and I used to think that small leaks did not matter all that much. With more experience, I have seen how much difference a small leak can make. Even recently, as I worked on adding damping to the Integrity speaker, I did not fully tighten a screw on the passive radiator. I went to measure the system impedance and the box tuning impedance rose dramatically. I had not seen this before and lacking much PR experience, thought the damping had caused. When I went to remove the PR for troubleshooting, I noticed the loose screw and tightened it up. All was well again.

 

[Rick Sykora]

Missing capacitors arrived today. Will finish crossover boards for first speaker tonight!

 

[Rick Sykora]

...and here they are...

 

[Rick Sykora]

Well my new router arrived. It is a beast. Is about twice as heavy as my old router! But now I have a variable speed with soft start and can use 1/2 inch bits too. Need a day or so to do some practice cuts and get used to it. This time of year would normally be outside, but a bit too steamy to be working outside with power tools today.

It also came with a dust collector which should make my wife happier and allow me to use it indoors more often.

Stay tuned and will do my best to crank out some baffles soon.

 

[Rick Sykora]

Since my old jig did not fit the new router, bought a Jasper jig and installed it. Routed the tweeter hole using a 3/8" bit to cut the recess at a depth of 3/16", then cut the main hole with a 3.125" hole saw and use router to carve out the spacing for the tweeter's terminals. I use hole saws when I can as they create less dust and do not require multiple passes (as hole cutting with the router would). I will then turn over the front baffle and cut the 5.75" hole for the woofer.

After that, will change bits and do the specified round-over for the woofer cutout...

Finally, need to cut holes on back baffle for port and terminal cup, like so...

After some lunch, back to assembling the completed kit.

 

[amirm]

Well my new router arrived.

Ah, I bought the original Dewalt version in Gray (before Black and Decker bought them) some 30 years ago. It is a great router but the springs in it are very strong so hard to plunge.

 

[Rick Sykora]

Ah, I bought the original Dewalt version in Gray (before Black and Decker bought them) some 30 years ago. It is a great router but the springs in it are very strong so hard to plunge.

My previous routers were handed down and frankly seem primitive in comparison now. Should have done this sooner for $205! Get what you say about the plunge but shortened the travel and, if the springs don’t loosen, will have to get stronger.

 

[amirm]

I never got stronger so I took out one of the springs. It made a bit too loose but at least I could plunge it and not risk having it slip off.

 

[Rick Sykora]

Before my router distraction, had glued a side to the the top, so we pick up from there. I realized after deciding mounting spots for crossovers, it would be best that these initial parts are the bottom and the right side. So best to drill mounting holes for the crossovers now. Woofer crossover on bottom and towards cabinet back...

flipping the cabinet on the one side, will mount the tweeter crossover along the bottom right towards cabinet back too...

Here is where I made a bit of an error. Am used to mounting front baffles last, but due to unique bracing, this is best done last. Next, you should attach the other side and the center brace as this makes the gluing simpler. I was hurrying and so forgot a pic here, so here I have attached both the top, the center brace and the other side:

 

[KaiserSoze]

So much fun to be had.

"Driver burn in facts ... The greatest amount of change in the sound of a speaker can be from the electrical burn in. A majority of this is from capacitors, but some of the electrical burn in has to do with the wire, and voice coils of the drivers."

"Another upgrade to the Encore version was to by-pass all of the poly caps in the tweeter circuit with Gen.1 Sonicap by-pass caps. This further increased detail levels and allowed for a more distinct space between the notes as the fast discharge by-pass caps help reduce smearing."

http://gr-research.com/cables.aspx

 

[Rick Sykora]

Am finishing the bracing and prepping to wire the crossovers. Was surprised to find the supplied wire is solid core with a hard vinyl jacket. Maybe this is why there is shrink wrap supplied too? Looked at his crossover posting and looks as though he only uses shrink wrap to insulate anywhere he makes an external wiring connection to the crossover. Given exposed point to point wiring everywhere, not clear what benefit is being achieved. Since the solid core will pull harder on the board connections as drivers are wired and mounted, is more beneficial to tie down those connections in my opinion.

I had thought he might use the shrink wrap to dampen the hard wire jacket for the driver wiring where it might contact hard surfaces inside the cabinet. However, no indication of this from GR, so will use my best judgement. Finally, as for bypass caps, there is only one used in the base crossover. There is only one other cap in the signal path, to bypass it alone cannot seem to justify the $105 up charge, so guessing they must upgrade all the caps?

 

[raindance]

So much fun to be had.

"Driver burn in facts ... The greatest amount of change in the sound of a speaker can be from the electrical burn in. A majority of this is from capacitors, but some of the electrical burn in has to do with the wire, and voice coils of the drivers."

"Another upgrade to the Encore version was to by-pass all of the poly caps in the tweeter circuit with Gen.1 Sonicap by-pass caps. This further increased detail levels and allowed for a more distinct space between the notes as the fast discharge by-pass caps help reduce smearing."

http://gr-research.com/cables.aspx

What utter BS.

 

[Rick Sykora]

With the front baffle now glued on...

added the front braces with the prescribed Liquid Nails adhesive...

After a bit of time for the front ones to set, added the top ones too...