Improvements To Modified SDA SRS 1.2TL Crossover

thejck

what guage wires and connectors are you guys using for the 10 guage inductors to connect to the board?

evhudsons

Same question for the 14 gauge. I just got my Solen's in today.

evhudsons

Even with all the comments about it, they are surprisingly heavy. Wow.

thejck

haha dude if you think the 14 guage are heavy..
the 10 guage are as big as a dinner plate

evhudsons

Hehehe, if yours is as big as a dinner plate it must be as heavy as my dishwasher.

thejck

wife had to call me out from the door to come grab them from the ups guy cause she could not hold on to it.

JayCee

Parts Connexion has a store-wide 20% off sale. They gave me the discount on the Solen 10 gauge inductors...total, shipped to Texas, is $385.85 (US). Said it'd take a couple of weeks to fill the special order and then send them my way.

Toolfan66

I pulled my inductors out and made some 2.5ft leads out of some audioquest type4, and mounted these badboys to the floor of my 1.2tl's. I was concerned about changing the inductance some but I could always put it back the way it was.

The reason I wanted to do this is it seemed my speakers felt a little bloated once in awhile. it's funny as it would sound fantastic one day then the next it just didn't feel right, so I started wondering if the inductor as big as it is and being so close to the internal wiring and the crossover board was the problem? I also wondered if this is normal during break/burn-in time? not sure about any of it all I know is it just started doing it about 2 weeks ago and was bugging the hell out of me..

Right now all sounds great, and I will update if this continues or if it fixed my problem. If this corrects the issue I am thinking I will get some 9ga Kimber Kable from Gold Sound here in town a little pricey but what the hell..

evhudsons

I have to recreate dk's mounting of the Solen's, but what would happen if I mounted them to the bottom of the crs and used a heavy gauge wire to connect them to the crossover. Heavy as heck inductors!

evhudsons

I noticed the same change in quality too but found my source material to be the issue. I usually either use streaming or pandora but the fluctuations of the Internet caused the variance. I used my cd player and it is constant. So when I thought it was my speaker or connection, playing a certain cd for consistency showed me that the speaker and connections are fine. It's a great feeling to discover that hardware is fine.

drumminman

In my 2.3TL's I mounted them to the floor on the left side (if looking at the speaker from the front) with the hole facing up. My crossovers are on the other side (not the stock placement). I know you don't have nearly as much space, but this orientation/placement may still produce minimal interaction.

thejck

i like the idea of mounting them on the floor..since the damn things are so heavy. Did you glue them down?
I found a couple of 10 guage disconnects at the HD. One is a spade type and the other is a hollow circular type. Does it matter what i choose?

drumminman

thejck wrote: »

i like the idea of mounting them on the floor..since the damn things are so heavy. Did you glue them down?

I found a couple of 10 gauge disconnects at the HD. One is a spade type and the other is a hollow circular type. Does it matter what i choose?

The quote below is from a post I made after I installed them. The whole post can be found here: http://www.polkaudio.com/forums/showthread.php?123728-Review-of-New-Solen-inductors-in-2.3TL-s


"Since everything sounded so good and met my expectations I decided to go ahead and mount the Solens to the floor. I couldn't find any bolts that were non ferrous so I came up with a different solution.

I cut 4 "feet" per cabinet, 1" x 3" each out of 1/2" plywood, and glued and screwed them to the floor with JB Weld and 1" #10 brass screws. I used the screws to both clamp the feet while the glue set and to provide a little extra insurance. Next I cut platforms out of 1/4" plywood a little larger than the inductors. Using the same brass screws I fastened the shelf to the feet, without glue. That way if I ever need to remove the inductors the only thing permanently attached is the feet. I used 4 large nylon locking ties to fasten each inductor to its shelf through holes drilled into the shelf, each tie rated at 175lbs. They ain't going nowhere and the nylon ties won't change the measured performance of the inductors."

If I had a working camera I'd take pictures. Hope you get the idea from the description.

evhudsons

Thanks! I think I've got the idea. I have some plywood and that makes sense

Toolfan66

hahaha!!! Well I found my problem, when I tore down my rack to put up my new one I didn't double check the settings on the impedance switches on my MIT shotgun IC's needless to say they were all over the place..

much much better!!!

F1nut

evhudsons wrote: »

I have to recreate dk's mounting of the Solen's, but what would happen if I mounted them to the bottom of the crs and used a heavy gauge wire to connect them to the crossover. Heavy as heck inductors!

Mounting a large inductor inside the cabinet of a CRS+/4.1TL is not a good idea as it will reduce the already small cabinet volume.

Toolfan66

If I'm not nistaken DK used the northcreeks in his CRS+/4.1TL...

DarqueKnight

TOOLFORLIFEFAN wrote: »

If I'm not nistaken DK used the northcreeks in his CRS+/4.1TL...

You are not mistaken. I used 14 gauge 16 mH Northcreek inductors in two pairs of my CRS+'s and a 14 gauge Solen inductor in the third pair. I discussed the inductor upgrades here:

CRS+ (1989-Version) PCB Xover and SDA Inductor Upgrade

F1nut wrote: »

Mounting a large inductor inside the cabinet of a CRS+/4.1TL is not a good idea as it will reduce the already small cabinet volume.

Installing the larger Solen and Northcreek inductors resulted in a less than 1% reduction in interior volume of the CRS+ cabinet.

The interior volume of a CRS+ cabinet is 8" x 11" x 18.5" = 1,628 cubic inches.

The stock 16 mH 18 gauge inductor is 4" in diameter by 2.125" high. The volume of the stock 16 mH inductor is V= pi x r^2 x h = 3.1415 x 4 x 2.125 = 26.7 cubic inches.

The 14 gauge Solen and Northcreek inductors are 6" in diameter by 1.5 inches high. The volume of the Solen and Northcreek 16 mH inductors is V= pi x r^2 x h = 3.1415 x 9 x 1.5 = 42.41 cubic inches.

The Solen and Northcreek inductors represent an inductor volume increase of 42.41-26.7 = 15.71 cubic inches. This equates to a CRS+ interior cabinet volume decrease of:

15.71 cu. in./1,628 cu. in. = 0.009 or 0.9%.

My modification report discusses subjective listening evaluations and provides pre and post mod response measurements. I found that the Northcreek inductors were a fantastic improvement over the stock inductors. The Solen inductors outperformed the Northcreek inductors and cost half as much.

Toolfan66

I have yet to put my Northcreeks in my CRS+'s But I also have a set of 3.1's that I have been wanting to dig into as well, I have thought about just selling them too as if I really need another set of modded SDA's.. lol.

F1nut

The Solen and Northcreek inductors represent an inductor volume increase of 42.41-26.7 = 15.71 cubic inches. This equates to a CRS+ interior cabinet volume decrease of:

15.71 cu. in./1,628 cu. in. = 0.009 or 0.9%.

Eh, I can't argue with that info.......still don't like the idea tho.

evhudsons

Would putting in norez also have some affect on reducing the volume of the enclosure? I'm assuming that in these upgrade tweaks the performance increase is worth losing some enclosure volume. I will put in my solens and see....

drumminman

evhudsons wrote: »

Would putting in norez also have some affect on reducing the volume of the enclosure? I'm assuming that in these upgrade tweaks the performance increase is worth losing some enclosure volume. I will put in my solens and see....

\

Be careful about using too much damping on the cabinet walls. It can kill the sound.

Don't remember if it was No Rez, but some of the regulars here covered sidewalls and back wall with some type of speaker cabinet damping and felt like it was overkill. They removed all but the stuff on the back wall (these were large speakers, e.g. 1.2 TL etc.) and thought it sounded much better.

Good luck!

evhudsons

drumminman wrote: »

\

Be careful about using too much damping on the cabinet walls. It can kill the sound.

Don't remember if it was No Rez, but some of the regulars here covered sidewalls and back wall with some type of speaker cabinet damping and felt like it was overkill. They removed all but the stuff on the back wall (these were large speakers, e.g. 1.2 TL etc.) and thought it sounded much better.

Good luck!

I read that too, I think it was "blackhole" or something like that. I only had a little bit of no rez that Trey had left over I got for a couple of bucks so there isn't much in there. I took it and made four pieces per speaker, and then put on partial piece on the cabinet sides and top.

drumminman

evhudsons wrote: »

I read that too, I think it was "blackhole" or something like that. I only had a little bit of no rez that Trey had left over I got for a couple of bucks so there isn't much in there. I took it and made four pieces per speaker, and then put on partial piece on the cabinet sides and top.

How do you like the sound with it in place? I've thought about getting something for the back wall of my 2.3TL's.

Toolfan66

Three inch strips long enough for the length of the drivers is plenty, anything more is overkill..

thejck

DarqueKnight wrote: »

My Parasound JC 1's run 10 degrees hotter after the inductor mod when playing music at moderately loud (90 dB-C) levels.

I noticed something that I could not figure out today.

I have the HCA-3500 and today i got the left speaker setup with the new 10ga inductor. while the right still has the stock inductor.
After about an hour of use the amp is hotter on the right had side.. does this make sense?

DarqueKnight

It does if the right side was running much hotter to begin with. Do you know for sure that it wasn't? The bias in one (or both) channels may have gone out of spec and need to be adjusted. This is an easy adjustment to make. Unfortunately, Parasound does not sell service manuals to consumers. You would need to have this checked by a service center or dig up a service manual somewhere on the web.

thejck

I found the specs on the amp and a you tube video on how to do it. Thanks for the heads up
http://www.youtube.com/watch?v=HR2DsmnAG1k

I might end up having to take it someplace anyway... I am not sure how I can get a 1khz sine wave on the input

Model Number Heatsink Temperature Bias Voltage Tolerance
HCA-3500 40-45 C 22 mV +/- 2 mV

The bias tracking circuit of the HCA-3500 requires being set with no signal applied and again with a signal
applied. When the HCA-3500 has an input signal connected, The bias rises to its high level setting.

1.Connect a DV voltmeter (in the millivolt range) across any of the emitter resistors.
2. With no signal applied, adjust TVR 1 until the bias level is 3 mV +/- 1 mV
3.Apply a 1 kHz sine wave to both inputs of the HCA-3500 Do not connect a load to the output.
4.Adjust TVR 3 until the bias level is 20 mV +/- 2 mV.
5. Confirm that the bias has remained at 20 mV +/- 2 mV.

DarqueKnight

thejck wrote: »

I found the specs on the amp and a you tube video on how to do it. Thanks for the heads up
http://www.youtube.com/watch?v=HR2DsmnAG1k

I might end up having to take it someplace anyway... I am not sure how I can get a 1khz sine wave on the input

Model Number Heatsink Temperature Bias Voltage Tolerance
HCA-3500 40-45 C 22 mV +/- 2 mV

The bias tracking circuit of the HCA-3500 requires being set with no signal applied and again with a signal
applied. When the HCA-3500 has an input signal connected, The bias rises to its high level setting.

1.Connect a DV voltmeter (in the millivolt range) across any of the emitter resistors.
2. With no signal applied, adjust TVR 1 until the bias level is 3 mV +/- 1 mV
3.Apply a 1 kHz sine wave to both inputs of the HCA-3500 Do not connect a load to the output.
4.Adjust TVR 3 until the bias level is 20 mV +/- 2 mV.
5. Confirm that the bias has remained at 20 mV +/- 2 mV.

It's good to know that Parasound is no longer being secretive about their amp adjustment procedures.

Use a test signal CD to generate a 1 kHz signal. I use the 1 kHz tone on track 1 of the Autosound 2000 Test CD #101:

Autosound 200 Test CD #101 at Crutchfield.com.

Set your CD player on "repeat track". Pay attention to when the track is nearing the end because you don't want the signal to switch back to the beginning while you are in the middle of an adjustment.

thejck

sweet thanks