ADS L810 crossover upgrade

[ptempel]

Am thinking of using the following parts to build a new crossover for these speakers. The schematic and parts list is here:

http://sportsbil.com/ads/xoverschematic.pdf

The 3-way on page 2 matches the parts I found. Let me know any changes you would recommend. The original resistor for the midrange is 4.7 ohm. Is 4.5 ohm close enough for it? Also will need to unwind the 2.7mH inductor to get 2.6mH. Let me know how to measure that with a DVM.

Thanks,
Philippe

2.5mH 18 AWG Air Core Inductor Jantzen Parts Express 255-270 2 $30.24
0.5mH 18 AWG Air Core Inductor Jantzen Parts Express 255-230 2 $13.26
2.7mH 18 AWG Air Core Inductor Jantzen Parts Express 255-272 2 $31.44 Unwind to get 2.6mH
0.18mH 18 AWG Air Core Inductor Jantzen Parts Express 255-208 2 $9.16

100uF 100V non-polar electrolytic Jantzen Parts Express 027-360 2 $4.14
4.7uF 400V Z-Standard Capacitor Jantzen Parts Express 027-274 2 $7.72
10uF 800V Z-Superior Capacitor Jantzen Parts Express 027-497 2 $90.58
6.8uF 800V Z-Silver Capacitor Jantzen Parts Express 027-784 2 $69.82

1.5 Ohm 12W Non-Inductive Resistor Mills Parts Express 005-1.5 2 $8.50
4.5 Ohm 12W Non-Inductive Resistor Mills Parts Express 005-4.5 2 $8.50 Okay to sub 4.5 for 4.7 ohm?

Crossover PC Board 3-Way 12 dB Large 5" x 9" Parts Express Parts Express 260-134 2 $11.60

$284.96 TOTAL

[ptempel]

Replaced the 4.5 ohm resistor with a 3.5 ohm and 1.2 ohm in series to get 4.7 ohm total.

3.5 Ohm 12W Non-Inductive Resistor Mills Parts Express 005-3.5 2 $8.50 connect in series with 1.2 ohm to get 4.7 ohm
1.2 Ohm 12W Non-Inductive Resistor Mills Parts Express 005-1.2 2 $8.50 connect in series with 3.5 ohm to get 4.7 ohm

[ptempel]

The parts seem a bit cheaper at Madisound. They also have the 4.7 ohm resistor. So I redid the parts list (see below). Will call them to see if they can customize the 2.6mH and 0.18mH inductors. From what I've read, most folks try to use the best cap for the midrange. But the 10uF ClarityCap MR is $123.30 which seems to be over the top. So I stayed with SA for this one.

2.5mH 19 AWG Air Core Madisound Madisound 2.5mhl 2 $22.40
0.5mH 19 AWG Air Core Madisound Madisound .5mhl 2 $9.60
2.75mH 19 AWG Air Core Madisound Madisound 2.75mhl 2 $23.20 Unwind to get 2.6mH
0.2mH 19 AWG Air Core Madisound Madisound .2mhl 2 $5.60 Unwind to get 0.18mH

100uF 400V Solen Fast Cap Solen Madisound cp100 2 $58.20
4.7uF 250V ClarityCap PX ClarityCap Madisound px4.7 2 $10.50
10uF 630V ClarityCap SA ClarityCap Madisound sa10 2 $35.50
6.8uF 630V ClarityCap SA ClarityCap Madisound sa6.8 2 $27.70

1.5 ohm 10W Metal Oxide Film Mundorf Madisound mox1.5 2 $5.00
4.7 ohm 10W Metal Oxide Film Mundorf Madisound mox4.7 2 $5.00

$202.70 TOTAL

[speaker dave]

A lot of cost. A lot of time.

What do you really expect to pick up?

Be aware that designers pick crossover components with regard to all their parameters. Inductors are chosen to have the right resistance rather than the lowest resistance possible. Some time capacitors are chosen in the same way (ESR).

David S.

[ptempel]

Originally Posted by speaker dave

A lot of cost. A lot of time.

What do you really expect to pick up?

Be aware that designers pick crossover components with regard to all their parameters. Inductors are chosen to have the right resistance rather than the lowest resistance possible. Some time capacitors are chosen in the same way (ESR).

David S.

Thanks David. Was hoping to get a little more clarity and soundstage with the upgrade. I did a similar upgrade with some Polk monitor 5B 2-way speakers and noticed this difference. However the cap and resistor upgrade for them was smaller than upgrading the tweeters, IMO. Have talked to Brian at Madisound and he recommended that I at least keep the L3 and L4 midrange and tweeter inductors. He mentioned that the wire thickness on them was critical besides the value. So I can save some money by keeping them and perhaps the other two. This brings my list down to:

100uF 400V Solen Fast Cap Solen Madisound cp100 2 $58.20
4.7uF 250V ClarityCap PX ClarityCap Madisound px4.7 2 $10.50
10uF 630V ClarityCap SA ClarityCap Madisound sa10 2 $35.50
6.8uF 630V ClarityCap SA ClarityCap Madisound sa6.8 2 $27.70

1.5 ohm 10W Metal Oxide Film Mundorf Madisound mox1.5 2 $5.00
4.7 ohm 10W Metal Oxide Film Mundorf Madisound mox4.7 2 $5.00

0.01uF bypass cap Vishay/Roderstein Mouser 75-MKP1837410161F 4 $5.28 use for midrange (10uF) and tweeter (6.8uF) caps

$147.18 TOTAL

I added the MKP1837 bypass caps to help take away some "grainy edge". Have read about it here:

Humble Homemade Hifi

(scroll down toward the bottom under "Vishay MKP1837" section). They're cheap and since I'm there I might as well give them a go.