[How to make the RP-160M come alive!]

On 12/9/2020 at 11:01 PM, paulgyro said:

I personally plan on using the GR Research RP-600M upgrade kit to get the most out of my 160Ms

Yeah, I also thought about it. But on the other hand I would like to fit in a much tighter budget. Currently the caps and the resistors would cost me about 20 euros + shipping ...

[How to make the RP-160M come alive!]

On 4/30/2016 at 5:53 PM, Tweaker256 said:

Thanks everyone, if you can solder it's really not that hard. You don't need to go to extremes like I did to get much better sound from the RP series of speakers. I only replace what was already there with better components.

That killer horn tweeter's crossover consisted of a 9 ohm 10 watt resistor and a 3.9 uF cap in series with the + side and a 0.36 mH inductor across the + and - in parallel, that's all.

The woofer crossover is even easer, a 1.4mH inductor in series with the + side of the woofer and a 43uF cap across the + and - in parallel.

Remove the sandcastle resistor and replace it with a 4 ohm and a 5 ohm 12 watt Mills resistors soldered in series to make a 9 ohm, you can't buy a 9 ohm Mills resistor.

Now you have many choices from easy to complete rebuild. You can remove and replace the 3.9 uF cap in the tweeter circuit or bypass it, I choose both, the easiest would be to bypass it with a 0.1 uF Audyn True Copper Cap, yes that will increase it to 4 uF but that is only a 2.58% increase still within the manufacturing tolerances. Next bypass the 43uF cap in the woofer circuit with a 0.1 uF Audyn True Cooper Cap, that is the quick and dirty approach. Bypass means solder across in parallel. You will get 95% better sound.

Replacing the 43 uF cap requires rebuilding the crossover due to its size. You need to buy a 39 uF, a 3.9 uF and a 0.1 uF cap in parallel.

You can get all the above parts from Parts Experss for about $60.00.

Hey guys, 

 

I hope you are all well.

 

I just want to bump the conversation, because I just bought a pair of RP-160m and would like to upgrade their crossovers. 

 

I have studied electronics at high school like 20 years ago, but unfortunately there is not much left in my head and therefore I will appreciate some help with the following:

 

#Objective: I would like to keep the original crossover design of the 160s and replace some of the components to improve the sound quality while following the Pareto principle. 

 

#What I will likely do:

- Replace the 9 ohm stock resistor with a Jantzen MOX 9R1 10W or Mills 9R1 12W (both have 5% tolerance which I would assume will be within the designed tolerance)

- Replace the 3.9 uF stock caps in the tweeter circuit with matching Jantzen Standard Z-Cap

- Add 0,43uF Jantzen Cross Caps in parallel to the driver circuit stock capacitor (should result in less than 1% change in capacitance, I would assume the stock electrolytic caps would be with much higher tolerance)

 

#What I would also like to do:

- Substitute the 1.4mH iron-core inductor in the driver circuit with an air-core one

 

#What help do I need:

- Feedback on replacing the stock 9 ohm resistors with 9.1 ohm resistors - would that cause any trouble?

- Feedback on adding higher quality capacitor in parallel to the electrolytic one in the driver circuit - is it going to improve sound quality given the frequency of operation (up to 1.5KHz)?

- Has anyone measured the resistance of the 1.4mH inductor in the driver circuit and what would be the impact on the crossover performance if I swap it for air-core with the same inductance value but slightly different resistance?

 

Have a great week everyone!

 

Cheers,

Momchil