Technics SB-5 capacitors

[eriksquires]

I"d always replace electrolytic with films, but the ESR will affect the crossover. I would suggest you replace the smallest caps with film. Mundorf MKP is a good, cheap starting point.


Measure the ESR first, you can do this with Dayton DATS easily, or build a rig for Room EQ Wizard (search impedance measurement). If you replace a cap with > 0.5 Ohms in ESR you'll probably want to compensate for it when switching to film.

 

[krivium]

Erik,
This is exactly why i used 'upgrade' in my previous post. I faced that issue with mkp i tried for my own SB-M2.
And this didn't comes cheap as the values used in my xover were all >5uf.

Had same problem some month ago with a Wharfedale TSR 112 which had been 'upgraded' by someone else : sound was overlybright. Reverting to Mundorf bipolar Ecap made results more coherent though less 'accurate'.
Owner found them more to it's liking once reverted to bipolar ( and once volume potentiometer bypassed).

 

[Detectit1]

Thanks all for your input.

The bolts are indeed brass and not steel.

My pot meters for mid and highs section were sounding scratchy too. I disassembled them and cleaned them out.

It's a big curled wire. As I thought the sound it made when turning was a very dry carbon path. So it's normal.

I really like the possibility to adjust sound that way because the treble and bass knobs on the amp is so so.

I did short cut the breaker circuit. The resistance was not that great 0.30 Ohm. But already read somewhere it's better.

So I desoldered the Caps. And these are the conclusions.

3.3 uF 50V now rated 5.1uF
8.2 uF 50V now rated 9.5uF
12 uF 50V now rated 15uF
15 uF 50V now rated 18.1uF

So quite some differences allthough not shocking overall it shows me i want to replace the caps.

I am not that technical experienced in the differences and characteristics of Electro hardware. Film caps, oil caps, paper wrapped etc.

I just want to get close, or bit better than original.

Tried too look op datasheet of the caps bu t no

Type number ece 050Y8R2K 8.2 uF for instance.
View attachment 828849 View attachment 828850

 

[wiseoldtech]

Thanks all for your input.

The bolts are indeed brass and not steel.

My pot meters for mid and highs section were sounding scratchy too. I disassembled them and cleaned them out.

It's a big curled wire. As I thought the sound it made when turning was a very dry carbon path. So it's normal.

I really like the possibility to adjust sound that way because the treble and bass knobs on the amp is so so.

I did short cut the breaker circuit. The resistance was not that great 0.30 Ohm. But already read somewhere it's better.

So I desoldered the Caps. And these are the conclusions.

3.3 uF 50V now rated 5.1uF
8.2 uF 50V now rated 9.5uF
12 uF 50V now rated 15uF
15 uF 50V now rated 18.1uF

So quite some differences allthough not shocking overall it shows me i want to replace the caps.

I am not that technical experienced in the differences and characteristics of Electro hardware. Film caps, oil caps, paper wrapped etc.

I just want to get close, or bit better than original.

Tried too look op datasheet of the caps bu t no

Type number ece 050Y8R2K 8.2 uF for instance.
View attachment 828849 View attachment 828850

As I mentioned previously, Technics uses brass bolts.


As for the slight difference in cap values - they are normal, within range, and would not be detectable with normal ears.
Besides, cap values have a tolerence of + - percentage.
If it were me, I'd leave them alone.