Thank you very much!

Im doing this to my hs80s. I guess that should be possible to make the limiter "switchable" with a killswitch like this?

Yes, that will work.
iz

I was wondering what JeromeMason does mean when stated "putting a stop" before the signal reaches the speakers.
Cheers, Gilberto.

Has anyone upgraded the tweeters in these things? Mine seem to have some distortion in them. I hear its is an issue with the HS80's...

absolutely NO distortion with my unmodified HS80's.

Grats!

Hi, Firstly,
Swapping relatively low impedance 4558 op-amps to OPA2132/2134 devices may not me a very good idea I.M.H.O! These have very very high input JFET devices with impedances around 10*4 or so ohms as opposed to a few k/M.ohms of both 4558 & NE5532 which are BJT op amps! These will inevitably change the characteristics of the sound not to mention some of the circuit parameters as well!

I came across this interesting article;

Working with Cranky Op-Amps

4558 is NOT a bad device for audio, but NE5532 is more musical sounding to my ears at least & have better GBW & slew rate than 4558. The only downside with 5532 is the rather high supply current which is typically 6-8mA/ device depending on the manufacturer; Intersil, Texas, Thomson etc.

I would also exercise little caution when swapping one type to an another with GBW over 25MHz, & high slew rates too! < 20 should be ok I think, as devices over BGW over 50 MHz tend to oscillate more easily than lower value op amps, especially in audio amplifiers.

I've had some bad expreiences doing this!

I find it rather strange that no one had noticed that both HS80/50 have LM3886 integrated amplifier devices in their output stages & both circuit boards seem exactly identical! This means both units actually put out 68w in 4 ohms/cab! Did I miss something here?

looking for a mod that bypasses the filters (probably keeps the high trim) and leaves only the crossover part (2 low cuts and the step filter per band. That (with High trim kept) leaves 4 ICs. OPA2134 had been done by ZenPro, Jim Williams advised LME49720 (aka LM4562). Any consensus on those ICs?
EDIT:found a LOT of positive comments about LME49860, I am tending to settle on that chip.

Can you explain how you did that ? Do I have to cut something ?
Thanks In Advance

Can you explain how to do that ?
Many ppl talk about removing the limiter on the hs80 but cant find any info on how to disable the limiter
Thanks

Try a Analog Devices ADA 4625-2 fet opamp. It's very fast, very clean, very low noise and sounds great. It's pricy. It sucks 8 ma per side. It has a metal paddle underneath. Or the BurrBrown OPA1656 fet input, similar part, much less money, slightly less noise. 100 ma output current.

It might also oscillate without further modifications to the circuit and destroy the tweeters (and even damage someone's ears)...

If somebody would put up a new pcb and component list, just for the crossover and bass boost for the woofer, no EQ filters for HS80M, I am all in.

Sorry it was 8 years ago! Back then I remember there was info on exactly what wire to snip, you may have to hunt around for it now, and maybe ask around if anything has changed in the design of the speakers. It wasn't hard to do at all, but it was high risk. I went ahead with it anyway, and the difference was pretty big.

Good luck, hopefully you can still find the info!

DGB

Damn fool question (oh, I know):

A few months back I bought some Yammys 'off the back of a truck', believing I'd lucked into a matched pair of HS8.

Wrongggg: I bought one HS8 and one HS80M.

Aside of throwing them off a bridge, is there a way to match them? As you know (and I've found out), they use different amps and the hi/mid/lo cut options are totally different...

Finally, which 4558 should be replaced on the panel. There are things that the crossover does that shouldn't be touched? Or can I easily replace all 6 pieces with 2134? that's all?

hello,
Did U made some final thougths about? I am going to update hs80m - caps purchased already but thinking about opamps - do U have any suggestions?
Thanx