Sibilance

[Ashmore]

It may be that I am becoming discerning, or maybe I have just become hypersensitive and preoccupied with listening for what's wrong with my equipment. Perhaps the better my kit gets the more revealing it is, or perhaps somewhere along the audio line I am introducing... sibilance.

Do you have top tips for reducing sibilance? Isolation, positioning, cables, conditioning, treatments, wear ear muffs? Muffle the tweeters? Move house and change all my equipment? What works?

[technobear]

The 1" inch dome tweeter is your sworn enemy

They can often be ameliorated somewhat by the addition of a 47 ohm tweeter damping resistor. A Mills non-inductive wirewound is perfect for the job. Just solder one across the tweeter terminals (the ones on the tweeter itself).

Cheap kit generally has worse sibilance than more expensive kit.

Cable changes can sometimes help but aren't the first port of call (IMHO).

Depends how bad it is really.

Looking at your kit list I'm surprised it's a problem. Although I haven't heard the FB1+, sibilance is not something I've particularly noticed from other PMCs including the FB1.

I don't associate it with the Sugden or the Caiman either - what mods have you done to your Caiman?

Perhaps I'm just spoiled here because the Zus are one of the least sibilant speakers I've heard.

[DSJR]

Both speakers you have tend, IMO of course, to have a bit of a "sting" in the treble that doesn't always blend with the mid quite as it should (if I've got 'em right). Pro-Acs as a breed tend to have a "saddleback" response, booming up the bass and fizzing up the treble in an attempt to artificially push the midrange (and vocals) back in a false "soundstage." OK twenty years ago perhaps, but not so much now. The PMC's can have a soft bass I found and, depending on the amp's damping factor, this can mask the midrange somewhat, allowing the tweeter to be well integrated or not, depending on this.

I know I sound like a broken record over this, but maybe it's time to listen to some better speakers from the "BBC legacy" stable, as I can guarantee that the Harbeth range will do what you now need (they LOVE the Sugden amp I'm reliably told) and the treble will be fine textured and sweet, rather than tinny and resonant. The bass of current Harbeths is under good control as well and doesn't swim around as earlier models (and classic Spendors too) could do.

As I've got older, youthful ear-abuse has come home to roost and I suffer Tinnitus which varies in its severity. At the moment, I'm ok and the system hasn't sounded better in years. Another effect of my earlier hearing abuse though is that I cannot stand any screechy midrange (or screaming twelve year olds afflicted with Tourettes') and mistracking and bad tweeters drive me insane.

I know it'll take an effort of will and possibly travel as well, but do try to get a listen to some current issue Harbeths. Even the little P3ESR will amaze you if you thought the Pro-Acs were any good. It sounds far bigger than it looks and the bass is surprisingly capable, only giving its tiny size away if hard pushed on the likes of Massive Attack. Alternative new speakers with clarity by the likes of Kudos or Neat may impress you with the sense of DEEEEETAAAIIIL, but you may find the tone assaulting if you're not careful.

P.S. I'm told the Dynaudio actives the BBC use are well behaved (can't remember the model, sorry) and sell for around £1500. Worth a listen in a pro gear shop if you can get to try them....

[Ashmore]

Thank you both for your thoughtful responses.

As you can probably see from my initial post, I am not sure how pronounced the issue is, in truth probably not much, but I have become fixated. Maybe this is my nature, or perhaps the curse of growing 'expertise' is a proportional intolerance for perceived failings.

The Caiman has murata something, rubycon somethng, elna silmic someting, WIMA somethingorother and an 826.

I am, regrettably barely up to wiring a plug let alone soldering resisters, but I appreciate the advice and may investigate.

The PMCs are lovely speakers, and the ProAcs (though I have not had them long enough to fully evaluate) gave instant gratification. But, maybe I do need to take yet another step up.

I may try to attend one of these baking days to try to weigh my perceptions against those of others.

[John]

This is one those issues that often happens when your system opens up. The main impact is likely the speakers as been suggested. Its really irrating to hear and in those days I did not have a forum of friendly faces to help me sort out
I wish you speed and not so much expensive in sorting this issue out

[technobear]

This might be a stupid question but there's just an outside chance...

You aren't using QED Silver Anniversary are you?

[Ashmore]

John - that's exactly how I feel about it. I am learning.

Thanks Technobear - ditching the QED was the first thing I did on joining the forum! Now using Van Damme 6mm pure copper.

[roob]

I have just got rid of a pair of FB1+ for a variety of reasons but one of the main problems with them for me was an increase in sibilance, in fact it was so bad that I stopped listening to certain records.
I tried different interconnects and speaker cables with no joy so I went back to my Snell J's and the problem went away. I now have Audionote J's and there is still no hint of sibilance so I would point the finger at your speakers.

[DSJR]

If the OP's location in Kent is within easy reach of the M25, then I recommend a trip anti-clockwise to the M11 and up to the Saffron Walden area, where HiFi Dave has the Harbeth range on dem, together with vast knowledge of PMC and Pro-Ac's (and others on dem). Give him a call and see if you can sort a demo out ;)

[Welder]

My apologies for being a bit off topic.

Dave R (DSJR)
I read most of what you write here Dave and I read here that you suffer from tinnitus.
I don’t know you from Adam really but I do empathise. It can be really unpleasant in its severer forms and for someone such as you who I imagine not only loves his Hi Fi but also music, it can be enormously frustrating.
I’ve lived with it for a great many years (we are probably of similar age) I’m fortunate in that mine is a single continuous very high frequency tone; and it comes and goes in intensity. I was exposed to a considerable amount of jet engine noise when I worked in avionic communications and that it seems was enough for my ears.
I realize its pointless pointing this out on a Hi Fi forum but the likelihood of many contributors here getting tinnitus in their later years is well above average, currently 1 in 5 males over 50 (non audiophiles) and rumored to be 3 in 5 for those that listen to electronically reproduced music regularly.
The truth is while audio reproduction is a wonderful hobby, it’s also likely to be damaging to your hearing. Headphones’ listening it seems has the greatest potential for permanent hearing damage as surveys suggest that many listen at decibel levels above 85db for extended periods.
I would suggest that everyone who listens to music through a Hi Fi establishes just what 85db sounds like. It really isn’t very loud. Then think about how long you listen at that volume or above.

[Jonboy]

i have buggered up my ears as well a bit using Jack hammers and petrol disc cutters without earplugs, i get some form of tinnitus sometimes now and again :steam:

[technobear]

I have just got rid of a pair of FB1+ for a variety of reasons but one of the main problems with them for me was an increase in sibilance...

I am right in recalling the main difference between the FB1 and the FB1+ was a new tweeter :scratch:

Interesting.

I've also seen the crossovers inside the PMC range and they leave a bit to be desired. White ceramic sound coffins are in abundance and could usefully be replaced with Mills Wirewounds. Some of the capacitors could be improved on too. And while you're in there, add a tweeter damping resistor (47R) because tweeter resonance is quite likely a big part of the problem here.

[roob]

I am right in recalling the main difference between the FB1 and the FB1+ was a new tweeter
That is correct, the origional metal dome was replaced with a soft dome and the crossover tweaked. I was going to have a play around with them in fact I even arranged to take them to PMC to get them checked out to see if anything was wrong but it was a 250 mile round trip and the guy I was in touch with inferred that it was the rest of my equipment not the speakers causing the problem I even swapped my amps out for a valve integrated but that did not cure it either so I decided to get rid.
Once the J's were back in the system the problem was gone

[DSJR]

I knew the metal dome original Vifa that PMC used and this was easily tamed with a better crossover, plus removing the plastic plate from the front, which made the exposed dome very easy to deform. Replacing the caps and resisotrs may well tame the excesses so worth a go.

It's been said before, but passive crossovers set right where the ear is most sensitive is a ludicrous state of affairs tbh and the phasing issues etc for an octave either side of the crossover point can have a very negative effect on the sound. Even my BC2's show their age here and what is acceptable for a 1974 speaker is totally unacceptable in 2010 - and these have good quality crossovers with carefully matched and selected components... The metal dome unit PMC used didn't like anything below 2Khz from memory and I'd have hoped the new one was better. damping it down may well cure things, but my hope is that any "air" in recorded acoustic isn't removed in the process.

[lovejoy]

How is your mains quality?

I've been having some terrible sibilance and brightness problems with my MK 1 Shahinian Arcs. Now these can be bright speakers anyway, so I was beginning to think I'd got to the end of my tether with them and needed something with a bit less bite in the top end. It wasn't until I started re-tracing my steps of what I'd changed in the system over the last few months that I realised what was going wrong.

Putting my Supra Mains Block and cables back into my system got rid of all of the sibilance and now the system is sounding excellent again, not making me want to turn it off after 10 minutes which is how it had been up until returning the Supras.

[hifi_dave]

The FB1+ sounds 'different' to the standard FB1, no better or worse, just different.

[DSJR]

The FB1+ sounds 'different' to the standard FB1, no better or worse, just different.

How tactful :D

[HighFidelityGuy]

I'd also think about getting a Gator board for your Caiman. That should smooth up the sound a bit due to it removing the opamp from the line output. For the sake of £30ish quid I'd try that before tinkering with crossovers. I'd also make sure your cables aren't to blame. Some cables I was using earlier in the year added sibilance. What interconnects (analogue and digital) are you using? :)

[Ashmore]

I'm using a digital cable that I got from Stan when I bought the Caiman. A £20 jobbie. Then running Chord (don't know the model, about £80 and they're blue) into the Caiman.

[Ashmore]

Sold the PMCs to a very nice chap from the wam. I've drafted the ProAc signatures into service on the main system till I work out what I want. Sibilance is no longer an issue.

Unfortunately I'm a bit strapped at the mo, and I don't have Harbeth/Spendor amounts of cash. Been pondering those EB Acoustics things. Ugly but well regarded it seems...

Thanks to all those who offered thoughts and suggestions on the sibilance issue.