Quad artera pop/thump

[Italian Job]

Yes, but no need to be the Lone Ranger, so long as you have a means to trigger it, or just wire a 12v battery to a suitably long cable with a switch and correct connector and you're sorted.

I'm thinking a refund is not a bad idea, and buying some other kit!

I never thought of doing that haha

 

[Italian Job]

An app that lets you remotely control not just your streamer, but *all* your devices? You know—with Wi-Fi networking and all that? Available for iOS, Android, Kindle Fire devices, Windows PCs, Macs, and Android smartwatches? And, of course, controllable via Alexa as well?
Is *that* the kind of rocket science you’re talking about

are we still talking about bare bones power amps?

 

[DavidEdwinAston]

They have cool things like remote controls and phone apps these days, as well. But maybe this is rocket science beyond Quad?

The power outlet in the wall, with it's rocker switch, remains the power outlet in the wall!
If you guys leave yours wall powered all the time, that is your business.

 

[DavidEdwinAston]

The power outlet in the wall, with it's rocker switch, remains the power outlet in the wall!
If you guys leave yours wall powered all the time, that is your business.

Anyway, we have guests who love music with us this evening, so there will be a rare turning on of the main system. I'll get my Missus to gaze meaningfully at the speaker fronts, and report any cone movement!

 

[Italian Job]

Anyway, we have guests who love music with us this evening, so there will be a rare turning on of the main system. I'll get my Missus to gaze meaningfully at the speaker fronts, and report any cone movement!

maybe make a video, secretly...

 

[Redacted]

An app that lets you remotely control not just your streamer, but *all* your devices? You know—with Wi-Fi networking and all that? Available for iOS, Android, Kindle Fire devices, Windows PCs, Macs, and Android smartwatches? And, of course, controllable via Alexa as well?
Is *that* the kind of rocket science you’re talking about?

I prefer exploding fireballs, but yeah...

 

[Randolf]

In https://pinkfishmedia.net/forum/threads/909-switch-on-thump.257267/ you can find a discussion on the thumb of a vintage Quad 909 power amplifier. In the discusion one reqports the Quad Artera having the same thumb https://pinkfishmedia.net/forum/threads/909-switch-on-thump.257267/post-4412289:

"Quad Artera power amp did the same. Made me wince to be honest, 'normal' as it was.".

I could not find the schematics of the Quad Artera, but at least the vintage Quad 909 really doesn't seem to have a relay. Since you hear a click from the relay the Artera seems to have one. If this click is really the loudspeaker terminal relay than I would say it is strange, the portection circuit of the amplifier should activate the relay only after the amplifier has fully stabalized, so there should not be a thumb. But maybe it is a different relay (from power supply?) you hear. To me this is an odd design for an expensive amplifier if really intended. Avoid a relay in the signal path or just avoid the costs for a good relay? It will not kill you speakers but would become rather annoying with high sensitivity speakers.

 

[DavidEdwinAston]

In https://pinkfishmedia.net/forum/threads/909-switch-on-thump.257267/ you can find a discussion on the thumb of a vintage Quad 909 power amplifier. In the discusion one reqports the Quad Artera having the same thumb https://pinkfishmedia.net/forum/threads/909-switch-on-thump.257267/post-4412289:

"Quad Artera power amp did the same. Made me wince to be honest, 'normal' as it was.".

I could not find the schematics of the Quad Artera, but at least the vintage Quad 909 really doesn't seem to have a relay. Since you hear a click from the relay the Artera seems to have one. If this click is really the loudspeaker terminal relay than I would say it is strange, the portection circuit of the amplifier should activate the relay only after the amplifier has fully stabalized, so there should not be a thumb. But maybe it is a different relay (from power supply?) you hear. To me this is an odd design for an expensive amplifier if really intended. Avoid a relay in the signal path or just avoid the costs for a good relay? It will not kill you speakers but would become rather annoying with high sensitivity speakers.

I think the Platinums followed the 909. Pretty much the same.e principle I guess!

 

[somebodyelse]

There's a test of output relay distortion with a nice new relay, and photos down thread of what the contacts end up looking like. In some amps the output relay is itself a point of failure after a few years. Also in that thread are some details of FET based output switching which has lower distortion and should remain that way. I'd guess the relay is for a PSU inrush limiter - a power resistor limits the initial inrush to the large toroidal transformer, then gets bypassed by a relay once the initial surge has passed. That's one method of operation anyway. I don't know whether the Artera has one - my old 520f doesn't, and doesn't have output relays. It does have a bit of turn-on thump, but quickly drops to ~1mV of DC offset. It's not as loud as loud music, so hasn't caused me to worry about any speakers I've used it with. I can see how it might be disturbing if you're used to amps that turn on silently though.

 

[Italian Job]

It will not kill you speakers but would become rather annoying with high sensitivity speakers.

I was wondering how that pop would sound on some Audio note...

I can see how it might be disturbing if you're used to amps that turn on silently though.

I don't find it to annoying with the Harbeth, I'm more worried about ruining them.

 

[DSJR]

Harbeth cones can get well exercised by plenty of kick-drum action and they seem to take it just fine if the amp isn't clipping or doing other nasty things. I appreciate the Quad engineers, when signing off the wider-bandwidth recent amps, perhaps should fit an inrush slow-start module on the power supply, but maybe they think it's not a problem. I'm convinced the ancestral 606 and 707 models didn't do this, although I don't have one to hand to confirm....

 

[Leeken]

I’ve got the immediate predecessor to the artera,the qsp.
Absolutely no pop on turning on/off unless doing it in the wrong order,but any amp can thump if turning stuff on/off incorrectly.

 

[Italian Job]

I’ve got the immediate predecessor to the artera,the qsp.
Absolutely no pop on turning on/off unless doing it in the wrong order,but any amp can thump if turning stuff on/off incorrectly.

In my case. turning the preamp first doesn't make any difference, the volume controller doesn't seem to affect it at all.

 

[Italian Job]

Harbeth cones can get well exercised by plenty of kick-drum action and they seem to take it just fine if the amp isn't clipping or doing other nasty things. I appreciate the Quad engineers, when signing off the wider-bandwidth recent amps, perhaps should fit an inrush slow-start module on the power supply, but maybe they think it's not a problem. I'm convinced the ancestral 606 and 707 models didn't do this, although I don't have one to hand to confirm....

chatgpt says otherwise, who's right who's wrong?
Yes, a short DC transient—often called an "on/off thump" or "pop"—can absolutely ruin speakers. Even though it's brief, this sudden surge of DC voltage forcefully pushes the speaker cone to its physical limit and generates extreme heat, which can instantly tear the cone or burn out the delicate voice coil.

 

[DavidEdwinAston]

Okay. Wife and I under strictly scientific conditions! (That is, no alcohol yet!)
Preamp slight tick, then settle. Monos, silent on switch on into standby condition. Then each one click, very slight hum and on in the usual few seconds. No cone movement from the LX's! Sorted.

 

[somebodyelse]

chatgpt says otherwise, who's right who's wrong?
Yes, a short DC transient—often called an "on/off thump" or "pop"—can absolutely ruin speakers. Even though it's brief, this sudden surge of DC voltage forcefully pushes the speaker cone to its physical limit and generates extreme heat, which can instantly tear the cone or burn out the delicate voice coil.

It's a matter of scale, and the shape of the pulse. It's usually significantly less than the maximum output voltage of the amp, so less than the maximum power. Unless you've overdone it with your power amp relative to your speakers this shouldn't push the woofer to its displacement or power handling limits - assuming it's just a normal power-on transient not a DC offset fault that leaves significant DC at the output all the time. For the tweeter the shape is important because the crossover will remove low frequency content anyway. A very sharp pulse might have enough energy to damage a tweeter while a slow one wouldn't - again whether you've overdone the amp relative to the speaker comes into play too. You can hear the difference, a bit like a rimshot vs. a kick drum.

Edit: Continuous DC from an amp fault is another matter entirely, constantly heating your woofer coil. You can test for that easily with a cheap multimeter, also useful for matching levels accurately. A few mV is fairly normal. 1V will put 1/8W into a woofer, so plenty of time to turn it off and get it fixed, and maybe visible as an offset from normal position. A failed output transistor could take it all the way to the power rail and quickly cook it, with your woofer cone significantly offset from normal.

 

[Chr1]

Presumably some speakers can be damaged by some amps doing this tho? I've no experience of this particular amplifier, but I have definitely heard lots of loud pops and thumps from amplifiers/speakers over the years.

Be good to know how to gauge how serious it is.
(Like, before you find out by observing no sound from a costly driver perhaps methinks!)

 

[Italian Job]

Okay. Wife and I under strictly scientific conditions! (That is, no alcohol yet!)
Preamp slight tick, then settle. Monos, silent on switch on into standby condition. Then each one click, very slight hum and on in the usual few seconds. No cone movement from the LX's! Sorted.

pre alcohol testing haha
that's really good, glad yours is behaving as it should.
Do you have the Artera monos?

 

[Italian Job]

Presumably some speakers can be damaged by some amps doing this tho? I've no experience of this particular amplifier, but I have definitely heard lots of loud pops and thumps from amplifiers/speakers over the years.

Be good to know how to gauge how serious it is.
(Like, before you find out by observing a dead driver methinks!)

I'm very intrigued to see what they come back with, for now I was only asked if that happens on both speakers

 

[DavidEdwinAston]

pre alcohol testing haha
that's really good, glad yours is behaving as it should.
Do you have the Artera monos?

No, Platinum.