New system up and running

So, the corner shelves are up and the bigger of the two is taking the weight of the eVo2 without complaint.

The Quad 99 CD-P is still running in but sounding sweet - and what a nice looking little player it is too.

Anyway, all connected up, fired it up (annoying pop through the speakers every time the amp is switched on) and what a lovely, smooth but detailed sound I'm getting - the word 'analogue' keeps springing to mind.

Bass from the Harbeths good but there was something a little flat earth about the whole thing - great overall sound but not great focus to the vocals. So, I messed around with the speaker positioning - toe in, out from the wall, closer together, further apart - nice but imaging not up to scratch which is not what I expected from the Harbeths.

Then I thought - hang on a minute, don't tell me I've made the most fundamental of mistakes - you know where I'm going here.... so I reached around the back of the amp and swopped the right speaker terminals around - BINGO - great imaging and tighter, deeper bass - yes your foolish scribe had been listening to his new system OUT OF PHASE for the first few tracks :NADowner:

The consolation is that it actually sounded pretty good out of phase but then really came into its own, of course, when wired up properly.

Anyway, I'm chuffed to bits with the sound - the only slight annoyance is the pop/thump that happens when the eVo2 is powered up - I guess I can just leave it on all the time but I'm suprised an amp of this price/quality should do this.

Matt.

 

Might be wrong but I think that "pop/thump" happens on most amps when you turn em on. Isn't it the protection circuit kicking in? Its a mechanical one on my ye olde Marantz 66 KI amp, but on the arcam a85 and cyrus that I've demmed at home they've both done the same thing as well.

 

Nice setup you've ended up with there. Should sound fab.

-- Ian

 

I must confess I listened to my 22Ls (biwired) with the bass cones out of phase for the first fifteen minutes I had them. A rather curious effect, and not a terribly pleasant one - I spent quite a while wondering how they could possibly sound so completely different to the 21Ls I'd just unplugged, and then suddenly twigged when I shoved on Subterranean Homesick Alien from OK Computer and there was no bass pedal note at all. :shame:

 

I have a lovely little nait 3 that I am really enjoying the sound of, and that pops.
Its actually d.c. when you switch on, and then the amp settles down, most japanese amps have a relay to switch out the circuit until things have settled down, together with a delay which then operates the relay, so all you get is a click.
Some british amps do seem to give this a miss, not all, still like I said, jap stuff is very good indeed for lots of reasons.
I did find in my room the bass of the harbeths was a tad wet lettuce, a bit limp low down, it was there and all, but it was in its own good way coloured.Nice spx tho

 

The click/pop is particularly inherent to class D amplifiers because when you have 0 signal on the input, the output is still switching at a 50/50 cycle between the rails. If you have a btl output, both outputs will sit halfway between rails (which are likely to be 0 and 50V or so). Afaik the belcanto is a single ended output (hence you can bridge them, which is not possible with a btl as it is essentially already bridged).

 

Ah - so the pop is just one of those things I'll have to learn to live with - presumably there's no problem with leaving the eVo2 on constantly?

I should also have mentioned that I ended up going for a Chord Chorus interconnect in the end - picked up a used one for £100 which I felt was pretty good value for a rated cable. Also bought one of those 6 gangs off that bloke on ebay - quality seems really good - can't knock it for £40 really. Haven't bought any power leads but might get a couple of Eupens when I get around to it.

Matt.

 

Matt,

Leave it on, there is no problem with that.
AS for the pop, don't suffer from that all, not heard another do it either, THOUGH some amp on/off switches are prone to sticking a bit, whip the top off (after disconnecting the mains), remove the circuit board behind the front panel and a quick dose of switch cleaner, then sillicone lube. Sorted.

 

Mine doesn't "pop" either,when I have had to turn it on or off,but I do as Tony,and leave it powerd up,the only pop I ever get is through the Rega P25so I turn the pre off first,then no POP.

 

No thumps or clicks heard through my speakers either when cycling the power on my Evo2i. All the Evo amps I've had experience with usually have a solenoid muting relay which kicks in the mute the speaker outputs when the power is switched on/off.

The nice thing about PWM amps I find as an added bonus is the idle current is next to nothing, in the case of the Evo2i for example the user manual states it's a mere 15W. So makes for cheap electric bills if you like to leave your kit powered up 24/7.

 

My DIY PWM amp (based on LC Audio ZAP Pulse modules) sometimes makes a little "click" sound on the speakers when you turn it on, other times it doesn't. It's odd that it occurs the instant you flick the power switch on which is before the modules have received any power as the soft-start relay on the PSU hasn't kicked in yet.

Much more strange is the sound that happens when I switch it off: after a few seconds I get a high pitched whistle which then drops gradually in pitch for a couple of seconds (rather like the sound of tuning a SW radio) and then with a couple of small "thuds" (one in each speaker), ends. It's all very quiet and I'm not worried about it. Would be interesting to know what causes it though.

Mike.

 

instability??
capacitors discharging?

Isaac?