Cambridge Set-Up On Its Way!

[zenith2134]

Hey all, how've you been?

I haven't been around here much since joining but its time to change that.

Last night I bought a Cambridge Audio 640A version 2 and 540P RIAA stage from AudioAdvisor's online store. With shipping, total was $526 USD and change. Not too bad considering the good reviews I've been reading.

These will be my first C.A. products and I cannot wait to hear them. I plan on running these with my Pro-Ject Debut III and Macbook Pro as sources, with A/D/S L-780s as the speakers. I like these speakers since they have a very flat response and are never harsh even with rough programme material. I rewired them internally with 14 gauge copper wire (original was 22gauge) and reworked the crossovers to bring them up to date. Previously, I was using a vintage Kenwood KA-8100 with these.

Anyone on the Art of Sound using the same or similar C.A. system? What tonal qualities should I be expecting?

[John]

Hope the system works out well.
You should be Ok with the Cambridge gear; but in future try and hear stuff at home with music you know well

[bong]

CA gear is fairly common when I'm from, and well regarded as reliable entry level audio gear. it does its job well for the price, and most change only when upgrading to something costing quite a bit more, rather than because of dissatisfaction from its performance.

[John]

Agree Cambridge Audio is good value and should sound good; just saying best to always hear gear at home if you can, it helps to avoid mistakes!

[zenith2134]

Thanks for the tips! I certainly agree that its very wise to audition gear as it will be used (and with familiar music) but I have taken a chance before and expect at least half-decent results. I mean, I was using a 30+ year old SS amp that needs new capacitors and probably could use faster silicon components to even come close to this Cambridge.


Naturally, Specs don't tell the whole story, but here's some food for thought:

Previous amp: Slew Rate was 7v/uS; Damping was 50; power output was 75wpc@8 ohm and 90wpc at 4

Cambridge 640Av2: Slew rate of better than 30v/uS; Damping of >110; and power output of 75wpc at 8 and 120 at 4

Not to mention the shorter signal paths incorporated into newer gear. The old stuff has dual filter switches for both high and low frequencies, a 3 way Loudness switch, stereo reverse button, and some pretty awful speaker connectors.

I think this will be quite the upgrade for me.

[zenith2134]

Enjoying it as we speak!

Must not be too junky.

The amp has a full sound......sorta like it's very transparent yet places emphasis on the bass at times.

[bong]

great to know that it's working well in your setup, and welcome to the slippery slope of hifi upgrades ... ;)

[Beechwoods]

Hi there, glad you like your new English hi-fi kit! I've not personally heard the 640A but I have read that the initial bass emphasis becomes less evident as the amp burns in. Let us know how it develops!

[Filterlab]

Yes, definitely give your new equipment about 100 hours running in until you make a firm judgement. Most importantly, enjoy!

[zenith2134]

Thanks! I kind of like the exaggerated bass since my woofers are only 8.25" each.

So dar, its got less than 4 hours on it :) I experienced headphone break in with my Grado sr325i's and boy did they improve.

The manual for the 640a says it takes several hours a day, for one week before full sonics are realized.

How long are we really talking here? Standby mode doesn't count, correct?

Should I play Pink Noise from my soundcard at very low volumes?

[Filterlab]

There's a few things you can do, hi-fi components run in at even low volumes. You could play pink noise but you'd be better off putting a CD on repeat. As for burn in times, it varies from a few hours to hundreds of hours, but I'd say 50-100 hours would be fine for most components. Standby doesn't count unfortunately, although it does keep things nice and warm and ensures (in a lot of cases) a quick warm-up.

[bong]

to add to the running in advice, i normally use an old fm tuner that I keep aside as a source to run in any gear further along the chain ie pre, power, speakers, cables etc. i find it the most power/cost effective source to use cos of the low power consumption, no mechanical parts/laser to damage or wear out. but since you've listed your computer/laptop? as a source, you can also hook that on and just repeat your entire collection of digital music a couple of times.

out of curiosity, what made you decide on the 540p stage as opposed to the 640p? if i recall, the price difference between the two is minimal (relatively) and the 640p gives the option of MC and is generally well regarded.

[zenith2134]

I chose the 540P mainly because I don't need an MC input, nor do I need a subsonic filter in my system. Just didn't see the reasoning in spending the extra 80 or so bucks.

So let me get this straight: If I leave the unit(s) on 24/7 for say, a week let them see signal only whilst listening, is burn-in taking place?

[bong]

i see. you have great discipline ... the upgraditis bug bits me on a regular basis. :D

as for running in, i think as long as there's a full signal from source to speakers/headphones, running in should take place. not sure if it's true, but i read somewhere that if you're running in a pre or power amp, if there's no load at the end, ie it's on mute or the volume is zero, there's no burn in or not as effective.

[zenith2134]

I think I agree. Whenever I burn-in interconnects and wire they need a load.

I'm loving this kit already....and man it's definitely improving by the day.

Interesting thing about burning-in with headphones: I read that this amplifier incorporates a small, seperate class-a headphone output circuit. When a headset is inserted, a relay clicks the speakers off, and leaves only headset output.

So, isn't that technically an additional amp stage needing burn-in?

[bong]

true true .. i forgot that most amps with headphone outs would have a separate circuit for it .. and i don't think you can burn in speakers and headphones at the same time ...

[tfarney]

I've read nothing but good things about that amp, and particularly high praise for that little class A headphone circuit. Yes, the speaker amp and headamp will need to be burned in separately. And when you're done and it's time for a full report, this headphone geek would like to hear as much about that section as the speaker amp. :)

Tim

[zenith2134]

Well, run-in is just about complete. I have roughly 75 hours on the speaker outputs (pink noise 24/7) and the same or even more on the dedicated headphone amplifier output stage.

This amp improves A LOT during the first week of ownership;the memo in the manual was NOT lying.

I reckon that the phono stage is the only part which needs some more burn-in time, although it is very enjoyable at this point.

TFarney, I'm a headphone addict too. I use Grado SR325I and AKG K240's. Sold my Sennheisers (HD555) to fund the Little Dot MKII tube amp but honestly I may sell it.

The Cambridge has an astonishingly good headphone sound. with 32ohm nominal cans like my Grados, the 640A V2 kills the Little Dot in terms of power output and soundstage.

My theory is that since its solid state, it has the necessary current to drive 32 ohm cans whereas the Little Dot is better at high impedance loads.

The fact that it runs in class-a makes for some awesome listening.

Overall, highly recommended.

I'm listening to an original LP of Bauhaus' 'In the Flat Field' and its never sounded better. :):)

[tfarney]

TFarney, I'm a headphone addict too. I use Grado SR325I and AKG K240's. Sold my Sennheisers (HD555) to fund the Little Dot MKII tube amp but honestly I may sell it.

The Cambridge has an astonishingly good headphone sound. with 32ohm nominal cans like my Grados, the 640A V2 kills the Little Dot in terms of power output and soundstage.

I've had a handful of dedicated headphone amps in the house, tube and otherwise, and remain unconvinced that most of them out-perform the headphone stages of quality integrated amplifiers. If you get into the very high-end, I'm sure there's an edge, and if you're using very low impedance phones with an amp that powers the headphone jack by stepping the mains down through resistors (the most common approach) some say that audibly affects the FR. Doesn't seem to phase hi-impedance cans, though. And for my Senns, the differences between dedicated hp amps and good integrateds or receivers have been very small and very much a matter of taste.

With the Cambridge in the house, I would think the Little Dot is redundant at best. Even if you someday go for a very difficult load like the HD600s or 650s. YMMV and all that...

Tim

[Filterlab]

Glad you're enjoying it Zenny, definitely give it more time to run in completely, it'll improve gradually over the months. The phono stage will take a little longer as the input voltages are lower, but it'll catch up.

Lovely to hear someone enjoying their hi-fi.

Nice one. :)

[zenith2134]

The Little Dot is on Craigs'list and I already have a buyer. :cool:

Here's the system as it stands now: ProJect Debut III w/Ortofon OM5E into Cambridge 540P, Sony SCD-CE595 SACD changer, Proton 420 analogue tuner, and MacBook Pro via USB DAC into the Cambridge 640A with ADS L-780s and Grado SR325i's hanging off.

Called a local gent and may be getting L-880s or L-1290s to replace the smaller 780s!!!