Arcam A19 + P38

[unsleepable]

So for a while I've been thinking that my next upgrade will be a preamp+DAC. I'm happy with the sound of my current setup, but the A19 has a bunch of analogue inputs of which I only use one, to my DAC. And I use three of the DAC inputs to different sources. Somehow, it'd make more sense to manage volume and input selection on the same device.

Preparing for this, the first I needed is a power amp as the A19 does not have a direct or AV power input. And I've been able to get a hold on a second-hand P38 at a decent price, so I've gone ahead and bought it. It will still be a few days until I get it, though.

I've been checking how to connect the A19 and the P38 and I have two options: either using only the P38 for power amplifying, or in a bi-amp setup. I think I will play with both as the A19 and P38 produce distinctly different sounds and I am curious as to how a preamp and a power amp sections affect the different qualities of the sound—such as maybe airness remains similar with both power amps, but tightness will differ, and stuff like that. This promises to be interesting and should keep me occupied for a while.

Now, I've never tried bi-amping before, so I don't have any experience with it. But checking the setup recommended by Arcam in the A19 user guide, a question has popped in my mind and I hoped someone with more experience could help me with it. The setup is the following:

And my question goes like this: if the preamp section of the A19 controls the volume of both its power amp section, and of the P38, and these are connected to the LF and HF posts of the speakers, respectively, shouldn't the volume of the LF be higher than that of the HF taking into account that the P38 has double the power than the power section of the A19? The obvious answer for this should be no… Otherwise, it wouldn't make sense that Arcam would recommend this setup. But then, I don't know why.

It could also be that the preamp output of the A19 is volume-matched to the P38. But then, does that mean that it wouldn't work well with another amplifier that has different power? And this would also imply that the A19 wouldn't be able to achieve the maximum output from the P38, as the upper limit would be set by its own internal power amp section.

I'm sure this is much easier than I see it at the moment. Hope that someone with more experience in bi-amping setups can shed some light over this. Thanks!

 

[unsleepable]

Bump?

 

[davedotco]

In any bi-amp setup you need the gain of the power amps (whether separate or part of an integrated) to be the same. Ie the same input level applied to each amplifier gives the same output. The power rating really does not matter.

Most manufacturers will match the gain on their various models so I am reasonably confident that the Arcam will be fine.

Personally I find bi-amping in this way to be of little benefit, the bass amplifier, presumeably the A38, will be providing 90+% of the power in any case, no great advantage to be had there.

From this position i would be looking to sell on my A19 and Dac using the money to buy the best dac/pre-amp I could then afford.

 

[crusaderlord]

Try the combinations and see what you prefer. Personally i would probably just use the P38 as the power amp and the A19 as a pre amp and the irdac as the dac. Selling the A19 and irdac is an option but the irdac is so good it may be pretty hard to get that much of improvement without spending far more money. Also the A19 is probably well balanced for the 38 given the same manufacturer. The older Arcam c31 pre amplifier may be worth a look to replace the A19 as prices are often quite low. Initially i would try and A19 with the P38 and see how happy you are. I love my A38 integrated and it has more power than i will ever need to drive my speakers.

 

[unsleepable]

Thanks for the responses. My plan is not really keeping a bi-amp setup, but eventually doing as suggested and replacing the A19 and the irDac by a preamp+DAC.

I may even try, just for the fun of it, the irDac directly into the P38 and doing the volume digitally as discussed in another thread. Although I seriously don't think that would stick either.

But first of all, I need to see if the P38 sounds better, or at least equally as good as the power amp in the A19, and the change is worth it.

 

[Stenninski]

I no this is old now but what we're the results. I have the a19 which I am happy with but just feel there's something missing, I love the sound of my dad's a38 and have been looking into using the p38 and the a19 as pre.

 

[hybridauth_Google_107074969209142745862]

I would like to get some feedback on this setup as I have an Arcam fmj a19 and IRdac paired with B&W 685's. I am also thinking of getting a second hand Arcam P38 to be used in a bi-amped setup.

 

[nopiano]

Unfortunately most of the contributors appear not to have logged in for over a year, so don't expect to hear from them. Perhaps they are blissfully enjoying their uprated system, or maybe they never bothered!

What Davedotco stated is worth re-reading.

 

[davedotco]

Worth adding that in a passive bi-amp setup, the power of the system is the power of the least powerful amplifier. Both are being driven full range so will clip as normal when overdriven, sure you get a little more headroom with the bigger amp but audible differences will be marginal at best.

More upheavel I guess, but the best solution is to buy a better amplifier. Maybe get something with a built in dac, a used Hegel maybe and simplyfy and improve, H80s can be had for around £1k.