Your thoughts on the following amps...

After saving my speaker from melting a second time I've decided to give up on the DPA pre/power and buy a used integrated amp for around £300 - £500. Would appreciate any views on the following:

Primare A20 Mk II
Sugden A21a
Roksan Caspian
Exposure

A good match for the AVIs and reliability are important.
Varied music, not much classical.
Other suggestions welcome and I may even buy your old amp if it fits the bill!

Thanks for any help,
Steve

 

What's the problem with the pre / power? I've had a lot of dpa kit and quite liked the 200S I had- if I recall it was a similar circuit to the 50S but with the balanced connections and speaker feedback stuff removed? If you like the clean dpa sound then the primare or sugden would be OK - the sugden may be a little tame. You'd probably like the Caspian but it's not as "dynamic" as the dpa. Can't comment on the exposure.

 

i recently owned the Primare A20 Mk I - which was great, but I sold it in the hope of getting a mk11 - thats supposed to be better...
on fleabay - an exposure 3010 went for 370 quid -
http://cgi.ebay.co.uk/ws/eBayISAPI....m=170167614609&ssPageName=STRK:MEWA:IT&ih=007 so that's also in your range in case you thought that you could only afford the 2010s...it's supposed to be a stonking amp too

 

Neil - Here's the problem with the power amp as Felix (Martin) discovered a few months ago. He fixed it for me (top man) but when switched on the second time heard a loud buzz, as before, and one speaker (bass driver) felt warm so I switched everything off. Anyway, here's what Martin said -

Well it is a bias problem, but it's a very subtle, thermal one... that took a while to spot!

The driver stage uses several MJE340/MJE350 transistor pairs. These are not fitted with any form of heatsinking, and on both channels this is asking one pair in particular to put up with 2.3W of dissipation in a package that can deal with about 0.6w in free air. IOW, part of the driver stage is running way over 100degrees C. When you do this to transistors, their current-gain drops, as does the turn-on voltage. This means the input stage has to work harder, but turns them on further...leading to eventual loss of offset- and bias control. Clearly the amp has put up with this for years, but one day cried enough and the failing driver transistor led to a loss of DC balance - which pushed several volts of DC into your speaker.

It's a problem that only appears once the amp is good and hot. Run up from cool, as I did when it arrived, and it behaves as nice as you like - clean scope traces, DC conditions stable, no sign of VHF instability anywhere. As it warms the DC offset drifts a little, as does the bias. Things only start to go awry when the amp is driven into a load - the issue *doesn't* show-up just sat on a bench hot but idling. And let it cool down and all is well again...

The fix is to provide heatsinking to the affected driver pair each side. Because overheating these parts has degraded their properties I will replace all 14 (7 in each channel - 55p each at Farnell) of these transistors, and fit clip-on heatsinks where required. In fact one of a pair has actually failed, but because this is inside the inner feedback loop the amp has 'worked around' it. Guess which channel!

I replaced the driver with the last one AVI had so don't want a repeat performance! That's the reason for the change.

Mr Cat - I bid on the Exposure to about £350 but was out at a gig so missed it.

May have a punt on the Primare, I've liked what I've read about it. Thanks.

 

I really like Exposure equipment, esp the older models.

I find really involving and toe tapping, get up and booggie !

If you find any 14's 9's 16's let me know !

 

Get a Sugden and sell the speakers for something good...

 

I agree with Alex about the speakers and while I love Sugden you won't believe what this thing can do. Bloody cheap too - http://cgi.ebay.de/Lavardin-IS-Refe...ryZ23325QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

Why would you get rid of the speakers? For the money (£250) I think they're pretty good. What amp and speaker combo would you buy for around £800?

 

I use a Sugden A21ai, and the better the quality of the stuff I hook up to , into/out of it, the beetter it sounds, I use it with fabers, and the SDT 1 CDP, sounded okay, borrowed Isolda and a Basis mains cable (a grands worth) and my jaw nearly hit the deck it was that good. It will outlast other upgrades for years. My fabers are only 86db sensitivity and sound great with it.