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Help Needed Power Amp lacks punch

I just got a used supposedly high power Adcom GFA-5500. Had it run in for a few days and found that this amp has got very weak bass punch. No unusual noise or hum. Got everything but bass punch. Asked the dealer he said it's because the amp is not powered for a few months and it needs time to charge up those hugh capacitors. Asked a technician and he told me it could be a faulty capacitor or maybe also a transitor fault.
I don't know who is right and I hope that someone can give me some advise here.

I would like to know
1. how does faulty cap sounds like?
2. how does faulty transitor sounds like?
3. how long must it takes for a cap to charge up? and can that result in weak bass like lack og power?

Please help. Thanks.
rainchild
rainchild OP
31 posts
 
Thanks Sean,

I think this is too profound for me to understand. Should we go for tubes? I used a Electrocompanient ECi3 rated 70 watts class "A" before but I found that the ECi3 sounds more like a 40 watter to me. I also heard the YBA Integre DT and it sounds like a 150 watter driving a pair of Spendors. Matching equipments is a deep thing really. Can someone tell me what to use to drive a pair of Hales R2?
fetguy
90 posts
 
One thing to check is the receptacle in the wall; most all home wiring is done with "push pins" meaning that the house wiring is pushed into the receptacle where it is held in my tiny little contact points. By far the greatest loss is occuring here. I have seen cases where a drill-motor would hardly run!

Get an electrician to put in some hospital or industrial grade receptacles and make sure he wires then via the nice tight screw!

That being said I do remember that particular Adcom as being a bit laid back in bass transients. Get a Bryston (for instance). That is among a class of amps that are only beaten by Krell in the bass (and the Krell is not quite...well...right...). Plinius is another good choice, though I think that you get more bang for the buck with Bryston (dollar value and amazing warranty). Just my bias of course....
kgveteran
193 posts
 
I had no idea about my Adcoms and bipolar outputs.I guess that makes sense.Thanx for the info.
clbeanz
192 posts
 
Don't give up that 5500!Ihave one I felt exactly the same about,warm bottom.What it did have after break in of about hundred hours was very musical top end up to point where it shifts from A to AB(To my understanding 5500 is biased class A to 25wpc).
This second sytem with a 5500 doing mids and highs and a 555II on bottom fed via 565 pre-amp.The 555II had very good low end but grainy mids and highs,the 5500 has really good top end.My one worry about how the 2 truly different designs would playback through a single set of speakers was set at ease as coherence was fine.The 5500 sounds much better in this vertical bi-amp setup My guess is it can now remain in its class A zone for most listening levels having only to power the top.Also I placed the 5500 below the 555II to act as a preheater for the cold blooded 555II.
A step up would be a better pre-amp.But most this stuff can be had for cheap saw a 565 and 555 here on agon'.
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