SDA-1B's and Adcom GFA 585

wingzam

You guys warned me but I just could'nt keep my foot out of it.Pushed the Soundcraftsmen RA7501 too hard and am now getting a low sizzling,clicking type sound at zero volume.Figure this is coming from the amp unless advised otherwise.Am now looking at an Adcom GFA 585 with 450watts@4ohms which is about all the budget can bare.This time i'm doing what I should have done the first time I went shopping:ASK the Polk crew if the amp is a good choice!!

george daniel

Is the 585 a common ground? IIRC, it's not,,,fire off a pm to H9,, he should know for sure,but I don't believe it is. So,,you may want to squeeze that trigger slowly.Have you tried the speakers with another amp,to make sure they are functioning properly? Good luck.

wingzam

The common ground issue has been tackled here in my previous posts.I can reconnect my integrated amp to see if that makes a difference,but bottom line is this amp I have just does'nt have enough juice to suit me and can't push these speakers into the sweet zone that I can hear they're capable of.Adcom was recommended by the crew albeit the 555.Did'nt even know the 585 existed until my visit to ebay.They were a limited run..like 2000 or 3000 units sold and going for affordable prices now.I fear my problem is that i'm a sound pressure Junkie..give me more power and i'll just want more and more!This may have it's insidious roots in my former path as a jet engine mechanic,hot rodder and dirt biker..there is nothing more beautiful then the sounds of a jet engine wound up to full throttle in afterburn,uncorked headers on a high horsepower engine,and a screaming 2 stroke engine..it..it..brings tears to the eyes just thinking about it...excuse me i'm getting all teared up...

george daniel

Not to derail,, but,,I used to be the same way,, as far as SPL is concerned,so with that in mind,, my question is,, regardless of the amp size/power,,, are the current SDA's gonna be loud enough for you?It I wanted "sweet loudness",,I'd probabally pick up some vintage Klipsch with some tubed mono's. Good luck with your amp search,,I've owned alot of the 500 series adcoms,,currently have a pair of modded 565's,,,the 585 is a monster,,for sure. :)

ben62670

Make sure you tie the grounds together on the 585. You most likely know that. It is like 2 565's in one chassis. It has two completely separate input boards, and you will blow the input resistors. The 585 is a monster like George said, and you are not going top get hardly any more with something else. You need to check for DC offset on the amp. Also the 585 requires 2+ full clean volts for max output. This is not very common with Pre's. Also inquire about the caps in the amp. Has it been serviced yet?

wingzam

Ben what is DC offset?I'll test for the 2 volts after I post this.That this is not common with Pre's shows me where this leads...better pre-amp.But let me check this one and see what I get.To George i'd have to say i'll know how loud is good enough when I get there!...Of course there has to be a cut off point....this is not a situation I anticipated when I simply wanted to upgrade my little stereo.The SDA's have become a tar baby that I need to keep from turning into a tar pit!

wingzam

Well I don't know what i'm doing.Took a voltage measurement at the Pre outs and got nothing.How do I check this?

ben62670

You really need special equipment to test for the clean signal out. The best thing to do is find the specs for the Pre's outs. Like amps some Pre's get a little happy with their ratings. DC offset is measured with nothing connected to the amp. Power it on, and set your meter to 2vdc to start. You measure across the pos and neg terminals on each channel. If the voltage is real low set it for mv. You should have less than 24mvdc in the Adcom's.

wingzam

Made contact with the seller who says there's no leakage at the caps and was serviced a few years ago.Will see if he'll check the DC offset.When measuring DC offset what level should the volume knobs be set for?

ben62670

There is no volume knob. You don't want anything hooked up for this yest. Well It has to be plugged in and turned on;)

Ben

wingzam

Oh,I was looking at my amp which does have knobs and see that the Adcom does'nt...

gdb

wingzam wrote: »

The common ground issue has been tackled here in my previous posts.I can reconnect my integrated amp to see if that makes a difference,but bottom line is this amp I have just does'nt have enough juice to suit me and can't push these speakers into the sweet zone that I can hear they're capable of.Adcom was recommended by the crew albeit the 555.Did'nt even know the 585 existed until my visit to ebay.They were a limited run..like 2000 or 3000 units sold and going for affordable prices now.I fear my problem is that i'm a sound pressure Junkie..give me more power and i'll just want more and more!This may have it's insidious roots in my former path as a jet engine mechanic,hot rodder and dirt biker..there is nothing more beautiful then the sounds of a jet engine wound up to full throttle in afterburn,uncorked headers on a high horsepower engine,and a screaming 2 stroke engine..it..it..brings tears to the eyes just thinking about it...excuse me i'm getting all teared up...

Dear wingzam, I don't mean to tell you your business or preach but.... I also have subjected my ears to very loud noises in my lifetime, like fireams,shop tools,open exhausts etc. I regret not wearing hearing protectors now every day because I've got serious hearing loss and tinnitus (constant ringing),all that makes me "miss" a lot of the music that I listen to and it just plain sucks! Please consider protecting your ears from any loud sounds that aren't musical ! Sermon Over;) Geoff

danger boy

gdb wrote: »

Dear wingzam, I don't mean to tell you your business or preach but.... I also have subjected my ears to very loud noises in my lifetime, like fireams,shop tools,open exhausts etc. I regret not wearing hearing protectors now every day because I've got serious hearing loss and tinnitus (constant ringing),all that makes me "miss" a lot of the music that I listen to and it just plain sucks! Please consider protecting your ears from any loud sounds that aren't musical ! Sermon Over;) Geoff

Geoff, good point.. once you damage your hearing, it's damaged for good.. no turning back the clock.

I attended a pop concert last Friday, then a hockey game with 10,000 fans the next night.. my ears were hurting by Sunday. Time to lay low for a week or so.