What does 375 watts do to SDA-1B's

wingzam

The replies are great!The output is 375 watts@4ohms.Luckily have'nt smoked anything and now understand what the limits are.I just upgraded from 80watts with 40 year old 60watt speakers so it sounds pretty darn good to me-Neandertal that I am.Now can I get a unanimous yes or no that ohms reading at the negative terminals of less then 1ohm(how much less?) means that I can tie the terminals together?As far as the meter being off,its a digital and I don't think it can be zeroed(if it can I have no idea how).I'll check the battery right now and see what I find.

wingzam

Alright I changed the batt and now,with speaker wires disconnected,I get a reading that varies between 0.4 to 0.8 ohms...does this variation mean the multimeter is screwed?What the hell!Anyway do I tie them or not?

F1nut

What scale are you using? There should be a calibration point somewhere, usually on the back.

wingzam

Let me see.This automatically chooses the proper range,but now the variation is from 0.8ohms to 1.2ohms.This is a newer Craftsman multimeter and is apparently a piece of junk.Can't find a clibration setting and don't have the manual...see if I can find some info at Craftsman..

Dennis Gardner

My guess is that your amp isn't common ground. I have an new amp that is rated for 450wpc @ 4ohms that cuts out at anything above 90dB hooked to my SDA-CRS.

My common ground amps will drive them over 105dB at around 100 wpc.

wingzam

Ah,nothing like a little fitful sleep.After reviewing the posts to this thread i'm amazed at how many of you DON'T crank your stereos!Whats up with that!?OK i'll give you a break,I live just far enough away from neighbors that I can crank it and not unnerve people.Also I only crank in the later afternoon and I don't listen at those levels very long.Really,we who HAVE THE POWER must be responsible stewards of the audio spectrum.Gone are the days of extorting money from the community with the threat of "I'll turn it up louder".A new day is dawning when people everywhere can walk the streets secure of any decibel terrorist attacks.Bleeding ears will be a thing of the past and virginity will be guaranteed to all women well into their early teens!Good morning Forum and have a fun day!

george daniel

Well I for one "crank" it, but probabally not like you and others. I like to be able to "hear" the music,details etc, at a listening level that does not require you to have to max it out to be able to hear what I'm hearing, at a lower level,if that makes sense. It's been my experience that a high current(not necessarily watts) but both never hurt,amplifiers will get you there.One thing that I have learned though,, is Source,without a quality source,you ain't gonna' get what you're looking for at any volume level.You have good speaks,so you're halfway there. please don't misunderstand,,as you tweak/upgrade your system,those Polks are just going to sound better each step of the way.Just my .02 worth. Have fun with your rig,you're off to a great start.

tugboat

wingzam wrote: »

Let me see.This automatically chooses the proper range,but now the variation is from 0.8ohms to 1.2ohms.This is a newer Craftsman multimeter and is apparently a piece of junk.Can't find a clibration setting and don't have the manual...see if I can find some info at Craftsman..

Have you set the meter to its lowest ohm setting and shorted the leads together to get the resistance of the leads? If not, do so and note the value. You would then need to subtract that number from the number you get whenever you measure for resistance. My Craftsman DMM leads are .8ohm. If yours are the same value (or around that range), then what you're reading when measuring the grounds is just the resistance of the leads.

ben62670

tugboat wrote: »

Have you set the meter to its lowest ohm setting and shorted the leads together to get the resistance of the leads? If not, do so and note the value. You would then need to subtract that number from the number you get whenever you measure for resistance. My Craftsman DMM leads are .8ohm. If yours are the same value (or around that range), then what you're reading when measuring the grounds is just the resistance of the leads.

Excellent suggestion.
Thanks
Ben

tugboat

ben62670 wrote: »

Excellent suggestion.
Thanks
Ben

Found this out the hard way. Measuring some 5% resistors and they all were out of range by up to 10%. I called and complained and was told about the resistance of the meter's leads. Once I was in the know, I subtracted the resistance of the leads and all the values were under their stated 5% variance.

Live and learn.

wingzam

OK I got a 0.5ohm reading across the test leads.I was'nt getting exactly repeatable results with this multimeter.Was getting between 0.4ohms and up to 1.2ohms.So we're looking at a resistance value of 0 to 0.7ohms.With this high number in mind is it safe to tie the negative terminals together?

wingzam

As an aside,this amp came to me from ebay and was not in as cosmetically described condition so I contacted the seller who offered to refund my money with a return or give me a 50% rebate.I took the rebate,giving me a total cost of $117 which included a 10% discount from paypal.As I said I upgraded from an 80watt receiver (Pioneer SA-9500II) and 40 year old 60watt speakers.So concerning SOURCE,well,it sounds alot better..heck it sounds great to me.Now that I know that half volume is generally the point of clipping with this type of set-up i'm satified with what ive got.The few additional tweaks will be running a clean 3 wire power source to the system (instead of the two wire hooked to a three prong outlet) and seeing what happens if I can ground the Neg terminals together.I've never had a set of speakers that could handle this much power and did'nt know what to expect from them...you guys have been a huge help!

ben62670

I am pretty sure you can tie the grounds together. I just don't want to say yes, and you have a problem. If you go to DIYaudio.com and ask them there they will know for sure.
Ben

wingzam

All right i'll go ask them.Thanks..John

tugboat

wingzam wrote: »

OK I got a 0.5ohm reading across the test leads.I was'nt getting exactly repeatable results with this multimeter.Was getting between 0.4ohms and up to 1.2ohms.So we're looking at a resistance value of 0 to 0.7ohms.With this high number in mind is it safe to tie the negative terminals together?

Did you give the reading time to settle? I know that my DMM starts on the high side and then settles after about 5 seconds when measuring resistance. On my Denon I get .8ohm (test lead resistance) and on my Pioneer I get between .8 and 1.0 and it's a common ground amp. That would make it between 0 and .2 after subtracting the test lead resistance.

As stated here in previous posts, your amp should be common ground or you would have damaged it already driving it to such high levels with the IC connected. Strapping the grounds together won't do anything the internal connections aren't already doing. It's most likely a lack of current causing it to run out of steam.

That being said, you need to find someone that knows for sure about the grounding of the amp you're using. Post over in the site Ben noted.

wingzam

Yes I let the readings settle.When you say "lack of current" are you referring to the supply power at the wall outlet?And the conditon of the house wiring is a contributing factor to running out of steam?

ben62670

The capacitors are rather small for an amp of that power. During heavy use, or during bass passages the amps power supply will drop in voltage. This can cause the amp to clip which kills tweeters. It doesn't have anything to do with the outlet.

wingzam

Yes this is what Ken at Customer Service said.I guess for the question of upgrading the capacitors I would have to go to someone experienced with soundcraftsmen gear.One of the beautifull things about this amp that I noticed is the layout and ease of access to components.For instance the caps have screw on connections rather then soldered,so with a set of schematics it would be a cinch to upgrade....the question then is:Do I want to put that into this amp?Not right now..I think i'm happy enough with what i've got for the time being.For $117 i'll keep the amp around and look for something better when funds and opportunity permit.Aaahhhh,done with that problem!!NEXT??

F1nut

Again, you do NOT need to strap the grounds, so move on from that.

Upgrading the caps in your amp is NOT going to give you a beefier power supply. The best thing you can do is save up some money and buy an amp designed for home audio.

ben62670

I agree also you should get a better amp.
here is a link to mods done on that amp
http://www.diyaudio.com/forums/showthread/t-45988.html

well, I did swap out the big caps, and that is as far as I have gotten. I replaced the old 11,000uF caps with Aerovox M series 41,000uF caps, and the the 22,000uF caps were replaced with Aerovox M series 39,000uF caps. I also rewired the whole amp, rerouting wires to make runs shorter, neater, and increased the size of the wires between the AC input and the power supply transformer. The amp looks beautiful inside now, but more importantly, Just these mods alone made a huge difference in the performance. Like most people say, the bass was a lot more forceful, but it just all around sounds better. I do have a full set of transistors and the small bypass caps to go into the thing when I have time.

The PS caps are way to small for that amp. It has smaller caps than Adcom's smallest 100wpc amp

F1nut

Ah, upgrade as in replace them with bigger ones. Gotcha.

beardog03

buy a Parasound 3500 and be done !!!

ben62670

Nearly any Parasound, or Adcom will sound much better than that amp. Please don't take that as insulting, but some advice to get the most out of your SDA's;) Those two brands are great bang for the buck amps.
Ben

Edit: Here is a good deal from a Polkie
http://www.polkaudio.com/forums/showthread.php?t=73687

wingzam

I appreciate a good insult,especially when I don't know ****!! I'll check out the Parasound and Adcom.Being on the budget I am it may take awhile to save up for what i'm now looking for so figure i'll make do with what I have...in the meantime i'm putzing around with this NAD 2200.I resoldered some loose joints,but the thing is still popping fuses so will try one more thing and if that does'nt work I may just play around with it for the learning.I grew up in the TV/stereo sales and service business back in the tube days,which my dad owned,but rather then follow in his electronic footsteps I got into aircraft mechanics...not one of my smarter choices..do you see a pattern here?!

danger boy

i agree with some other posts... i like to crank it.. but my 40+ yr old ears can't take the volume anymore. Music to me just sounds better when it's at a slightly above listenable level.. and not hurting your ears.

wingzam

Admittedly I can only listen to about 3 or 4 songs loud and then only in certain parts do I really crank it.Then it becomes background music till i've had my fill.Thing is that when I do want to crank it I want to split atoms..it's a form of physical therapy!!

Saummisra

Does anyone know the difference between the Parasound HCA 2200 and 2200 mk2.
I have an option of buyng a 2200 and wanted to know if there is any diiference between this amp and the mk2
Thanks

Fatbrando

I hope this isn't considered hijacking, but has anyone ever run SDA's with a Yamaha M-2? Can't quite afford the parasound,etc....

FB

dracoskeeper

I'm just posting this so I can reach 25 so that I can post my Adcom 5800 and 5503 in for sale classified section!!!