To biamp or not to biamp; that is the question~

I'm starting this thread for erniejade1 to get it out of another thread where it was started: http://www.carveraudio.com/phpBB3/viewtopic.php?f=15&t=11746&p=113730&sid=6cd2ed9af0f6fbc5ae15bcf8fae334bf#p113730

I am sorry to ask this on this tread but... On my ALS originals,, I find myself turning up the treble or on the bass unit ( the one for the ALS I cant recall the model number) I turn up the highs and keep the bass actually at -2... I do find the on flat a bit on the dark side. My question is if I do the bi amp trick, will that help brighten them up? Do I have to have 2 amps or with my Sig II 625X2, can I just run the voltage out and current out to the tops and bottom? Or will I not get the full benefit of doing a true bi amp?

I do have a Rance AC22b ( XLR only though so I would have to get a rca - xlr adapter) so a electronic crossover would be no problem.

Thanks and sorry to ask on this thread but, it is on the same subject...

Equipment,

Sunfire sig II 625 x 2 carver c19 pre Jolida cd100 cd. Technics 1200 with a Denon DL160 cart, From the Polk board ben's cables for IC's On the Sunfire I have it on the voltage out.. The current is just too much bass on the out.


Speakers are 3 feet from the corner, about 1 foot away from the wall. Cement basement! 26 X 24. The speakers are on the 24' side. I do have the amazings on carpet squares.



Next to them I do have a set of polk sda 1.2 running on the same as above except the amp is a McIntosh mc2105. ( I love that the c-19 has 2 sets of pre outs.

and here's Steve's reply:

I am sure Gary will chim in here..I also have the originals , I put a BBE sonic maximizer ( 422A ) Its a 2 channel...I have found my ALS,s to be on the flat side with out the 422a...I do not have a problem adjusting the treble ( +6 )OR bass ( +2 to 5 any less and they sound REAL flat ))to open up the ALS,s....I do not have the treble or bass flat on TGP////..I have found that my ASLS,s need to be pushed aggressively , if that makes sense...I like my stuff bright and boomy , with the mids in your face , so I will not have the treble and bass straight up and down..Like Bob always says " I dont know , lets try it...!! " oh , I have them connected to the voltage side of the amp...Current side made the ribbons sound real flat and skinney...When I Paradigm speakers , tone controls where straight up...Adjust tone controls to the + side , and take a listen...

So now we can start fresh & not pollute the other thread~

Personally, if that setup sounds "dark" to you, you either have some equipment issue or your ears have a problem. And aren't Ben's cables made from silver? I can't imagine a C-19, silver ICs, Sunfire Sig amp, and Plats sounding dark in a concrete-floor basement.

That said, while you CAN actively biamp & raise the power level to the ribbon side, I'd believe you'd cause other issues that would need to be addressed that way. First, we need to figure out why you feel you need to brighten the ribbons. What speaker wire are you using?

I found the BBE unit to sound WONDERFUL with my AL-IIIs...does it not work magic for your Plats?

How far apart are the speakers? If you're 3 feet from the walls on a 24' wall, that means they would be @ 18' apart...DAMN! That would put your prime listening position about 22-24 feet back into the room! I'd pull them back together some, 10-12 feet apart MAXIMUM, and get them out from the back wall another couple of feet if you possibly can.

Active biamping will definitely do a minimum of two things for you:

1. Increased headroom from the amp
2. Clean up the upper range to a certain extent (not brighten necessarily, but probably make "clearer", if that makes any sense) by separating the bass frequencies from the amp driving the ribbons (cut inter-modulation distortion).

There may be other ramifications/enhancements, depending on a number of factors.

Thanks for the startup !!

Mine are the original not the plats. 2 X 30" .

Yep bens cables are silver. I was using AQ Columbia's but on my system, I found ben's cables just smoother all around.
I do love the BBE unit but, the carver unit has the sonic holography on it. I sometimes go between the 2 ( I love the C19 has 2 processor instead of 1 LOL) The BBE does a better job of bringing out the highs then the carver unit but the carver unit does a better job at the bass. Also with the carver unit, as crazy as it might sound, does a wonderful job with the POLKS!! You keep it all flat and hit the sub bass button WOW they explode!!!!!!!!! The bass just jumps back to life. ( i am also using ben;'s IC about 100 hours on it now. )

I can move the speakers that is not a problem. I have pulled them closer together before and all of the bass disappeared in the center but, let or right of the speakers was just the most bass I have ever heard out of them!! . ( I posted this one up here before and I believe F1 said it was because my room was too square ) BUT I have not moved them up! I will try that next!!! I listen o them about 10 feet back. I tried going back to around 15 feet but OMG the bass was way too much ( probably because of the square room again)

For speaker wire, I am using acoustic research 12 awg. For the $ not bad at all. It could be because also I have the Polk SDA 1.2 down there . I go between the 2 speakers depending on the type of music and the polks are bright.
.

For the polks the 2 things that helped me with them are 1 the C-19 ( night and day from the adcom 565 i was using ) and the McIntosh amp on the 4 ohm taps made another huge difference.

The amazings, I do love them but I just cant find the right position for them... Again.. it might just be my room. One day I should put up a wall and section it off like cut it in half.

Well, if it's possible to do, your optimum position for the Originals would be 10-12 feet apart (MAX), at least 2-3 feet from the back wall, & YOUR listening position should be slightly rearward from an equilateral triangle formed between you & the speakers. If you bring the Originals together more, you said your bass disappears, but when you move back it enhances. So if you bring them together & move your listening position back, that should put you in the proverbial sweet and juicy like these nutz. spot & smooth out the bass...right?

Close lol. when I brought them at 8-10 feet apart, 8" from the wall i could be 10 or 18 feet out and the bass would just disappear. BUT if I went to the extreme left or right of the speaker it would be thumping like mad. I originally thought them to be out of phase but, the + was to + and - to -. I have not tried moving them away from the wall though.... I will give that a shot next@@!

What you're describing is indeed an out-of-phase condition. If you swap the speaker leads, does it sound better, or worse?

I'm guessing the placement of the speakers might have something to do with it...
The ribbons are very directional. If you aren't in the "sweet and juicy like these nutz. spot" the ribbons can sound dull.
Make sure the speakers are toed-in enough, and each ribbons is almost pointing at each of your ears. 1-2 degrees can really throw the sound off ALOT with these ribbons.

The OTHER possible problem could be the ribbons themselves... 20-30 year old ribbons can, and do flatten out sonically over the years.
I just replaced my fathers ribbons last weekend, and man, what a difference. They are much brighter now, than they were with the 4-5 year old kapton that was in them.
I was surprised at how much brighter they were. I expect them to tone down, as the old manuals say 100 hours break in time for them anyway.
But before and after... BIG difference.

Hope something here helps.

James

This weekend I am going to try moving them again. If not, then i am going to think the ribbons as James said and look into different ribbons... Heck if I go that route, wouldn't I be better off going the 60" route then getting the 4 x 30" repaired? Probably cheaper... ?

I can see them dulling down though over time.


Thanks everyone for the help. After I move them around again I will let everyone know!!

ernie, you have to upgrade the crossover as well, unless you just go full active crossover.

That is what I was thinking. Just go with the Rane ac22 for the crossover. ... part of me is hopping it is just placement the other part is hopping for new ribbons. LOL.

OK here is what I have done so far, I moved the speakers 10' apart. the ribbon is 2 feet away from the wall and the woofer end of the speaker is 32" away from the wall. I do have room to play with moving them away from the wall since it is in my basement and basically my room with only audio stuff and a pinball machine in it. I was sitting 10 feet at the tip of the triangle. moved to 9 feet and it lost some of it's lusture. That did help, although I don't have as much of a slam in the low end as I did but, it did sound better, a bit more cleaner and a bit more authorative. I turned on the carver bass correction unit, hut the sub bass button, and BOOM it came to life. I then changed out the speaker cables. I was using AR 12 Gage wire and changed them to audio quest type 4, the highs were much clearer. ( i used the Beatles LOVE CD as a test)

I still need to tweak the position of the speakers more but, so far, this has made a huge difference. I will next try it at 9 feet and see how it sounds and play with the tilt more. so I think it is a combo of the position, and wrong cable for them. What is funny on the cable, on my Polk 1.2's the AQ was not so hot so i never tried them on the carvers... my mistake!!


I will update more as I tweak it more.


It is better but I still think they are a bit dark. ON the carver bass correction unit, I have the high up all the way. the bass knob only turned up 1/4 with the sub bass button on. Without the sub bass button on it go flat but with it on, it is too much and gets muddy.

Did you ever just try swapping ONE of the speakers leads to see if something is out of phase at some point in the chain? Hell, a mis-wired IC would cause the condition you posted about (bass off center, non in the middle)....

Hi yes i did reverse the + and - on the back of the speaker. Now I have never been inside the speaker on the left but the one on the right i was in when i replced the woofer 2 years ago. The left one though does have 2 different color ribbons, ( 1 gold 1 silver color ) while the right one has 2 gold ones so .. Maybe I should pull the cover off the left one and make sure nothing was wired out of phase inside it. Or to see if anything else was done when whoever replaced the ribbon.... Humm.. Might be a Sunday project to make sure the woofers are wired the same on both sides...

Now sonically the ribbons silver or gold sound the same but the color does throw the looks off LOL.

Forgot to mention when i reversed them, it got that caught in the middle efffect so the general part is not out of phase.

erniejade, did you ever get this fixed?