DIY Biwire

Sthrndream

I have LSI 25s capable of being biwired. I have a Sunfire Cinema Grand 7 x 400 that has 4 terminals per channel for the left and right front mains. This allows for true biwiring and currently have 12 awg speaker wire (2 sets) going to each main.

With all the biwire speaker CABLES out there, am I to assume lets say Monster 2.4 will sound better than me taking four strands of 10 AWG wire and biwire both mains?????

Dennis Gardner

LSi25s can't be biwired in the conventional mid/tweet way. The bottom posts are inputs for speaker level for the subwoofer. The mids and highs are attached to the top posts.

Sthrndream

I dont think I understand what you're saying. My left amplifier terminal has 4 outputs for speaker wire 2 for current-2 for voltage. Ditto for the right. The current set is wired to the highs and voltage set to the lows. So in essence they are currently wired as you stated. highs and lows.

What my question is, there are cables out there that are 240 dollars. Wouldnt heavier guage speaker wire do the trick???? Its alot cheaper than purchasing a cable

ViperZ

Sthrndream, what are you talking about when you are saying "current" and "voltage"? These two terms are electronics terms and have no relationship to the naming of your terminals. What you terminals are: top is for mids and tweeters, bottom is for sub.

The signal that comes has amplitude and frequency. In this case, amplitude will be measure in volts. Current is the amount of "juice" your amp will be pumping to the speakers. But again, these two terms have absolutely nothing to do with how you wire your speakers.

Sthrndream

Im referring to page 14 on my Sunfire Cinema Grand 7 x 400 manual. It can be seen on the Sunfire website here: Linkhttp://www.sunfire.com/400SevenFrontPR.htm

Bottom line is : Im wondering if I would be better off going to Home Depot and buying some 10 AWG wire and making my own "cables" or buying the monster interconnects. I cant imagine the MOnster's would sound better.


tia

Chime in Please polkies

michael_w

Cables making a difference is really debatable. I personally have noticed a difference between cheapo cables and some higher end ones, but that's up for you to decide. If you can find a friend that can lend you some to see what you think.

If I were you I'd stick with a cheaper cable and then once you've had a chance to try out some better cables, then make a decision whether or not to go to a more expensive cable. FWIW monster cable makes some decent stuff but in general it's overpriced and a much better deal can be found elsewhere.

Dennis Gardner

The current and voltage posts on your Sunfire are there to provide you a choice of how to hook up your speakers to get different sounds from your amp. They aren't bi-amp posts to my knowledge.

The speaker posts on your LSi25 are different than most pasive speaker biwire posts since the bottom set go into the amplifier of the sub not to the speaker. The top post goes to the mid/tweeter array.

Ther have been a number of threads here on this topic with these speakers. The consensus is that it isn't worth the effort to biwire.

Using the current or voltage post of your amp is totally unrelated to the LSi25 speaker post design.

Herw is the recently resurrected thread on this particular subject of biamp/biwiring the 25s. Have a good read........

http://www.polkaudio.com/forums/showthread.php?t=4641

unc2701

Dennis is totally correct, and I should add that you probably want to use the voltage posts. Current source will sound wrong on just about 99% of the speakers out there.

Zen Dragon

From the Sunfire manual:
"According to your musical taste,
you may select the Current Source for
driving elec tro stat ic, pla nar mag net ic
or ribbon speakers. Se lect the Voltage
Source for driving sub woof ers.
For cone based sys tems, use either.
For a biwired system, use the Current
Source for midrange and treble drivers,
and use the Voltage Source for
the subwoofer(s). These are suggestions
only. By all means, please feel
free to ex per i ment with other wiring
options. (See page 14.)"
"NOTE: The Current Source output
is a Voltage Source modifed to yield
an impedance of one ohm. This corre
sponds ap prox i mate ly to a vacuum
tube ampli

unc2701

Ahhhh, so that's a little different from a true current source amp- Like the Nelson Pass F1

Dennis Gardner

Typical Bob Carver engineering. He has always built his amps on unconventional platforms, tweaking current/voltage delivery, and power supply switching etc. to achieve the voicing characteristics that he wanted.
Underappreciated in the least, bordering on genious at times.

Sthrndream

OK so I guess I have them biwired correctly. Im using 14 AWG wire (two sts) one to the tweets (upper) and one to the subs (lower). So now back to the original question in each of my posts.....lol...

THese cables that are out there, Im thinking of getting 10 Awg wire and making cables as opposed to buying Monster 2.4s because I dont know if there would be a sonic difference. Has anyone made their own cable and would like to share a recipe? Or am I better off looking for a biwire cable that has 4 inputs on each end for my Sunfire amp and polk lsi speaker.

I apologize for not being thorough enough each time I post. I assume (bad word, as Im in the Air Force) you guys know all about Sunfire etc. I really do appreciate the advice here. Im learning day in and day out!

Zen Dragon

Sorry Sthrndream:
Sort of got caught up in the design there. Based on the fact you obviously laid a little green out for a very fine amplifier I would recommend going with some good cables. Different people have dofferent perceptions of what they hear with different cables. Will you get a solid, well amplified signal using 10AWG wire....yes.
The question boils down to how much difference can you hear. There is obviously a difference in the engineering and measured response of a high end cable vs using bare copper wire. Some can hear it more than others. The arguable point comes in where you looking at cables that cost several hundred, or even iton the thousands of dollars.
Again based on the quality of your equipment, it seems you should match it with quality signal carrying cables. They don't have to break the bank, but a Sunfire amp surely deserves more than some 10 AWG electrical wire.
Just my opinion.
Good luck and enjoy.

F1nut

Sthrndream wrote:

OK so I guess I have them biwired correctly. Im using 14 AWG wire (two sts) one to the tweets (upper) and one to the subs (lower). So now back to the original question in each of my posts.....lol...

THese cables that are out there, Im thinking of getting 10 Awg wire and making cables as opposed to buying Monster 2.4s because I dont know if there would be a sonic difference. Has anyone made their own cable and would like to share a recipe? Or am I better off looking for a biwire cable that has 4 inputs on each end for my Sunfire amp and polk lsi speaker.

Edit: as not to confuse anyone. Thanks Dennis.

You say in your first post that you are using 12 gauge wire, then you say you are using 14 gauge wire, which is it? If you are already using 12 gauge wire you're not going to notice a difference going to 10 gauge, you might notice a little change going from 14 to 10...maybe. Personally, I've found bi-wiring is a waste. You'd be better off buying some nice high quality (not Monster) single run speaker cable and replacing the stock jumpers with the same type wire that you use for the speaker cables.

Dennis Gardner

The bottom posts on the 25s are only hi level powered sub inputs.

The top posts are mid/tweet combo posts.

F1nut

You know what, after study the connection drawings a little closer, I believe you are correct. Sorry for the confusion.

Sthrndream

Not to add to the confusion but I believe after studying the LSI 25 manual, I am technically Bi Amping the speakers not Bi wiring them. Also, based on the post referencing the Sunfire manual. Im using 14 guage not 12 guage.

Geez this stuff is so confusing.

Zen Dragon

Sthrndream:
I did not see any reference in the manual as to wire gage recommendations. I may have missed it. However your amplifier is capable of driving 800 watts RMS into the 4 ohm load of the LSI25's at high volume. Your peak power would likely exceed 1000 watts.
The specs in the manual list your max current output as 120 Amps peak to peak. This equates to just over 42 amps RMS at max power. With this current draw 10AWG is the minimum size wire you should go with and you might want to consider 8 AWG.
If you are running the two sets of wire out i would still suggest going to at least 12AWG

Sthrndream

Zen,

Thats very interesting! Thanks for the input!!