Are you sure your interconnects and speaker cables are consistent with vertical bi-amping. I got better sound with the Aloi's at 30 watts than I did with bigger amps. Bi-amping increased the soundstage immensely.
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How are you running these amps ? Bi-amped ( vertical or horizontal ) or bridged ??? From the input that you've stated about power output per channel, i'm assuming bridged.
For sake of clarity and those that may not know the different terms, vertical biamping uses one stereo amp per speaker. Channel A runs the bass section of the speaker and channel B runs the mids and highs.
Horizontal uses one channel of each amp for the bass and the two channels of the other amp feed the highs.
Bridging takes the two channels of a stereo amp and converts them into one BIG channel. You then need two amps in order to make a stereo pair.
All three of these arrangements sound different even though your using two identical amps. Bridging typically gives the highest voltage levels possible out of the three different arrangements but usually results in a much harder and thinner sound. Sean
Sean and Snook2 I bridged each amp to form one big channel. Amps are bridgable. Gregm thaks for the tip, I will be sure to look it up. I should mention that, Classe did recommend Vertical biamp than the monoblocks. But need, Two sets of interconnects (same brand) with Y-splitter at the pre-amp. I bought extra pair of speaker cables same length, same brand. IC would be tricky, since I have to deal with y-splitter. Probably would inquire with the Straightwire tommorow. But I don't want spend extra $500-600 with same results, without proper feedback from Agoners. Thx.
p.s. Let me tell you that my current sound using only one CA-400 is GREAT, but sound stage depth improvement is desired-without moving the speakers!!
Nilthepill. I am no techo, but I think bridging ups the wattage but makes the speaker load look twice as difficult. So maybe the sound you are getting is what the Classe would sound like into a 2ohm load - could be, and no doubt someone will correct me if I am wrong - please be gentle?
I would be very tempted to peek inside the Classe and see if I could link together the hot connections on the left and right input RCAs without doing any real damage (or get someone competent to do it for you - possibly a better result than using Y connectors, and a darn sight cheaper than buying additional interconnects.
I don't know if your CA400s are also balanced or not, but I recently vertical bi-amped a pair of McCormack amps using RCA ICs, and I accidently switched one amp to the balanced mode and got sound like you describe.
Do the CA400s have balanced switching of some kind? Other than that, I would make sure all speaker cables are attached to the correct speaker and amp terminals for the way the monos need to work. Good Luck. Craig
Yo are on the right track except you strapped your amps mono. By bridging you increased output power hower reduced current from the amps thus losing some control of the speaker by the amplifier as now the amps see the load at half the previous impedance. In other words, If your speakers are a 4 ohm load, in bridged mode each amp sees a load of 2 ohms. This would account for the bright and hardness you now experience!
If you can biwire your speakers, remove the jumpers and do so. I am assuming that you have one long run of interconnect, and have the amps next to the speakers. If so, you'll find with a short run of speaker cable you can use almost anything! As to splitters, even a cheap pair of Rat Shack splitters will give you an idea of what is possible.
Use them on the amp end and then use one channel of each amp on the woofers, and the other channel of the amp on the tweeters. I can virtually guarantee this will result in improved sound!
Thx you all for your input. Garfish, Classe does have switch for mono/stereo operation as well as Balanced/RCA operation. Am running Balanced. Radio shake would have Y-splitter for balanced configuration? Will check it out. Redwiki, I don't know about opening the amp and bridging the RCA's( I am no techno either).
I think this is what I should do to go towards vertical bi-amping. Use the other pair of speaker cable and try out the biwiring with my existing STEREO amp. If the sound does not deteriorate, I try Vert biamping using radio shake y splitter. If works (meaning not deteriorate ) get the remaining pait of straightwire IC( Same as my existing brand, works great in my system) with straight wire Y-splitter at premap end and hope for best.
If not use the extra amp for (open a welding shop or something) my rear Dunlavy surrounds and just use he Multichannel Classe CAV-150 for cente channel only. Oh well! thx all.
Shame on me, I assumed you were using single-ended interconnects. Rat Shack will not have any balanced Y
adaptors. Tough call here. I still believe your sound will improve from biamping, however you will need balanced y connectors (not sure these are available) or a second run of balanced cable (if) your preamp has 2 sets of balanced outputs! Good luck!
Paul, you are correct about the load the amp sees. A strapped or monoed amp can produce a lot of distortion. Each channel of the stereo amp now just amplifies one half of the waveform. Lets say there was a channel imbalance between the channels and now the positive portion of the signal is not the same amplitude as the negative. This could amount to a lot of distortion in an amp with a channel imbalance.
I called Classe to day and asked for their opinion on the subject. " two much power for easy load speaker" they said. If I had hooked up to difficult load , it would have sounded better. Robert Adam re-iterated his recommendation if vertical bi-amping and swore (close) that I would get much better results than my current sound. So I am off to getting a new two pairs of same cable make with one pair out and two pairs in at the amp. Thx all for your support!!!!!
The best solution for you and your equipment is to bi-amp horizontally. The most obvious reason is the by doing this, (using one amp for the lows and one amp for the highs) it puts the least amount of stress on the amps by using both channels equally.I don't think that you will experience any negative sound affects. Overall, I think it will sound better.
On My quest for perfection, Over the week end I tried to Bi-wire my Dunlavy V's, with my 2- Classe CA 400 in monoblock configuration ( no vert or hor biamping yet) I DID everything right: Connect to the right terminal at both amp and speakers, Both amps in balanced/mono configuration, speaker jumper removed, using a seperate speaker cables( same make, same length) for bass and mid's. Here is what happened. The right speaker worked alright with the right monoblock. The left speaker made a lound sharp popping noise like little fire cracker! Scared shit, I disconnected the left speaker right away. Did some trouble shooting and put jumpers back on an ran single wired.Turned out that left amp channel fuses were blown on the left monoblock even though the channels were bridged. What might have happend? Do you think the mono switch on the left monoblock may not have engaged?