Need help connecting Kaiju Monoblocks to Pre-Amp and Speakers

[Jimb0]

Hello. I built a pair of Kaiju 300B monoblocks and a single BeePre2 preamp. I will be using them with JBL L82 Classic MKII speakers.

Since this is my first time using monoblocks, I want to ensure that I connect them properly to avoid any damage.

Am I correct that I will need two RCA Y-splitter 2 male to 1 male cables to connect between each monoblock and preamp? Each Kaiju amp will connect as follows:
- The two male will connect to one Kaiju amp, and the single male end will connect to the left input on the BeePre2.
- The other two male will connect to the second Kaiju amp, and the single male end will connect to the right input on the BeePre2.

I need guidance connecting the Kaiju to the speakers. What cable should I be using and how do I connect them from amp to speaker?

Thanks in advance.

[Paul Joppa]

(I am assuming you have wired the output transformers for 8 ohm speakers initially.)

In the Quick-Start Guide for the JBLs, there are 3 ways illustrated to connect the amps to the speakers. The simplest would be to use the Bi-Amp connection, so that one channel drives the woofer and the other drives the tweeter. For this, you would use the interconnects as you described, with two speaker cables to each speaker (four cables total).

Each Kaiju is itself a stereo amp of 8 watts per channel, and you can use the 2-Wire connection to listen to that amp alone. Use regular RCA-to-RCA interconnects between BeePre and Kaiju. This might be useful to confirm correct operation of the amps, for example.

To use either the 2-Wire connection or the Bi-Wire connection with the full 16 watts power, you will need to re-wire the outputs to convert each amp to monobloc form. This involves re-wiring the output transformers to 4 ohms, and then connecting the outputs in series, which will result in a single 8-ohm output.

[Jimb0]

Paul, thank you very much for your reply. Yes, the output transformers were wired to 8 ohms. I would like to use 16 watts per channel so I will rewire it accordingly. Regarding rewiring the outputs in series, should I simply follow the Monoblock Conversion instructions on page 72 of the manual?

In a few days once I have it all connected I hope can circle back with you just to verify I have it all wired correctly.

[Jimb0]

Hi Paul. With the Bi-Amp connection, is the 16 watts being delivered to the speaker? 8 to the woofer plus 8 to the tweeter?

[Paul Birkeland]

Hi Paul. With the Bi-Amp connection, is the 16 watts being delivered to the speaker? 8 to the woofer plus 8 to the tweeter?

When you biamp, you will achieve the same operating level as just using 8W per speaker.

[Paul Joppa]

.... Regarding rewiring the outputs in series, should I simply follow the Monoblock Conversion instructions on page 72 of the manual? ....

Yes, those are the correct instructions.

[Jimb0]

Thank you for the help Paul. Everything makes sense now. 

[Jimb0]

Out of curiosity, I have some follow up questions regarding the monoblock conversion. What is the purpose of the 60.4 ohm resistors at the binding posts that we'll be shorting and why are we removing the 60.4 ohm resistors at the posts where we'll be connecting the speaker leads?

[Paul Joppa]

The resistors provide a path to ground for the secondaries, so that the speaker wires can't build up an electrical charge (in the event of leaky capacitors or static - electricity). This is hardly ever a problem, but I don't like to leave voltages floating or undefined. We use two per channel for a kind of balanced output. With monobloc wiring, only one pair is needed.

[Jimb0]

Thank you for the info Paul!