How do I pay?

Escrow, or COD and inspection upon arrival, if not, then no No deal! That is a gentlemans agreement. Shipping is the only thing lost...

I had a guy show me one speaker twice, the other speaker was a hatchet job... He thought he was clever.. Be aware... He had them loaded on my truck.. when I noticed all kinds of things on ONE speaker.  It had been dropped... I was hoppin', I mean HOPPIN'...MAD... His next door neighbor was laughing his self into an attack.. I caught on real quick...

Out comes the pepper spray. :-)

Regards

Another don't do it. You send cashier check, he ships speakers, they get damaged in transit (speakers & heavy amps take the biggest hits in shipping). You think he'll take them back? 
 Paypal payment,  seller is responsible for delivering item as described.

Unless I could listen to the speakers in person, I wouldn't consider sending a cashier's check to somebody prior to having the speakers in my possession. And, $4K isn't something that would warrant such demands.
From my days of buying/selling watches, I have seen numerous posts about cashier's checks being bounced, as well as wire transfers. 
Unfortunately, we live in a world where a few bad actors spoil online buying, so I guess the seller is trying to protect himself.
One possible course of action is to ask if he has an Ebay, USAM, or Audiogon account, and you would be able to see if he has positive feedback.
B

See how trustworthy humans are. Who do you really trust? Why are we like this. Is i that there are too many thieves out there or are we all thieves under certain circumstances. 

@kjohn1234,

You can use Escrow.com to complete the sale. There is a small fee involved but atleast this gives you peace of mind against any possible fraud or defective merchandise. 

https://www.escrow.com/learn-more/how-escrow-payments-work/how-escrow-payments-work

If seller refuses to accept payment via escrow, I would walk away from this deal.