JBL 4365 Is SET Amplification Appropriate?

[Neonknight]

Have a pair of JBL 4365 that I have owned for a number of years. Typically I have used SS amplification on them and currently have a pair of AVM Audio Amp Essential monoblocks on them.

However, I have been a tube user for a long long time. I spent over a decade using SET amps, but found that these speakers did not care for a 300B based amp I had at all.

The question is, will these speakers work well with higher powered SET amplification, amps with 845, 211, or 572 tubes? From searching I have done there is no consensus about the compatibility of this kind of pairing. A person cannot just run downtown and grab a pair of 211 based amps. Some feel the JBL woofer does not respond to well to tubes in general, but if it had to be done it would be with a higher powered push pull design. Others say SET will work if the output transformers can pass enough current without saturation. Another group says don't bother stick with SS.

So I thought I would talk with the JBL crowd and get your thoughts and experiences with these speakers and drivers.

So please chime in and let me what you know. Thanks in advance!

[Ian Mackenzie]

The simple answer is moving to a SET valve amp as mentioned will be a trade off with too many compromises with your 4365’s. These monitors @93 dB sensitivity and required significant power 300+ watts to deliver the dynamic range required.

If you had Lowthers then go for it.

If you want the sweetness of a SET and have deep pockets consider Ampzilla or one of Pass Labs X350.8 power amplifiers. Some of the larger Macintosh power amps are also popular with JBL users.

https://www.sst.audio/ampzilla-1

[rusty jefferson]

SET amplifiers have high output impedance and pretty much all recent JBL speakers want to see an amplifier with low output impedance to better control the speaker.

Instead of compromising performance with an SET amplifier, you could consider a dac (assuming you're in the digital domain) with a tube output stage like the Lampizator brand. They were designed with horn speakers in mind and are very smooth sounding without adding the compromises that are inherent to SET amplifiers. You could also try different analogue and digital cables. Duelund analogue interconnect cables are quite smooth sounding also without being restrictive and are reasonably priced.