Question about Bass

[El Tel]

Hi Everyone

I wonder if you could give me a little guidance  ?
I have a Moreplay Pre going into my Icon Audio 300B Amp and feeding a pair of Klipsch Forte Iii, and there seems to be a lack of bass with this setup compared to me connecting an old Harmon Kardon 20wpc amp that I have.
I've been reading up on various forums and some say that the 300b amps are all about mids and highs and rather thin on the bass side of things, and that a push pull and would get me more bass. With that in mind what would be your suggestion regarding me buying one of the Bottlehead kits ?
Which would be best for what I'm looking for ?
Many Thanks
Terry

[Paul Joppa]

I have not been able to find any Icon SE 300B amplifiers - only push-pull. Do you have more information?

[Paul Birkeland]

Which Icon 300B amp do you have?  All the ones I'm seeing from a quick search look like they are push-pull.  If you have the one with four 300Bs and four 6NS7s, that has the tube complement and output transformer size typical for a push-pull amp.

The Forte III has a few dips to around 4 ohms in the bass frequencies, so possibly using the 4 ohm taps could help even out the sound. How does the bottom end response change if you go from 0dB to 6dB of feedback on your amp?  Increasing feedback will reduce the tendency of the amp's output to wander as the speaker impedance changes. 

As far as 300Bs and no bass, there are definitely a lot of output transformers on the market for 300B amps that aren't so great on the bottom end.  Furthermore these amps have a lower damping factor and that can interact a bit with bass reflex boxes as well.

 

[El Tel]

Hi both Paul's and thanks for replying.
I think I have been misled on the info I have read because as you say my amp is a push-pull, sorry about that. It is the Stereo 300. MKI which has 4 x 300b, 2 x 6SN7 ans 2 x 12AT7's but it just seems to lack bass to my ears.
I'm wondering if I can find something better from your kits that would be better in the bass department?
I not sure what you mean by your 0db to 6db Paul, excuse my lack of knowledge 🤔.
I'll put a pic up of it if that OK.

[Paul Birkeland]

The manufacturer mentioned an adjustable feedback switch.

Something like the Kaiju will have fuller bass (in my opinion at least) than a 300B push-pull circuit due to the lower damping and extra bit of harmonic distortion that distinguishes SET amps from PP amps.