Bass Amplification and 2x12" Cabinets - Suggestions

[roberto]

I built two bass amp for myself, both with tube preamp (one with a modded Baxandall, the other with Fender like eq) and class D poweramp, otherwise I've always used David Eden head&cabs. I've also built a TQWT 2x10" bass cab.

Now I've receipt the latest upgrade of this amp ( http://www.connexelectronic.com/documents/TA3020v4.pdf ) that has 1000W @ 4Ohm and 700W @ 8Ohm, and I'm gonna build my 3rd bass amp.

Let's start with the preamp:
I've always used the eq flat on Eden, and usually I don't eq too much the bass, except some 40Hz cut to add clarity and let the amp sound faster.
So I decided to start with a simple preamp with just a gain and a volume, cutting lows and highs to my tastes and fine tuning to the cab.

I've a 220k 2k7 first gain stage, a gain pot into a 220k 1k5 stage, then three dc coupled stages: a CF and a concertina.

The CF with the 47k cathode resistor is there to add the warmth tyical of the "half-wave rounding effect", then again dc coupled to a concertina phase inverter with the grid exactly at half the supply voltage to maximaze the headroom. (This preamp works very good with a pair or quad of EL84 as a guitar amp, if you want just add a selmer-like mid cut between first two stages and bypass caps)

Then instead of the 220k PI load, for the bass amp I'll use a 520k load: 470k from each side of the PI into a 50k log dual pot. This is not intended for PI saturation (I set it as clean), but for 2nd stage+CF saturation.


Now about the cab:
I'm planning to build a TL806 like 2x12" ( this is the 4x12, just cut in half http://hf-antenna.com/Flotsam/EV/Electr ... TL806Q.pdf ) cab with something like Eminence Kappa 12a speakers (similar thiele-small parameters to EV12L, nice presence around 1-3kHz). And this is the main question: do you have any experience about bass speakers in TL806 cabs?
Do you have any suggestion?

[rock_mumbles]

I would make it as a vertical cabinet as you'll be able to hear it better on stage (have better horizontal dispersion) ...

Sort of off topic ... but a friend just got one of the JHawk Dually cabinets with Faital drivers http://jhawkcustoms.com/gbdual.htm ... it's an amazing sounding cabinet. After playing at an outdoors concert his reply was that he could his bass everywhere on stage ...

[roberto]

I totally agree, also the other one I built was vertical, and angled too.
I've seen they suggest http://www.eminence.com/pdf/Kappalite_3012HO.pdf
Do you know something more about those cabs?

Just got into my mind that I suggested my modded baxandall on this forum time ago: https://tubeamparchive.com/viewtopic.php?t=9568

[Bear]

A doubled TL-806 should be similar to the Dr Z "Z-Best" cab. I've seen chatter that if you adjust the port tuning (the shelf length) and put in bass appropriate speakers that it works out well as a bass cab. If the info doesn't come up on search, maybe at TalkBass. (They tend to be a bit down on the EV thiele plans over there.)

[roberto]

Yes, I've read good impressions about Z-Cabs used with bass speakers too.
Also another italian builder (ATS) seems to use this configuration. And I absolutely like those cabs.

[roberto]

I've seen lots of people on talkbass suggesting fEARful cabs: http://greenboy.us/fEARful/ but Eminence Kappalite 3012LF are 260€ each and I need at least two ( http://greenboy.us/fEARful/DL/1212+6/ ) and that way it becomes too costy. I'll keep on searching TL806 and Eminence Delta Pro 12A informations.