[painkiller]

I have come to a conclusion on my bass system. I will use the Tone Tubby Superboy 15" driver with open back in a 32"Hx27"Wx20"D pyramidical horn. This combination simulated pretty flat from 80Hz to 600Hz in Hornresp, with an overall SPL of 100dB. Filling in downwards from 80Hz should be easy.

The system will be pretty huge in the end, and it will end up as a cross between an OB and a horn speaker. 

[Graham Maynard]

Hi painkiller,

If you are going to 20" depth with a horn and up to 600Hz you are likely to hear it.
Frequency responses do not tell you what shapes sound like.
Try a quick mock-up first.

Cheers ....... Graham.

[baMarek]

Hi Graham,

After weeks of testing I have to confess I have a problem with t-bass. It boosts the lower section but the highs lose their clarity and power. When I play with the transformer on one side only I can very clearly hear the highs on t-bass side are much inferior to the side without the circuit, both volume and quality wise. I checked 2 different amps and the situation is the same. Bi-wiring did not help.
Do you have any idea what may be wrong?

Thanks,
Marek

[PB]

Hi baMarek,
Do you use just one amp? I think most of the users of T-bass are bi-amped or more?
I don't claim any knowledge about this, just merely curious as I have gotten some transformers and will try soon...

Sadly, the secondary coils measure ~1 ohm but it could be the crappy multimeter I have also. It is not measuring correct at these low resistances, hopefully...

Peter

[T-BAG]

PB,
Neither of mine measure too well either on low resistance. I think adding a 5 ohm resistor or so in series first may reveal there true impedence, but I am no expert. I just went with the default 1ohm resistors.
I plugged it in kind of freewire with roach-clips the other day to one channel and certainly recognized the bass boost.
Mine are crossed at 12db at 200hz, bi-amped, so I don't hear a lot of upper-bass maybe in mine either. But I will try a compairson.
I hope to get it all attached to a piece of wood soon so I can hook it up a bit easier. I imagine this sort of thing needs tweaking.

[baMarek]

Hi PB,

Yes, I have been using 1 amp. To get the biggest boost I completely got rid of resistors but with 1ohm the effect on HF was the same.

Re your low impedance, I am pretty sure this is the case for everyone using t-bass. No need to worry too much if it doesnt trigger any safety mechanism in your amp.

[PB]

Hi Marek,
:Re your low impedance, I am pretty sure this is the case for everyone using t-bass. No need to worry too much if it doesnt trigger any safety mechanism in your amp.:

Yeah, that's clear for me.  Only "concern" is Graham's advice to use windings preferably lower than 0.5 ohm.........

T-BAG, thanks, I will sure try. When I get time and inspiration

Peter