Bal. In/Out Buffer with H2.

[Samuel Jayaraj]

In my PA set up, I use a Presonus Digital Mixer. I find that the mix can sound very sharp and metallic compared to my analogue Soundcraft, for instance. However, the versatility of the digital mixer is addictive.

I was thinking that adding a balanced input/ouput buffer, capable of handling about 15 volts input/output without clipping and being able to arbitrarily set the amount of H2 would produce warmer sound in the final mix.

Any of the Pass designs which can be easily adapted for this application?

Thanks,

[Samuel Jayaraj]

Bump and thanks!

[Itsmee]

OK, it's not unity gain and its not balanced, start at Post 10854 in the F5 thread, it may give you some ideas.

Originally Posted by Nelson Pass

Easy enough to explore this with the F5. Just adjust P3 to get out of the 2nd harmonic null and take a listen.

[Samuel Jayaraj]

Thanks Itsmee for the pointer. However, I am looking for Line Level application and not a power amp. As of now, the front end of the BA-3 (balanced version) looks like the best bet, but I am not sure if it will handle 15 volts input/ouput, even if adjusted for unity gain??

Another candidate might be the BoSOZ! Any more pointers? Thanks.

[Zen Mod]

you can bet that F4 FE is made for that

[Samuel Jayaraj]

Thanks Zen Mod; very good suggestion. With the F4 Front End, it is possible to feed an unbalanced signal and derive a balanced signal at the output. (Although I prefer to have the input balanced, as well). Someone will say double up the circuit, I know. However, will the F4 Front End have a low enough output impedance? And is there someway of incorporating an adjustable H2 pot, as in the BA-3 Front End?

Since my 'Toshiba' (313 & 2013) supply from UTsource turned out to be fakes, is it possible to build the BA-3 Front End with IRF output devices, set the gain to unity and get a good amount of H2 to blunt the 'metalic' sound coming from the Presonus Digital Mixer?

Thanks.

[Zen Mod]

Originally Posted by Samuel Jayaraj

Thanks Zen Mod; very good suggestion. With the F4 Front End, it is possible to feed an unbalanced signal and derive a balanced signal at the output. (Although I prefer to have the input balanced, as well). Someone will say double up the circuit, I know. However, will the F4 Front End have a low enough output impedance? And is there someway of incorporating an adjustable H2 pot, as in the BA-3 Front End?

......

you're asking too much from simple approach ;

Originally Posted by Samuel Jayaraj

.....

Since my 'Toshiba' (313 & 2013) supply from UTsource turned out to be fakes, is it possible to build the BA-3 Front End with IRF output devices, set the gain to unity and get a good amount of H2 to blunt the 'metalic' sound coming from the Presonus Digital Mixer?

Thanks.

that's the way to go .

use Papa's balanced BA3 FE schm

[buzzforb]

Another suggestion would be OPA1632 Preamp with buffer in front and then you got SUSY. Check SUSY gainclone thread for idea. BA-3B will be driving a crippled F4 for me this weekend, so I'll let you know how it sounds.

[Samuel Jayaraj]

Thanks everyone. I'll go with the BA-3 Front End, Balanced version set to unity gain or thereabout. I'll experiment with IRF devices but got a gut feeling that the Toshibas would be better. I'll get them. buzzforb please check your PM. Thanks.