TG1 HPF & Attack Controls Question

[sine_wave]

The original TG12413 has a control for Recovery, Hold, Output and a switch for Comp/Out/Limit. In Fester's TG1 project, there are the aforementioned controls plus HPF (I think it's for sidechain) and Attack. Both functions are not faithful to the original TG units.
I'd prefer to leave those two out of my build. Problem is, I haven't heard from anyone that it is indeed possible to leave them out and if so, how? Grand Master Audio makes some incredible custom panels for diy projects. On his website I saw a few variations of TG1 panels he designed. What's interesting is that his panels do not have provisions for HPF or Attack which leads me to believe that some people must be building it like I would prefer to. Anyone here build it without the HPF and Attack?

Anyone with TG experience please chime in. Can I build it leaving the undesired controls unstuffed and have the rest function as it should? Or is there another way? I asked on the TG1 build thread at the diy-racked forum but it seems I have a better chance winning lottery than getting any answers at all over there.

 

[Biasrocks]

Yes, if you look at the schematic you'll see that you're able to duplicate the standard TG1 behavior. Setting the Attack to Auto (last position) mimics the original and then finding the appropriate release settings (six on the original) they're all there just compare the schematics. Leave the HPF in bypass and your done. Of course you'll have to do some custom wiring and mods to get it there.

Personally I find the additional functions useful, but I can understand why you'd want to stay closer to the original.

Make sure you get a set of OA202's and output transistors from Frank as they really put this project over the top.

Mark

 

[Rob Flinn]

Not difficult to leave out the HPF, but it is quite a useful feature IMHO, great when using the tG across a drum bus.

 

[briomusic]

ok, I'm gonna give this one a go....

I would recommend still connecting all the PCBs as some other needed functions are also on there (Comp In, for example).

To disable HPF: Leave out the HPF Rotary switch, instead connect A1 to A and C1 to C. This is the equivalent of having the HPF switch in the off position. You can leave out C101-110 (no jumpers just don't populate). Furthermore, the 5M resistors around the rotary switch are not required.

To disable Attack: Leave out the Attack Rotary switch, as well as the related resistors (they have no numbers, the ones surrounding the attack switch) you also don't need D16-18. you DO need C10 and you should hardwire the fast switch in the slow position, if I am not mistaken that means connecting the top and middle hole on the left and right side of this switch.  R47 should be 8k2 instead of 82k, since this is the value in the original. (I believe 82k was used by the good uncle to achieve a variety of values by switching additional resistors in parallel).

ETA after reading biasrocks post: in that case leave the diodes in and connect A to 11 where the Attack rotary switch was meant to sit.

just my 2 cents - I would think very hard about doing leaving these functions out. I almost NEVER have the HPF off on my TG1 and I am using all sorts of Attack values (including auto), depending on program material. Music has become a lot more bassy and 'transienty' since this compressor was designed.

 

[Biasrocks]

Also, the FAST/SLOW switch corresponds with LIMIT/COMP in the original.

Mark

 

[sine_wave]

Thanks guys. After reading this I'll most likely leave the HPF in. Briomusic, thanks for the incredibly helpful post. I'm sure it will come in handy.