Search found 36 matches

by 2Bexperienced
Thu Jul 21, 2022 4:45 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I've been running the unit as a passive pre and there is plenty of gain even for phono. So I'm going to redo it as a fully passive. Since there is no AC chord to the unit I guess I just run my grounds to the enclosure?
by 2Bexperienced
Mon Jul 18, 2022 4:26 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK will do. Thanks for your help.
by 2Bexperienced
Mon Jul 18, 2022 2:29 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

I moved the AC outlet ground from the star to the lug on the enclosure and attached the chassis point to that. I moved the negative outlets on the output board from the star ground to the ground on the rcas. Still no hum or signal. I'm thinking there may be a problem with the way the pins have been ...
by 2Bexperienced
Sun Jul 17, 2022 3:21 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK trying to understand why you wrote GND on the
schematic you marked up. I am starting to understand that ground is a relative term related to voltage difference, but have no idea when to utilize absolute(earth) ground or a relative (signal?/audio?) ground and if there are guidelines.
by 2Bexperienced
Sun Jul 17, 2022 12:09 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I created a small loop on the shield pad at the input of the output board and tied pins 5 and 7 to that then tied what were the negative outputs to earth ground. I have totally eliminated the AC hum unfortunately there is no sound at all. Do I need to disconnect the pad on the power supply mar...
by 2Bexperienced
Sat Jul 16, 2022 11:21 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK so don't cut the trace? You have used 2 terms signal ground and audio ground. Is one or both of these a floating ground or do they tie to earth ground.
by 2Bexperienced
Sat Jul 16, 2022 9:35 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

So the connection from pin 5 to 8 is that additional to or instead of the connection that leads from 5 to output cause I dont see another way to make that disconnection from 5 to output other than cutting the trace
by 2Bexperienced
Sat Jul 16, 2022 8:01 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, thanks for your continuing help. In the schematic you have marked shows what was formerly L- output is now GND so my assumption is I run this to my star (earth) ground. Pin 7 I can connect to via the L- input pad on the output board. What is confusing me now is the connection between pin 5 and...
by 2Bexperienced
Sat Jul 16, 2022 3:43 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK, hence the title of the thread, What are all these different grounds? GRD, earth ground, signal ground, audio ground, and common. As a guy who only solders kits together its a little confusing. I realize guys may want the newbies to pay their dues but my understanding is so basic that discussions...
by 2Bexperienced
Fri Jul 15, 2022 8:40 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

No CT on the power supply which comes off a LL1683.
by 2Bexperienced
Fri Jul 15, 2022 4:24 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK for clarity, I run 5 and 7 to earth. What about the point labeled chassis on the power supply. I have tied that to earth and I see that it connects to the central tap which is not supposed to be grounded. What am I supposed to do with a point that has a common ground symbol like chassis as oppose...
by 2Bexperienced
Fri Jul 15, 2022 1:47 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

DD power supply.jpg Dave, I looked at my switch wiring and that seems to be correct. All I'm left with is that somehow AC current is affecting the signal. There were five yellow wires running from the main board to the output board. Per your instructions I removed the Negative leads for both the ri...
by 2Bexperienced
Wed Jul 13, 2022 4:23 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I got the autoformers hooked up last night and the passive side sounds great with plenty of gain, but the active side is nothing but a loud AC hum no signal at all, so I obviously did something wrong. I'll have to figure that out.
by 2Bexperienced
Tue Jul 12, 2022 11:42 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

I was going through some old emails from John and Dave and I saw where they had changed some of the resistors on the input side to allow for the TVC. Is the AVC of similiar resistance that a swap between the two is possible without modification?
by 2Bexperienced
Sun Jul 10, 2022 8:32 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

I just read through the instructions from the old TVC and it said to have the TVCs on the input side so that's what Ill do. I had assumed it was on the output side and was questioning why my switch seemed to be wired for the input. It makes sense now. Thanks
by 2Bexperienced
Sun Jul 10, 2022 6:07 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave should the AVC be on the input side or the output side of the active stage? After seems logical.
by 2Bexperienced
Sun Jul 03, 2022 12:41 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Thanks for your help Dave. I'll test it when I return from vacation next week.
by 2Bexperienced
Thu Jun 30, 2022 4:32 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

OK, I cut the yellow R- and L- inputs and black R- and L- outputs. So do I ground both my rca inputs and outputs to the star ground?
by 2Bexperienced
Wed Jun 29, 2022 4:37 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Are those the connections? Are the pin numbers in the same location as on the transformer sec sheet?
by 2Bexperienced
Wed Jun 29, 2022 4:34 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

36ac3737-ba5f-443d-bf22-abd8e6b0a1a0.png
36ac3737-ba5f-443d-bf22-abd8e6b0a1a0.png (71.26 KiB) Viewed 14361 times
by 2Bexperienced
Wed Jun 29, 2022 3:22 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, if you look at the photo I believe they are those large black slug like objects that are wrapped in wire ties. In the photo they are below the transformers on the same board.
by 2Bexperienced
Wed Jun 29, 2022 2:38 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Ok do you recommend slicing the traces on the board to make the disconnections you refer to?
by 2Bexperienced
Wed Jun 29, 2022 1:38 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

1674.pdf
(21.47 KiB) Downloaded 135 times
by 2Bexperienced
Wed Jun 29, 2022 1:35 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I'm looking at the pin layout on the schematic and the pin layout on the LL1674 spec sheet and they don't seem to correspond.
by 2Bexperienced
Tue Jun 28, 2022 1:47 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I'm thinking that it's a little crazy to have a balanced circuit and not take sdvantage of it. Maybe I should get two stereo attenuators and set it up with a mix of balanced and unbalanced inputs and outputs. I've already ordered a 4 pole selector.
by 2Bexperienced
Tue Jun 28, 2022 12:54 am
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

So Dave if I run a test and just use the plus signal on the board as the signal leg to and from the rca's what do I use for the rca ground? chassis ground? do I ground both the inputs and outputs to chassis ground?
by 2Bexperienced
Mon Jun 27, 2022 3:16 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave, I'm 100% sure those are S&B units. You can check the photo. The unit did "function" sort of but one channel was very noisy due to my own ineptitude when assembling.. I am buying a new enclosure and the plan is to mount them in the back with shaft extenders.
by 2Bexperienced
Sun Jun 26, 2022 11:25 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

Dave just for clarity I'm not going to be using any of the BentAudio equipment.
by 2Bexperienced
Sun Jun 26, 2022 11:21 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

I guess the only way to run it would be to hook it up with just the positve leads from each channel and not sure what to do for the ground on the rcas . but I could run it out to my Truth resistive passive preamp.
by 2Bexperienced
Sun Jun 26, 2022 10:03 pm
Forum: Circuits
Topic: When and where to ground
Replies: 54
Views: 60489

Re: When and where to ground

That's a good question Dave. There are wires connected to both the plus and minus connections of both channels on the board as well as connections to ground. So maybe it was running balanced and the Bent Audio input/output boards eliminated the negative signal. I remember John Chapman telling me tha...