All those preamp switches

[Fischerman]

I noticed that some (like the ODS-101 schematics) omit the Rock/Jazz switch and it looks like the D'lite omits the Rock/Jazz, Deep, and Mid boost switches leaving only the PAB and Bright switches. I don't really have enough room for all the switches and I'm trying to decide which one(s) to omit.

So my main questions are: when using an HRM preamp which switches (if any) do you typically never use? Do you ever play the OD channel with the Deep switch engaged? Mid boost? Do you tend to always play the OD channel with the PAB ON...or OFF?

Would the simplified D'Lite tone stack work OK for an HRM preamp or are the Deep and midboost switches/circuitry required to make it sound right?

Thanks.

[Sven]

Greetings,

Well, if I am right, when one is using relay switching of PAB and OD (and that is very needed for real live playoing of this amp), than those mini toggle switches are basically only functioning as on and off switches to supply power to the relays, which means they are relay of-off switches of OD and PAB. That is how I see it in the layouts here displayed.

Well, in case you have relay switching (and, again, you really need it), you can either not install those switches anyway, or you could perhaps put them on the back panel (although it is not certain how the wires and the entire relay installation located between the board and pots, would influence the rest of the circuits?). But, some people have put those switches at the back panel, as I recall seeing some info on this forum.

So, you would have those Front panel switches free for what you might need more, such as mid boost (which some people also put on relay, which is a smart thing to do).

Sven

[Fischerman]

Thanks Sven.

In addition to the footswitching (Channel and PAB) I plan to use a pull-pot for the channel switching on the front panel. I actually have room or could make room for all the switches (I could use more pull-pots too) but I'm trying to keep the front panel reasonably simple...and I hate having useless switches/controls on an amp. The more I think about it the more I think I just need to dig in and experiment with it...this IS a prototype.

[odourboy]

Based on my own (albeit, limited) experience with an HRM d-clone, I've found I could do without:
1) Rock/Jazz - messed with it initially but now it just stays on Rock
2) Deep - messed with it initially but now it stays off
3) Brite - I generally don't use this either and I think a good alternative would be to hardwire a brite cap to your liking and just leave it.

I've set up a two-button footswitch so that the OD/PAB are tied to a single button. I use the second for mid-boost (which I use on both with both clean and OD). These are my own personal preferences. I'm sure others would prefer a different set up. YMMV.

Side note: I also had concerns about room and put the Brite on the a push/pull volume pot and the OD on a push/pull master pot. Obviously not your 'standard' Dumble control layout but pretty typical of many amps.

I noticed that some (like the ODS-101 schematics) omit the Rock/Jazz switch and it looks like the D'lite omits the Rock/Jazz, Deep, and Mid boost switches leaving only the PAB and Bright switches. I don't really have enough room for all the switches and I'm trying to decide which one(s) to omit.

So my main questions are: when using an HRM preamp which switches (if any) do you typically never use? Do you ever play the OD channel with the Deep switch engaged? Mid boost? Do you tend to always play the OD channel with the PAB ON...or OFF?

Would the simplified D'Lite tone stack work OK for an HRM preamp or are the Deep and midboost switches/circuitry required to make it sound right?

Thanks.

[Bob-I]

I used the channel switch, boost and mid boost only. On one amp (sold) I put all 3 on footswitches, the current owner uses all 3 switches.

[Tonegeek]

I combined PAB and Mid Boost on one footswitch and have OD on another.
The third footswitch is secret military stuff from area 51
Don't use DEEP, Rock/Jazz
Occasionally use Bright

If you have never built one of these amps it is tough to figure out what switches you will need. Try to make your design flexible enough to rewire a switch function if something does not suit you down the road. FWIW, some of my labels do not reflect what the associated switches are now doing. I just could not anticipate where this tone search was going to lead me. (Or maybe there is just no pleasing some people )

[Funkalicousgroove]

I find that the r/j switch is really useless, but I do use the Mid and Bright.

If you build an HRM you can hard wire your bright cap for the clean across the master if you're looking to save real estate.

[heisthl]

You don't need any switches except maybe the bright (use a 120pf) = put the Mid Boost on a relay and have a 3 button footswitch - OD,MID,PAB. Wire it so PAB always comes on with the OD but lets you use PAB without OD. Layout the footswitch so your foot can press Mid and OD at the same time. Place the footswitch on top of your amp if you miss the panel switches. If you're going to do Jazz gigs with a big body guitar you will want a Deep switch at a minimum and probably both Deep and Rock/Jazz would possibly be even better(I've never tried it) But one thing I have tried for soft Jazz is Deep on and an off position for the presence(it disconnects the feedback resistor) and it makes for an incredible full range smooth clean tone. If you're doing covers,rock,blues,fusion or country you don't need any of that stuff.

[mlp-mx6]

I like Bright only on the clean tone. This is handled via relay also. (engage OD, break the bright connection)

I have OD, PAB, and mid-boost on my footswitch and it is COOL!

I have one of the front panel switches choosing my mid cap (.01 vs. .047) - kinda the single-coil/humbucker switch.

[Fischerman]

Thanks for the responses. I had planned (tentatively) to make it compatible with a 'standard' 2-button footswitch (1/4" stereo jack) and wasn't even sure what to put there since, as I understand it, OD is always used with PAB (when HRM)...and I'm not sure how much I'd use PAB with clean.

[JimiB]

I like Bright only on the clean tone. This is handled via relay also. (engage OD, break the bright connection)

Were you able to do that with a single relay?

[mlp-mx6]

No, I used a second relay (SPDT) for that function.