Josh's 18W Tremolo TMB Builds

[JMPGuitars]

Is there another puzzle session awaiting for the Xtra TMB... like you have put us through with the reverb enigma?

lol, not exactly. I haven't decided if I want to share it or not. I'm more likely to share it in PCB format because it will probably be an easier build that way. The Xtra TMB is an advanced build, and needs to have very good soldering and layout...and the reverb version is a little crowded.

[JMPGuitars]

JMPGuitars-TremTMBR-PCB-Complete.jpg

Here's the completed board with the foils marked. I also marked the schematic so anybody making either version knows which way they go.

Thanks,
Josh

[crgfrench]

Josh what are the overall board dimensions and hole mounting dimensions? I'll make some suggestions depending on what they fit.

[JMPGuitars]

Josh what are the overall board dimensions and hole mounting dimensions? I'll make some suggestions depending on what they fit.

The board is about 12.1" by 3.75". Holes are drilled for #6 screws.

[crgfrench]

Josh here are some immediate thoughts:
A good pricepoint for this board (bare) would be approx. $50 to $75, based on comps (obviously these are not circuit comps, just a sampling of some currently available PCBs out there for builders):
$10 Wattkins Big British Distortion PCB (9"x6")
$20 TubeDepot 5E3+ PCB (8.25"x3.125")
$29 Granger JMP/2203/2204 ST1 PCB (dimensions unknown)
$30 GAPCB Baby Will PCB (10"x3")
$35 GAPCB Plexi SE PCB (8"x4")
$45 Wattkins Universal PCB (9"x3.75")
$75 AA Electronics Dumble ODS PCB (13.6"x4.5")
$100 Ceriatone Son of Yeti PCB (11"x3.25")

This board would not fit in a Hoffman Stout chassis, but it would fit in a lot of others, such as:
Wattkins Universal Chassis (aluminum) $50
Weber 6M36CH-REVB (aluminum) $99
Ceriatone 36W aluminum chassis $75
Ceriatone Son of Yeti steel chassis $55
(...& a lot more I'm sure, these just popped to mind.)

[JMPGuitars]

Josh here are some immediate thoughts:
A good pricepoint for this board (bare) would be approx. $50 to $75, based on comps

Thanks for the feedback! I was thinking $50 would be a good price. Of course if you compare the quality/thickness of these boards to those others, $75 is better. lol But I'll probably do about $50 and then have a small discount for members of this site.

That's good to know about chassis for other people to use. I'll obviously continue to have my own made, and possibly have a kit version available with them.

I'm thinking about offering kits like this:

Option 1:
PCB only

Option 2:
PCB + Small parts kit including resistors, caps, etc...

Option 3:
PCB + Small parts kit + chassis / faceplates + all parts (including sockets), excluding transformers

Then maybe offer turrets and transformers separately as addons.


None of it matters until I've built out a couple of them for the 36W and 18W versions to make sure it sounds great either way. The 36W version I'm building is using turrets as pictured above, but the 18W version I build I'll skip the turrets except for maybe the ground connections.

I shouldn't mention this, but I had an idea for the next version of the board where I'll include a switchable .01µF cap in parallel with one of the others in the preamp to make the tremolo speed switchable. Obviously it can still be done point to point(ish) on this board. I'll probably do it on the 18W version to illustrate it.

Thanks,
Josh

[ViperDoc]

All looking quite nice!

I noticed a revision posted for the TMB Trem SCH. Value tweaks?

[JMPGuitars]

All looking quite nice!

I noticed a revision posted for the TMB Trem SCH. Value tweaks?

Thanks!

I dunno. I don't remember. If you mean the one I linked above with the foils, I think the only difference is the foils? It depends on which version you're comparing it too.

On my 36W PCB pictured above, I did make some changes to values, but they're all optional. I used a 220pF treble cap, I'll be using a 25K mid pot, and one of the .01µF trem preamp caps is .022µF to get slower trem speed. My combo sounded a little bright for my taste, so I'm making some small tweaks to see what I like.

[Bieworm]

All looking quite nice!

I noticed a revision posted for the TMB Trem SCH. Value tweaks?

Thanks!

I dunno. I don't remember. If you mean the one I linked above with the foils, I think the only difference is the foils? It depends on which version you're comparing it too.

On my 36W PCB pictured above, I did make some changes to values, but they're all optional. I used a 220pF treble cap, I'll be using a 25K mid pot, and one of the .01µF trem preamp caps is .022µF to get slower trem speed. My combo sounded a little bright for my taste, so I'm making some small tweaks to see what I like.

I can confirm the amp sounding bright. My 2nd tremolo TMB was rather bright too. The 1st was not. So I took that early 70s g12h30 from the 1st and swapped that one with the G12M65 Creamback that was in there. Overly brightness gone and nice creamy sounds on tap.
Fwiw, I think if you can find an emi 1228K the perfect marriage would be a fact.

[JMPGuitars]

I can confirm the amp sounding bright. My 2nd tremolo TMB was rather bright too. The 1st was not. So I took that early 70s g12h30 from the 1st and swapped that one with the G12M65 Creamback that was in there. Overly brightness gone and nice creamy sounds on tap.
Fwiw, I think if you can find an emi 1228K the perfect marriage would be a fact.

Yes, speaker has the biggest impact usually. But that's why I'm making small tweaks, because I'd rather stick with the speaker I'm using. It sounds amazing if I turn the treble down, so I'll adjust my build to suit.

I also prefer to use a 2x12 cab with only one speaker in it, so pairing a speaker doesn't work for me either.

[JMPGuitars]

My heater wiring is done. Here's my typical process.

First I measure out the heater wires.

JMPGuitars-Heater-Wiriing-1688.jpg

Then I strip them. This time I used a thermal stripper, and it works well, but my normal stripper works well on this gauge too.

JMPGuitars-Heater-Wiriing-1691.jpg

These PTFE wires are not pre bonded, so I tinned the tips.

JMPGuitars-Heater-Wiriing-1692.jpg

The wires are all tinned/bonded, and heatshrink is ready to go.

JMPGuitars-Heater-Wiriing-1696.jpg

First I make a mechanical connection, and solder in the leads. Then heat the shrink.

JMPGuitars-Heater-Wiriing-1708.jpg

Sometimes I use PVC instead of PTFE. They're both good. Here's the differences from my perspective:

PVC:
The PVC wire I get is fairly high temp, and pre-bonded. That's a big time saver. However, PVC doesn't hold its form as well, and is not nearly as heat resistant as PTFE. If you see some of my other heater wiring photos with PVC, you might notice I don't generally connect pin 9 on the preamp tubes until the end to avoid nicking the wire with the soldering iron. Pro tip.

PTFE:
PTFE wire is great, has very high temp resistance, and holds its form really well. It is more work though, and more expensive. Stripping PTFE is (sometimes) harder than PVC, and I have not found pre-bonded PTFE. Tinning/bonding is necessary prior to working with it. If you have good strippers, and a solder pot, it's not that big of a deal. If you don't, I would stick with PVC.

Thanks,
Josh

[Bieworm]

Very nice!!!
Is it 6V6 or EL34 winding up in the power section?
I'm confused Josh... did you prematurely solder pins 9???

[JMPGuitars]

Very nice!!!
Is it 6V6 or EL34 winding up in the power section?
I'm confused Josh... did you prematurely solder pins 9???

Thanks

EL34 for this one.

lol, not prematurely. The PTFE is fine to go first (at least for me ), it's higher heat resistance and thinner, so it's easier to deal with in that regard.

[TriodeLuvr]

PTFE wire is great, has very high temp resistance, and holds its form really well. It is more work though, and more expensive. Stripping PTFE is harder than PVC, and I have not found pre-bonded PTFE. Tinning/bonding is necessary prior to working with it. If you have good strippers, and a solder pot, it's not that big of a deal. If you don't, I would stick with PVC.

What does that mean, "pre-bonded"? And why do you tin it? All the PTFE I use is silver plated. Solder flows almost instantly throughout the joint. You're right about it being difficult to strip. I use thermal strippers for this, and I think I read that you do, too.

Jack

[crgfrench]

I use the silver plated 20G stranded copper insulated with PTFE. It strips just as easily as anything else, I use a Klein Katapult stripper. No need to pre-tin, it has the silver plating ready to solder. Wonderful stuff to work with. I did this heater line with it today.

Volcano Heater Wiring.JPG

[TriodeLuvr]

That's nice wiring! Where I used to work, we wired chassis with Tefzel almost exclusively. It has many of the properties of PTFE, but easier to strip and less susceptible to cold flow. Really nice to use, but unfortunately I don't have any for use at home.

Jack

[JMPGuitars]

What does that mean, "pre-bonded"? And why do you tin it? All the PTFE I use is silver plated. Solder flows almost instantly throughout the joint. You're right about it being difficult to strip. I use thermal strippers for this, and I think I read that you do, too.

Yes, it is pre-tinned and silver plated, but it is not pre-bonded. This means that the wire can fray, and doesn't hold it's form as well when manipulating the end. Pre-bonded means that the stranded wire gets soldered together during construction of the wire. Best practice for wire is to bond (solder) the ends of the wire prior to soldering in circuit.

I do have a thermal stripper, and it works well. However, with this gauge of wire, the Klein stripper also works perfectly well. I like the thermal stripper because it has a larger range than my other strippers (16 to 30AWG). In some case, the thermal stripper can also work a lot easier with shorter wire if restripping is needed.

[JMPGuitars]

I use the silver plated 20G stranded copper insulated with PTFE. It strips just as easily as anything else, I use a Klein Katapult stripper. No need to pre-tin, it has the silver plating ready to solder. Wonderful stuff to work with. I did this heater line with it today.

I think we both have the same stripper. It works great, but it's an issue sometimes for shorter wires, or different wire gauges. 20 and 18AWG PTFE both usually work fine on it.

Yes, as I mentioned above, same wire, but bonding is best practice for the ends of the wire to avoid frayed wire, and for holding form better prior to soldering. See my soldering video links.

Very nice heater wiring! I thought it was funny we both started posting heaters about the same time.

[crgfrench]

Very nice heater wiring! I thought it was funny we both started posting heaters about the same time.

Yours too! I was chuckling, I saw your post right after I finished mine -- great minds think alike...

[JMPGuitars]

Very nice heater wiring! I thought it was funny we both started posting heaters about the same time.

Yours too! I was chuckling, I saw your post right after I finished mine -- great minds think alike...

And we are pretty awesome.