Larry Style Express

[Joe6v6]

After running across these "Larry" amps & finding some of the detailed photos I took the time to make myself a layout and went down the road of building a TW Express in a similar style. I learned a lot along the way but this amp turned out fantastic. Works as it should and has all the hall marks of a great Express. Initially I had traditional AC heater wiring but could not get a humm out of it no matter how I routed the wires so I incorporated DC heaters on the preamp tubes & it solved that. One of the quietist Express amps Ive built. Some photos below. I hope im not posting in the wrong area but I know a lot of people on this site are interested in this type of thing. .

 

[Music&Chaos]

That's awesome!!!

 

[chumbucket]

After running across these "Larry" amps & finding some of the detailed photos I took the time to make myself a layout and went down the road of building a TW Express in a similar style. I learned a lot along the way but this amp turned out fantastic. Works as it should and has all the hall marks of a great Express. Initially I had traditional AC heater wiring but could not get a humm out of it no matter how I routed the wires so I incorporated DC heaters on the preamp tubes & it solved that. One of the quietist Express amps Ive built. Some photos below. I hope im not posting in the wrong area but I know a lot of people on this site are interested in this type of thing. .

So, you gotta post some clips of the amp dude. Don't leave us hanging.

 

[Joe6v6]

So, you gotta post some clips of the amp dude. Don't leave us hanging.

If I can put something worthy together I will. The amp does what its supposed to, Me not so much. LOL. But I have friends who can really show what it does. I dont have much in the way of recording equpt. so we'll see.

 

[japetus]

@novosibir may like this!

 

[thegame]

You do realize that Express in business terms means fast service, right?

 

[bennyslo]

Absolutely epic work my friend. What I would give to have the time and know how to build something like this. I would love to play this, bet it it sounds quality. Does Larry's version differ much from the original TW designs? From what I can see of Larry's amps, his work is impeccable quality.

 

[FourT6and2]

Nice job!

For next time:
https://www.mouser.com/ProductDetail/RECOM-Power/RAC20-12SK?qs=qSfuJ%2Bfl/d5yjdCY3Xq18w==

 

[novosibir]

Does Larry's version differ much from the original TW designs? From what I can see of Larry's amps, his work is impeccable quality.

No, it doesn't differ much:
I haven't changed the orig. circuit, just a few part's values.
Then I've used ERO/Roederstein and Vishay MKT Polyester foil caps, which match the Orange 6PS foil caps Ken has used in their characteristic.
And I've used Beyschlag metal film resistors, which match the carbon film resistors Ken has used in their characteristic, but are less noisy.

But I've changed/upgraded the circuit's layout and have moved the preamp tube's filter caps close to the corresponding preamp tube's circuits, to avoid that interferences can ride on the long supply voltage's cables, where they are fed in the tubes.

And I've implemented a stabilized 12VDC preamp tube heater's voltage supply, to reduce background noise:

I've extended the circuit with an 'dynamic switch', seen next to the 2nd preamp tube, which reduces some of the anyway way too much gain, but results in an extended band width with more lows, nicer sparkling highs and slightly scooped mids:

As you can see I've used a much stronger chassis compared to the originals, made of 2 mm thick aircraft aluminum, to avoid chassis' damages due to the heavy transformers, as it happened with the original, when someone has rudely handled or by accident has dropped the amp:

I didn't close the entire chassis from below with a sheet metal like the original, but only mounted a shielding plate with stand offs over the sensitive area of the circuit:

I've used Transformers from the same supplier, where Ken has his transformers made, from Pacific Transformers in Anaheim/CA made spot on after Ken's specs with the exception, that they extended the primary for wall voltages of 120V and 240V as usual in Europe - and they put after my demand an additional 15 volts secondary on the PT, which I needed for the stabilized DC preamp tube's heater:

As tubes I chose what Ken had highly recommended as the optimal combination with his circuit - NOS Tungsram ECC83 preamp tubes and NOS RFT (Siemens) EL34 power tubes:

My Wrecky amps are equipped with a 2 mm thick front panel made of brushed brass, in which the lettering is engraved with milling cutters and then burnished.
So you can still read the lettering of the controls in 1,000 years without any problems

And my Wrecky amps also got a rear panel. This is made of 1 mm thick brushed stainless steel and the lettering is done with laser:

But there is no choice of the head shells, because I make them exclusively from curly maple:

As you can see only minimal differences to the original, only the workmanship and the layout upgraded a bit

 

[CrystalSky]

No, it doesn't differ much:
I haven't changed the orig. circuit, just a few part's values.
Then I've used ERO/Roederstein and Vishay MKT Polyester foil caps, which match the Orange 6PS foil caps Ken has used in their characteristic.
And I've used Beyschlag metal film resistors, which match the carbon film resistors Ken has used in their characteristic, but are less noisy.

But I've changed/upgraded the circuit's layout and have moved the preamp tube's filter caps close to the corresponding preamp tube's circuits, to avoid that interferences can ride on the long supply voltage's cables, where they are fed in the tubes.

And I've implemented a stabilized 12VDC preamp tube heater's voltage supply, to reduce background noise:


View attachment 450131


I've extended the circuit with an 'dynamic switch', seen next to the 2nd preamp tube, which reduces some of the anyway way too much gain, but results in an extended band width with more lows, nicer sparkling highs and slightly scooped mids:


View attachment 450132


As you can see I've used a much stronger chassis compared to the originals, made of 2 mm thick aircraft aluminum, to avoid chassis' damages due to the heavy transformers, as it happened with the original, when someone has rudely handled or by accident has dropped the amp:


View attachment 450133


I didn't close the entire chassis from below with a sheet metal like the original, but only mounted a shielding plate with stand offs over the sensitive area of the circuit:


View attachment 450143


I've used Transformers from the same supplier, where Ken has his transformers made, from Pacific Transformers in Anaheim/CA made spot on after Ken's specs with the exception, that they extended the primary for wall voltages of 120V and 240V as usual in Europe - and they put after my demand an additional 15 volts secondary on the PT, which I needed for the stabilized DC preamp tube's heater:


View attachment 450135


As tubes I chose what Ken had highly recommended as the optimal combination with his circuit - NOS Tungsram ECC83 preamp tubes and NOS RFT (Siemens) EL34 power tubes:


View attachment 450136


My Wrecky amps are equipped with a 2 mm thick front panel made of brushed brass, in which the lettering is engraved with milling cutters and then burnished.
So you can still read the lettering of the controls in 1,000 years without any problems


View attachment 450137


And my Wrecky amps also got a rear panel. This is made of 1 mm thick brushed stainless steel and the lettering is done with laser:


View attachment 450138


But there is no choice of the head shells, because I make them exclusively from curly maple:


View attachment 450145


As you can see only minimal differences to the original, only the workmanship and the layout upgraded a bit

Cool to see you share info

 

[311boogieman]

After running across these "Larry" amps & finding some of the detailed photos I took the time to make myself a layout and went down the road of building a TW Express in a similar style. I learned a lot along the way but this amp turned out fantastic. Works as it should and has all the hall marks of a great Express. Initially I had traditional AC heater wiring but could not get a humm out of it no matter how I routed the wires so I incorporated DC heaters on the preamp tubes & it solved that. One of the quietist Express amps Ive built. Some photos below. I hope im not posting in the wrong area but I know a lot of people on this site are interested in this type of thing. .

Welome to R-T and thanks for sharing. Nice work