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New project Tremolux 6g9-b
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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Fri Jan 06, 2012 5:06 am    Post subject: New project Tremolux 6g9-b Reply with quote

A year or so ago I got stuck with an original AB763 Tremolux cab, and chassis went to another guy Embarassed

Well I am having a custom 21.25 x 7 x 1.75 slant chassis made to fit my new Tremolux faceplate I just received from Tube Amp Doctor.

I'm going to use one of my Hammond organ PTs and Mojotone fender replacement OT.

I had an original grey tolex cab AB763 with brown faceplate and cream knobs that I sold to Mike Keller now I can replace that amp finally.

Mark
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tubeswell



Joined: 27 Mar 2008
Posts: 1644
Location: Wellington. NZ

PostPosted: Fri Jan 06, 2012 5:40 am    Post subject: Reply with quote

Cool! I've always fancied building one of those.
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Last edited by tubeswell on Sun Jan 15, 2012 8:57 am; edited 1 time in total
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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Sun Jan 15, 2012 12:56 am    Post subject: Reply with quote

Received a custom chassis today ordered off ebay from Seaside Music for the Tremolux which is 21.25 x 7 x 1.75 chassis.

I maybe could have squeezed it to 7.25 or so but the chassis fits perfectly.

The Tremolux faceplate is available from www.tubeampdoctor.com The faceplate is brown it looks black in the second picture.

Next will be marking, drill, punching and drueling. Laughing

Mark
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Cliff Schecht



Joined: 30 Dec 2009
Posts: 2611
Location: Austin

PostPosted: Sun Jan 15, 2012 6:24 am    Post subject: Reply with quote

I've been thinking about building an EL84 Tremolux. I just put together a 2x12 cab with some really nice old Jensen 12" speakers. The cab sounds fantastic with a Champ but I'm afraid to throw anything more than a Deluxe at it because I'm not sure the Jensen PM12C in there can handle more than 10W or so. I figured the EL84 Tremolox would be a good compromise but 84's can kick out a lot of sound from that small envelope. I really don't want to blow this speaker!

I'll keep an eye on this thread and I look forward to seeing the results. I've built most of the tweed circuits and am just starting to dig into the brown era Fender stuff (just finished a few 6G15's and have a 6G16 started on the bench!).

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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Sun Jan 15, 2012 1:49 pm    Post subject: Reply with quote

Cliff,

Your project idea would be a very unique amp. It wasn't that long ago that I heard about this EL84 Fender amp. I think I would like the EL84's over the 6V6 tubes myself.

Mark
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martin manning



Joined: 06 Jul 2008
Posts: 5326
Location: Queen City

PostPosted: Sun Jan 15, 2012 2:48 pm    Post subject: Reply with quote

Mark and Cliff, since you guys are delving into these brown-era amps, here's an alternative to the tapped treble pot used in the tonestack. This idea popped into my head over the holidays, and a sim shows it to be very close to the original in frequency response. There is just a bit of additional mid scoop, and it doesn't kill the high-end quite as much, but it is very close.
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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Sun Jan 15, 2012 5:25 pm    Post subject: Reply with quote

Martin thanks for the information very appreciated.

I do have the tapped pot so will proceed that way but nice to know one can work around that.

Mark
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Cliff Schecht



Joined: 30 Dec 2009
Posts: 2611
Location: Austin

PostPosted: Sun Jan 15, 2012 6:23 pm    Post subject: Reply with quote

M Fowler wrote:
Martin thanks for the information very appreciated.

I do have the tapped pot so will proceed that way but nice to know one can work around that.

Mark


I don't have a pot and I don't want to buy one. I'll give Martin's circuit a shot for sure. Martin do you mind my asking how you came up with the idea? I guess I can see what you are doing but tapped pots always give me a headache when it comes time to actually design them into a circuit (too many degrees of freedom). Sorta like how those crazy Switchcraft switching style jacks can profoundly confuse with how many solder lugs there are (see below). I did find a 250k pot with a 50k tap (same ratio as 350k/70k) but I don't like changing the tonestack loading unless I adjust all of the R's and C's accordingly.

Thumbnail, click to enlarge.

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martin manning



Joined: 06 Jul 2008
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Location: Queen City

PostPosted: Sun Jan 15, 2012 6:46 pm    Post subject: Reply with quote

Cliff, it was like this: Hmmm... need a 350k pot. OK, put a shunt across a 500k pot. Need a 350k tapped pot... OK, put the tap on the shunt! The real test would be to A-B it with a tapped pot, but I'm betting it will get the job done in good style. A 1M is close enough if you lack a 1.1, the response changes very little. Turned out to be very simple to implement, too.

Last edited by martin manning on Sun Jan 15, 2012 6:48 pm; edited 1 time in total
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Structo



Joined: 17 Oct 2007
Posts: 14246
Location: Oregon

PostPosted: Sun Jan 15, 2012 6:47 pm    Post subject: Reply with quote

Doesn't Weber sell those 350K tapped pots?
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martin manning



Joined: 06 Jul 2008
Posts: 5326
Location: Queen City

PostPosted: Sun Jan 15, 2012 6:50 pm    Post subject: Reply with quote

Structo wrote:
Doesn't Weber sell those 350K tapped pots?

They do, but they are 16mm. This way you can have a matching set of whatever your favorite brand is.
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dayn



Joined: 05 Mar 2007
Posts: 157
Location: seattle, wa

PostPosted: Sun Jan 15, 2012 7:36 pm    Post subject: el-84 tremolux Reply with quote

One on eBay right now:

http://www.ebay.com/itm/STUPID-RARE-Vintage-1961-Pre-CBS-Fender-TREMOLUX-EL84-Guitar-Amplifier-RAAAARE-/360426504615?pt=LH_DefaultDomain_0&hash=item53eb1801a7
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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Sun Jan 15, 2012 9:45 pm    Post subject: Reply with quote

Some good photos with that ebay listing.
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tubeswell



Joined: 27 Mar 2008
Posts: 1644
Location: Wellington. NZ

PostPosted: Mon Jan 16, 2012 2:01 am    Post subject: Re: el-84 tremolux Reply with quote

dayn wrote:
One on eBay right now:

http://www.ebay.com/itm/STUPID-RARE-Vintage-1961-Pre-CBS-Fender-TREMOLUX-EL84-Guitar-Amplifier-RAAAARE-/360426504615?pt=LH_DefaultDomain_0&hash=item53eb1801a7


Yee-ikes. $15k! Shocked I'm sure its worth every penny. Confused

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Last edited by tubeswell on Mon Jan 16, 2012 4:20 pm; edited 2 times in total
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M Fowler



Joined: 16 Jan 2008
Posts: 11122
Location: MN

PostPosted: Mon Jan 16, 2012 3:48 am    Post subject: Reply with quote

Cliff the Fender PA100 I am working on right now has those jacks on the speaker out. Beefy suckers.
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