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[joecool85]

Is this the schematic you used fro the vero layout Joe?

...

There are a few schematics in that thread and I dont know which one you used   I like the idea of having a clean and overdrive channel. But instead of a stompbox I might just put a switch in the amp.

Cheers,

Trent

I used the original schematic from Dean Markley: http://deanmarkley.com/Info/LegacyAmps/Schematics/D1515.pdf

I stopped at the output of the treble pot.  If you build it I would add R11, R12 and C11 between the preamp and poweramp as in the original schematic.

The buffer would be only if you were using it as a stomp box so that if you put it in front of another box it won't cause crazyness.  If you are using it strictly as a preamp in front of a poweramp it is totally unnecessary and I would build it as in my vero.

As for the switch, it is easiest to just use a DPDT switch on the amp as you suggested.  This is how Dean Markley built it as well.

[Hayden]

That link was perfect. Had the photo and lots of other good info. Thank you so much.

[joecool85]

That link was perfect. Had the photo and lots of other good info. Thank you so much.

No problem.  Taylor, the fellow who designed this circuit, is a more frequent poster on diystompboxes than here and that is where he has the build thread.

[Hayden]

With that link I finished the build and am very pleased with the result. Trying different speakers and I'm impressed with the volume and tone. Hooked it up to my EMC bass cab and it drove that 15 inch speaker with no problem. I want to use a smaller speaker and build a nice wooden cabinet with a black plastic faceplater for the control and jack. Thanks again.

[Trent]

Hey all,

I'm still around, just been busy and sick so haven't been in front of computer much.

I'm going to build myself a single speaker cab and found this Jensen speaker that I can get to my door for around $110. http://www.jensentone.com/c10q.php

I don't know much about this sort of thing (as previously stated), so is this a decent speaker for the price? Keep in mind i'm in Australia and we pay more for everything for some reason.

Cheers,

Trent

[joecool85]

Hey all,

I'm still around, just been busy and sick so haven't been in front of computer much.

I'm going to build myself a single speaker cab and found this Jensen speaker that I can get to my door for around $110. http://www.jensentone.com/c10q.php

I don't know much about this sort of thing (as previously stated), so is this a decent speaker for the price? Keep in mind i'm in Australia and we pay more for everything for some reason.

Cheers,

Trent

I've heard great things about those "vintage" Jensens.  I'd say go for it.

[Trent]

Hey, Still here,

I have ordered the speaker and it should arrive today so i'll be building a cab for it in the next week or so.

Can someone give me some advice on cab design for this speaker? I have done a bit of reading and all I have a chieved is a sound feeling of futility. I have a feeling that an open back design would not suit this speaker at all so i'm going to go for a sealed cab. But yeah, any help would be awesome.

And thanks for everything so far, you guys have helped heaps.

Cheers,

Trent

[J M Fahey]

Jensens are very good.
As for a cabinet, I'd search for a classic amp that used a 10" speaker, say a Fender , Laney, etc. and use its size as a guide.
Or you can use a 1x12" combo as a guide.
You can still use a 10" there but the somewhat larger cabinet will give you more body/bass.
You can also buy a Jensen MOD 12 50 for about the same price, and will have a beefier, "better" speaker.
USA prices:
C10Q U$47
MOD 1250 U$49.50

[Trent]

Hi all,

Well i've been pretty busy lately but my amp is moving along nicely. I bought the wood for the cab and i'll put that together this weekend. I have been heaps slow with my circuit however I have a question about the preamp grounding.

As I plan to use the same single 14v supply for the preamp and power amp, I have had a crack at making a dual P/S for the preamp but I'm unsure what grounds become the VGND and what will be V-(or 0V) So a little help there would be much appriciated.

Also As the preamp will be permanently coneected to the power amp is there really any need for the op amp right in front of the TDA7240A? Or does the preamp circuit take care of that?

I have attached an overall drawing I did.

Thanks for your help.

Trent

[Trent]

Hey Hey People! I'm still kicking!

Have been plodding along, breadboarded the power amp and pre amp circuits, and have built the speaker cab. I have designed the pcb and will make it up tomorrow night. All that is left is to find some enclosures for them  both. Anyway here are some pics.

Breadboarding the tiny giant.



Speaker cab









Still a bit to do but i'm happy. I must say i'm rather impressed with my woodworking skills.
Anyway i'll post up pics of the final product.

Cheers

[joecool85]

Looks good so far.  What size speaker are you using?

[Trent]

10 inch. I have to cut a hole in the backing board, it doesn't sound that good as a sealed cab.

[J M Fahey]

Congratulations.
Excellent build. :tu:

[joecool85]

10 inch. I have to cut a hole in the backing board, it doesn't sound that good as a sealed cab.

I've not really heard any sealed cab situations that I like better than open back.  Personal preference I guess.

[phatt]

Having mess with speakers for many years.
That box is miles to big for that sized speaker to work with a sealed back. 8|

Get the dimensions right and sealed back can be rewarding.

Generally open backs sound bigger at first hearing but start gigging at high SPL and sealboxes will deliver better reproduction.
my 2 cents worth.
Phil.