mini D-HRM amp

[Geezer]

Sorry to say, this project is dead (or at least has taken a major detour).
 
The preamp sounded really good when run into a PP poweramp, but just couldn't generate enough grunt for the big octals SE.

By "really good", I mean:
*with the OD switched in, it had good tone, & I suspect I could have tweaked it to perfection given enough time, but...
*I guess there's a reason you never hear clips of the "Clean" section of the Dumble amps....it was quite un-inspiring.

I am in the process of re-working the circuit into a HoSo preamp, with the Dumble OD section intact. I'm going to run a 2x6V6 PP poweramp (since the octal sockets are already there), but have to add several more 9-pins for the CF & PI.

Lots of extra work, but I'm confident I can turn this project into something useful in the end.

Thanks again for all the help & advice.

Geezer

[Shrapnel]

IF it can drive a 6BQ5 or EL84 fine, a big bottle that *might* work would be a 7591. It has a similar gain level. (I won't go as far as to say the charts are the same, I know better that they don't match that much.) and is similar to a 6L6 in some other aspects. I've heard it sounds somewhere between a EL34 and 6L6. (I'll know more when I finally get my project, now over a year old, finished. Largest aspect is a cab for the head, the rest is me finishing up the wiring. It is no mini D-HRM or HoSo though.)

[tubenit]

I am in the process of re-working the circuit into a HoSo preamp, with the Dumble OD section intact. I'm going to run a 2x6V6 PP poweramp

Maybe something like this?  However, this has more of a D_mble LTPI vs. HoSo56 LTPI.

With respect, Tubenit

[Geezer]

Yep, that's pretty much what I've drawn up.

I drilled & installed the extra sockets last night, now have to re-load the board & re-wire pretty much everything

 :crybaby2:

I should have it up & running this weekend.

The only thing I'm wondering about is the Clean Master.....whether to switch it out (as drawn) when the OD is engaged, OR to leave it in the circuit. I can easily try it both ways by simply moving 1 wire, so I'll try it on-the-fly & see what work/sounds best........

[tubenit]

Looking forward to your new innovative amp & tone review!  Thanks for blazing a trail that all the rest of us benefit from. It's appreciated.

Best regards, Tubenit

[topbrent]

Sorry if this is rehashing old info regarding the Dumble style preamp into a SE output.

Loosechange had a nice series of SE 6L6 or EL34 SE builds. D'Lite ODS pre, Marshall Jubilee, Blackface champ, ect.

Maybe it's too late for the builds at hand,  but these are nice clean builds with a pertinent theme.

D'lite Pre
http://www.el34world.com/Forum/index.php?topic=9003.0

Marshall Jubilee pre
http://www.el34world.com/Forum/index.php?topic=8494.0
Champ Pre
http://www.el34world.com/Forum/index.php?topic=7862.0

[tubenit]

Loosechange had a nice series of SE 6L6 or EL34 SE builds. D'Lite ODS pre

from page 2 of this thread is LooseChange's quote here:

From my experience building one... the preamp (especially the clean) does not have enough drive. It's funny how you jumped it over to a PP EL84 power amp. I did the exact thing when I first powered the amp up and noticed the low output. AND it did sound great.

It left me wondering whether is D'Lite SE was successful or not successful?  Particularly since he later recommended switching to a p/p with LTPI further down on page 2.   I am not clear what his results were?

With respect, Tubenit

[Rev D]

 Was there more gain to be had in the clip that started this thread? While it was a nice clean tone, it didn't sound like it had a lot of extra balls so to speak? Were there any clips that had more gain than that?

Regards,

Don

[tubenit]

Were there any clips that had more gain than that?

Yes

[jojokeo]

I finished my Bumblewatt and my clean AND dirty channels have too much power. I can only barely crack open the master to about "2". I'm still working on dialing things in at this point. Also, I didn't exactly follow Matt or Geezer's schem but it's generally close to the same preamp flow chart idea w/ an 18 watt style pa.