Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on May 22, 2025, 03:18:38 am

Title: BIG SE AMP
Post by: TIMBO on May 22, 2025, 03:18:38 am
Single 25 | KT150 Guitar Amp | 25W Class A — De Cillia Amplification (https://decilliaamplification.com/single-25)
Little amp HUGE sound
Bing Videos (https://www.bing.com/videos/riverview/relatedvideo?pglt=297&q=de+cilla+single+25&cvid=45813e2d5e2e492fa633c18a88f973a3&gs_lcrp=EgRlZGdlKgkIABBFGDsY-QcyCQgAEEUYOxj5BzIGCAEQABhAMgYIAhBFGDkyBggDEAAYQDIGCAQQABhAMgYIBRBFGDwyBggGEEUYPDIGCAcQRRg8MgYICBBFGEHSAQk2NTM2OWowajGoAgCwAgA&PC=LCTS&ru=%2fsearch%3fpglt%3d297%26q%3dde%2bcilla%2bsingle%2b25%26cvid%3d45813e2d5e2e492fa633c18a88f973a3%26gs_lcrp%3dEgRlZGdlKgkIABBFGDsY-QcyCQgAEEUYOxj5BzIGCAEQABhAMgYIAhBFGDkyBggDEAAYQDIGCAQQABhAMgYIBRBFGDwyBggGEEUYPDIGCAcQRRg8MgYICBBFGEHSAQk2NTM2OWowajGoAgCwAgA%26FORM%3dANNTA1%26PC%3dLCTS&mmscn=vwrc&mid=DA7DF1D980542F5DA376DA7DF1D980542F5DA376&FORM=WRVORC&ntb=1&msockid=20f4655f36e411f0a2ecc6bd769c6e03)
@ shooter
I know you have dabbled in these monster SE amps
Would you like to have a crack at what's going on with them and if they have an amp topology
 :icon_biggrin: 
Title: Re: BIG SE AMP
Post by: jbrrrrr on May 22, 2025, 04:26:14 am
From what I gathered from that video, his concept is that it is more realistic to scale down an overbuilt amp that isn't putting out peak dissipation at stock output level - I'm guessing this means that the amp is kind of in "scaled down" mode permanently, even when not using the power scale feature - so instead of trying to make a full throttle output section sound just as good when you cut the power output down, this is just taking an output tube that is always in some degree of power scale output reduction sweep through a spectrum of reduced power - which apparently sounds more consistent - that logic makes sense to me, at least.

There may be more black magic going on, and I may have interpreted that incorrectly - just throwing it out there to see if anyone has any other thoughts.

Title: Re: BIG SE AMP
Post by: tubeswell on May 22, 2025, 06:22:30 am
Changing output tube bias to scale down output power is what Fender did on the Bassbreaker 18-30 (That and changing the B+)
Title: Re: BIG SE AMP
Post by: shooter on May 22, 2025, 06:32:22 am
sounds like a lot "magic words" by a creative writer
by the parts count, looks like they threw in all their favorite pedals to switch in/out for preamp spices.



I got 23W from a KT88
pretty sure Pete put together on the bench a parallel 88, maybe a 120


the $$'s seemed a bit steep but I've been farming for a few years n haven't kept up.


didn't know a 3 position switch n a couple power resistors is proprietary  :icon_biggrin:
Title: Re: BIG SE AMP
Post by: kagliostro on May 22, 2025, 07:40:21 am
At DIY Italia we are testing a prototype of SE around 13W - 14W with a way less expensive tube, a GU-50

Not to say that KT150 or a KT88 aren't to be considered, anything but, say an on budget musician man project

Yes, to use one of those tube, due to the low sensitivity, requires a specific driver circuit but ......

KT150 around 120€

KT88 around 61€

GU-50 around 7.5€ .........

Franco
Title: Re: BIG SE AMP
Post by: scstill on May 22, 2025, 10:51:58 am
Sounds like an Italian rather than a Austrian company :-)

The KT150 has a great looking bulb; design spec says not less than 20w

Thinking you get a similar power output with parallel plate SE (or is that a cheating SE)

What is the real intent of going SE vs PP? Is there a tonal difference between SE and PP (I can't hear it). Or are we just simplifying design by eliminating PI? This decillia missed the simple idea, so many components.

The "Power Knob" might be gimmick as it claims to play at Bedroom levels but lower power doesn't really reduce volume as it implies. I have Egnater Rebel 20 with different power settings, which I am sure reduce the power level, but not much reduction in volume. An MV will actually do this.

You'd think at that price they would provide hand wired rather than PCB.

Title: Re: BIG SE AMP
Post by: shooter on May 22, 2025, 11:19:28 am
Quote
Is there a tonal difference between SE and PP


the biggest difference tonally is the harmonics SE tend to favor odd harmonics where P-P even
the next up is the asymmetry as you hit clipping, (enter into Class A/B)
my favorite, the cleans seem "crisper", one guitarist put it this way;
"You can't be a sloppy player n get away with it on these amps, you hear EVERY missed note, muted string, You have to play your A-game"
Title: Re: BIG SE AMP
Post by: mresistor on May 22, 2025, 12:57:24 pm
Quote
Is there a tonal difference between SE and PP
"You can't be a sloppy player n get away with it on these amps, you hear EVERY missed note, muted string, You have to play your A-game"


That reminds me of when I bought a great big old Peavey bass cabinet  2x15" speakers, and it had a peavey and some other thing in it that I sold off.   Then I found 2 Electrovoice EV15L speakers and they are nearly full range so I bought them and stuck then in that bass cab..  I played a lot of different amps through it and one thing I can say is ... just like the guy above you will hear every little nuance through those speakers.  Now imagine EV15Ls coupled with a high power SE guitar amp. Standelish for sure.
Title: Re: BIG SE AMP
Post by: DummyLoad on May 23, 2025, 04:28:53 pm
Single 25 | KT150 Guitar Amp | 25W Class A — De Cillia Amplification (https://decilliaamplification.com/single-25)
Little amp HUGE sound
Bing Videos (https://www.bing.com/videos/riverview/relatedvideo?pglt=297&q=de+cilla+single+25&cvid=45813e2d5e2e492fa633c18a88f973a3&gs_lcrp=EgRlZGdlKgkIABBFGDsY-QcyCQgAEEUYOxj5BzIGCAEQABhAMgYIAhBFGDkyBggDEAAYQDIGCAQQABhAMgYIBRBFGDwyBggGEEUYPDIGCAcQRRg8MgYICBBFGEHSAQk2NTM2OWowajGoAgCwAgA&PC=LCTS&ru=%2fsearch%3fpglt%3d297%26q%3dde%2bcilla%2bsingle%2b25%26cvid%3d45813e2d5e2e492fa633c18a88f973a3%26gs_lcrp%3dEgRlZGdlKgkIABBFGDsY-QcyCQgAEEUYOxj5BzIGCAEQABhAMgYIAhBFGDkyBggDEAAYQDIGCAQQABhAMgYIBRBFGDwyBggGEEUYPDIGCAcQRRg8MgYICBBFGEHSAQk2NTM2OWowajGoAgCwAgA%26FORM%3dANNTA1%26PC%3dLCTS&mmscn=vwrc&mid=DA7DF1D980542F5DA376DA7DF1D980542F5DA376&FORM=WRVORC&ntb=1&msockid=20f4655f36e411f0a2ecc6bd769c6e03)
@ shooter
I know you have dabbled in these monster SE amps
Would you like to have a crack at what's going on with them and if they have an amp topology
 :icon_biggrin:

Ahem! :p

https://el34world.com/Forum/index.php?action=dlattach;topic=25469.0;attach=80910

40W of parallel SE goodness with a pair of KT120 and 750V to the anodes.  :icon_biggrin: 

--Pete
Title: Re: BIG SE AMP
Post by: shooter on May 23, 2025, 05:43:03 pm
 :laugh:
how's the hernia healing  :icon_biggrin:




another "feature" of a good SE, they take pedals real well....as long as you don't slam the PA with a signal that squares out, otherwise it'll make an evil sound!!!  :icon_biggrin:


this takes the SE from a basic class A to multi-talented sounds, easily configured or re-configured with cable, no fancy preamp thought or soldering required.
Title: Re: BIG SE AMP
Post by: DummyLoad on May 23, 2025, 10:34:35 pm
:laugh:
how's the hernia healing  :icon_biggrin:



What hump? What hernia?  :icon_biggrin:   

--Pete
Title: Re: BIG SE AMP
Post by: kagliostro on June 01, 2025, 11:07:16 am
On the cheap version

https://community.dfrobot.com/makelog-313337.html (https://community.dfrobot.com/makelog-313337.html)

Just kidding  :icon_biggrin: :icon_biggrin:

Franco

Title: Re: BIG SE AMP
Post by: mresistor on June 01, 2025, 12:26:24 pm
Hey Kag   I've got a 6C21 here maybe Timbo could use it in his big SE amp..   it's BIG!  Filaments will blind ya.



Title: Re: BIG SE AMP
Post by: shooter on June 01, 2025, 02:14:23 pm
I see that n raise a 5KW Class A, (class C 25KW)  :icon_biggrin:
Title: Re: BIG SE AMP
Post by: kagliostro on June 01, 2025, 05:00:39 pm
Old stuff 😉

https://el34world.com/Forum/index.php?topic=10262.0 (https://el34world.com/Forum/index.php?topic=10262.0)

Franco

Title: Re: BIG SE AMP
Post by: glass54 on June 01, 2025, 09:43:38 pm
Sorry Shooter, I'm out can only do about 1kW class A  :BangHead:
Aussies AWA Radiotron JAN833A
Regards
Mirek
Title: Re: BIG SE AMP
Post by: Carlsoti on June 03, 2025, 11:14:37 pm
...
40W of parallel SE goodness with a pair of KT120 and 750V to the anodes.  :icon_biggrin: 

--Pete

Was there a discussion thread on this amp? I'm interested in learning more.  Sound clips, etc?
Title: Re: BIG SE AMP
Post by: pullshocks on June 14, 2025, 09:33:40 am
I happened to see this SE guitar amp by JJ that uses the 300B…
https://www.jj-electronic.com/en/jj-one (https://www.jj-electronic.com/en/jj-one)
Title: Re: BIG SE AMP
Post by: scstill on July 18, 2025, 02:58:33 pm
A recent video build of a kt88 SE
i=tbm84lkVxgxOZPbc
Title: Re: BIG SE AMP
Post by: uki on July 19, 2025, 02:10:31 am
Check out this tread: https://el34world.com/Forum/index.php?topic=20353.msg214213#msg214213