Now hands up who want to try a 40W SECA version?

[Sovereign]

It's not quite a finished project yet. I am about to build another one exactly the same and place it on top so the fins of the two amps line up perfectly, that was the idea of leaving the heatsinks exposed.
So soon I should have a Wonfor Tower of Power

 

[amirm]

How adequate is 40 watts?

 

[Sovereign]

I have used this amp on several sets of speakers with some of them being quite inefficient. I have always found this amp to have oodles of power and never broken a sweat really.
Maybe Colin can comment on the difference between class A watts and a/b watts

 

[RayDunzl]

How adequate is 40 watts?

Let's see:

40 watts at 8Ω = 17.8Vrms = 25.28Vpk

My speakers (4Ω) gave 87dB at the listening position with 2.83Vrms...

Assuming the SECA can hold its volts and "double down" flowing 80W across 4Ω, some guesstimating:

2.83Vrms- 2W - 87dB
4.00Vrms - 4W - 90dB
5.65Vrms - 8W - 93dB
8.00Vrms - 16W - 96dB
11.3Vrms - 32W - 99dB
16.0Vrms - 64W - 103dB
17.8Vrms - 80W - 104dB

That's right at my usual loud peak level, so, might be just adequate for me...

---

Playing a bit extra loudly recently I saw 50V on the Fluke, assuming that's a peak reading:

50Vpk x .7071 = 35.35Vrms

35.35Vrms / 16.0Vrms = 2.209 voltage ratio
2.209 voltage ratio = 6.88dB gain
103dB + 6.88dB = 109.88dB

35.3Vrms - 312.4W - 109.88dB (I think I saw 110)

So, not quite adequate for headbanging and amp cooking (146F on the heatsink at that time) here. Not that I do that, 120F is more normal hot and loud on the sinks, with about 100F on the case cover.

---

What's the rail voltage on the SECA 40W?

 

[Sovereign]

All reads double Dutch to me mate. We need the big man himself to comment

 

[Thomas savage]

We need ' The wonf'

 

[fas42]

How adequate is 40 watts?

It's all about the "competence" of those watts - my first serious amp, an x hundred watt Perreaux battleship, started faltering at far too low levels - I learnt a lot sorting that out. 20 or so of fully usable watts is fine - can give one big, big pipe organ sound on average sensitivity speakers, no prob's ...

 

[Sal1950]

Playing a bit extra loudly recently I saw 50V on the Fluke, assuming that's a peak reading:

OH, you got a Fluke!
My old Simpson 461-2R is in the RadioMuseum. LOL
Still works well for my uses.
http://www.radiomuseum.org/r/simpson_digital_multimeter_461.html?language_id=2

 

[Colin James Wonfor]

James is +30V & -30V less 3V thus 27V rails.
About 44W @ 8 Ohms

 

[RayDunzl]

My listening right now at 3:30am, 97.4dB peak SPL, 12.44Vpk on the meter.

12.44Vpk = 8.8Vrms = 9.68W @ 8 Ohm

40 watts would be just fine tonight.

 

[Colin James Wonfor]

Sorry I had a minor Heart Attack last week and Have just been released so I will be having a small rest before I get married on Saturday.

 

[Thomas savage]

Sorry I had a minor Heart Attack last week and Have just been released so I will be having a small rest before I get married on Saturday.

Glad your ok, the wonf endures.. There's no keeping him down!

 

[amirm]

Sorry I had a minor Heart Attack last week and Have just been released so I will be having a small rest before I get married on Saturday.

Whoa! You say both so casually Colin! So happy to see you recover and much congratulations on marriage.

 

[Sal1950]

Sorry I had a minor Heart Attack last week and Have just been released so I will be having a small rest before I get married on Saturday.

Whoa! You say both so casually Colin! So happy to see you recover and much congratulations on marriage.

Dang, +1K on that.
Get better Colin and congrats on the upcoming marriage.

 

[Colin James Wonfor]

FUN FUN FUN and God loves duck to they make him giggle and with my stick I waddle also he he. Nerves now take over from pain he he.
The H.A. was due to silly practitioner telling me to stop warfarin whilst I was on Anti Bods, but the Mech Valve (not tube) jammed and bang H.A. so be warned it bloody hurts a lot.
So the next two days up the hospital for checks and the tame Vampire, (red-headed nurse jummy) .
Back in mid Novs so you lots take care best Wonf.

 

[Colin James Wonfor]

Back alive and happy,

The Mobile Phone exploded in the hotel a Moto E and set the fire alrm off, and the engine on the mini cruse ship ship died and the waves were fantastic I fell asleep, he he On the way to Porto Santo Island from Madeira.
Lovely warm days, but it was cold back here in the UK brrrrr

Are you all well?

 

[Sovereign]

Nice to have you back Colin!!!
Here is some more info on my amp

Freq Response 5.0Hz = 200KHz Flat
Freq Response 1.0Hz = 250KHz -3dB
Phase change 20Hz - 20KHz 2deg
Damping Factor 2000+
Output 40W RMS Min 8R
Output 61W RMS Min 4R
Input 1.2V full output
Distortion THD before clipping less than 0.01%
Distortion THD on the verge of clipping less than 1%
Input Impedance 10K @ 100pF
Power consumption Static 200W/Channel
Power consumption full output 310W/Channel

 

[Sal1950]

The Mobile Phone exploded in the hotel a Moto E and set the fire alrm off, and the engine on the mini cruse ship ship died and the waves were fantastic

Your just not having a real good run are you?
Sorry to hear that but I'm sure there are a lot of good parts going on your not detailing.
Enjoy the honeymoon and stay well!
Sal

 

[Colin James Wonfor]

Valley of the Nuns in Madeira our honeymoon.

Maria and I. Together at last after 25yrs as friends, great.

 

[Sal1950]

Maria and I. Together at last after 25yrs as friends, great.

That's really awesome, so glad for you!
Congratulations again.
Sal