Hammond 1650W

[Koifarm]

Here in the netherlands they have build this year a 300Watt amp with 6550 tubes. If you interrested i can scan the artilkel with schematics.

[Brett]

Originally posted by G.Kleinschmidt

Attached below are a few crappy conceptual drawings of how I’m going to construct this amp. (No dimensions added yet and the scribbles are not really to scale, but they should give an idea.)
The amp will stand upright, like a tower, probably 1 to 1.5m tall. It will be constructed around a TIG welded frame made from 50mm by 50mm aluminium angle 5mm thick. This frame will support everything, including the transformers.

Hilarious. Finally something that may outdo the hugeness of my class A PP triode 813 design that was the size of a 3 drawer filing cabinet/channel and weighed 90kg ea. The sort of OTT PSU and LCLC filament supplies were the main reason for the weight.

I'm gonna watch this project with interest.

[tubelab.com]

There is a higher power and higher bandwidth alternative. Though shipped to AU Im sure its a pretty penny.
400W toroidal OPT. Supports 8 KT88.

They had some non potted versions of these on their surplus page, but they are now gone. I got a pair and these are the ones that I am using. The transformers were $138 USD each plus $65 shipping, DEAL!

[richwalters]

GKlein# spare a thought.
One of the biggest hiccups with the big game amps with crowded top chassis is ventilation. If one keeps to the 4" valve-holder centre to centre convention (as per KT88 GEC recommend) then for long term reliability a holed top chassis will keep it around 25°C above ambient without a fan. That is already stewing. This issue has been in another thread.
I learn't early on to keep electrolytics in coolest places low down and tubes in upper places. Obviously if you throw-in a fan then there is added noise.
6 x KT88 creates enough heat to simmer an egg and if you are having regulator tubes thrown in, you can cut down the room thermostat.

richj

[GK]

Originally posted by richwalters
GKlein# spare a thought.
One of the biggest hiccups with the big game amps with crowded top chassis is ventilation. If one keeps to the 4" valve-holder centre to centre convention (as per KT88 GEC recommend) then for long term reliability a holed top chassis will keep it around 25°C above ambient without a fan. That is already stewing. This issue has been in another thread.
I learn't early on to keep electrolytics in coolest places low down and tubes in upper places. Obviously if you throw-in a fan then there is added noise.
6 x KT88 creates enough heat to simmer an egg and if you are having regulator tubes thrown in, you can cut down the room thermostat.

richj

Oh c’mon, it's only going to dissipate about 700W at idle
My drawing wasn't very good, but standing 1 to 1.5 metres tall, I'll have plenty of room to spread the valves out.
Nearly all the dissipation is in the tubes and these stick out horizontally into the open through the vertical front panel.
I don't think there will be much of a problem with heat build-up on the inside.
I guess that I could easilly put some insulative mat between the inside of the front panel and the sub chassis onto which the valve sockets mount, as a good measure to really keep the heat on the outside.
This thing isn't going to be my main amp. It's going to be more of a piece of furniture in the corner of my living room, standing besides a hybrid (but mostly solid-state) 200W per channel class A amp and a 1kW per channel completely solid state class A amp that uses tracking rails to keep the dissipation manageable - both are currently under construction.

These amps will be lucky to get used more than an hour a month, and definitely not at all on warm days!

[GK]

Originally posted by Koifarm
Here in the netherlands they have build this year a 300Watt amp with 6550 tubes. If you interrested i can scan the artilkel with schematics.

Yes, thanks! If the file size / resolution constraints here are not too tight, just attach them in this thread.

[tubewade]

Humongous amps like these can be a supplement to your furnace when used during the cold months of the year. That's when I get to play with my big amplifiers. During the hot months I use small SE amplifiers most of the time.

Many of you probably know this, but for the benefit of those who don't, an amplifier dissipating 700 watts of heat will add about 2310 btu of heat to the room. Two will add 4620 btu and that is enough to heat a small room significantly. An amplifier dissipating 150 watts will only add about 495 btu. On average, a resting adult generates about 400 btu of heat, a 100 watt incandescent lamp; 330 btu.

Just some points of reference.

[GK]

Originally posted by tubewade
Humongous amps like these can be a supplement to your furnace when used during the cold months of the year. That's when I get to play with my big amplifiers. During the hot months I use small SE amplifiers most of the time.

Many of you probably know this, but for the benefit of those who don't, an amplifier dissipating 700 watts of heat will add about 2310 btu of heat to the room. Two will add 4620 btu and that is enough to heat a small room significantly. An amplifier dissipating 150 watts will only add about 495 btu. On average, a resting adult generates about 400 btu of heat, a 100 watt incandescent lamp; 330 btu.

Just some points of reference.

700W is what my radiator puts out on the low setting - just right for a cool evening.

[tubelab.com]

Humongous amps like these can be a supplement to your furnace when used during the cold months of the year.

We don't have any cold months, just warm and hot (85 F today). When I was actually considering building a 100 WPC SE amp using 833A's I was planning a scheme to vent the heat outside the house using a clothes dryer vent. Reality, and the lack of affordable OPT's, set in and killed that project.

Before I decide on the final implementation of my monster amp I will have developed a high efficiency tube amp design. I want the total dissipation under 200 watts. Tracking rails and SMPS technology is a given.

[Toobstheway]

While we are on the topic of "Big" amps, checkout this one by Bob Danielak. It's a 10 year old design, but imagine what some new technology could do for it? http://www.geocities.com/TimesSquare/1965/pp3cx300.html