ping wg_ski.............Do you have a link to the Hohner amps you spoke of?
If we would like a reg of less than 200V it starts to make sense to make a negative reference for the error amp.
When we put a reference under the cathode the tube soon runs out of plate volts to pull the passer tube down far enough.
The error amp cathode then to common. If you are not looking for a one tube solution a 6AU6 error amp would be OK.
If say SE 2E26s or 2E26s in Class A, then not much more than 160V is required for G2s in typical operation.
Not long ago someone here on DIY was either building or had built an amp with 2E24s.
Some adventurous builders like to smoke members of the 6W6 / 25L6 family in their sockets
running 300V plate & 150V on G2. A good place for a simple regulator on G2!👍
As usual, do yourself a favor & check the relevant data sheet. Here they are to make it easy,
This time pay some attention to what it tells us. 😀
https://www.diyaudio.com/community/threads/those-magnificent-television-tubes.211254/page-86
was the last place those Hohner amps were recently discussed. It was certainly getting the wheels turning about jazzing up 6CW5’s. Apparently, they will take the abuse better than 6W6’s. I think Tubelab George was the one doing that - and discovered that the 150V screen rating is a hard limit.
was the last place those Hohner amps were recently discussed. It was certainly getting the wheels turning about jazzing up 6CW5’s. Apparently, they will take the abuse better than 6W6’s. I think Tubelab George was the one doing that - and discovered that the 150V screen rating is a hard limit.
THX for that link WG. I found the cct here-
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The PS is a full wave doubler, the screens run at half B+ at the CT of the cct.
Unfortunately the schematic doesn't tell us what the HV driving the doubler is.
Should be possible to backup from power out thru the OPT tho.
I wonder if the 45W is real or peak. In those daze amp builders were notorious for
quoting the largest number possible but didn't tell us how they got the number claimed.
All marketing.
The GE data sheet shows one set of conditions that doesn't blow the lid off that is good for 25W.
With a bit of a push as is often done on instrument amplifiers perhaps 40W is possible. Rock Band amps do that all the time.
Just keep a box of spare toobz handy. 😱
On the Tungsol sheet, bottom of p2 reference is made to a 2-tone test, something I've never seen listed for an audio tube before.
Farther down on p5 we are told in the remarks the tones are of equal amplitude, a test I've used for many years.
This is one way of looking at Intermodulation Distortion (IMD).
Another surprise to many, more tones means less audio power available before clipping, the peaks of the signals add.
When we do the math, equal tones looks like half power.
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What do you think about this tube schematic?
Amazing! 40 watts from a pair of 12-watt valves - without melting them - sounds like the sort of thing only Tubelab George regularly manages to pull off! Do you by any chance have a link to a schematic for that Hohner Orgaphon 50? That sounds like something worth studying, to try and figure out...- Gnobuddy
- Post #41
- 2017-07-13 5:23 am
- Forum: Instruments and Amps
The PS is a full wave doubler, the screens run at half B+ at the CT of the cct.
Unfortunately the schematic doesn't tell us what the HV driving the doubler is.
Should be possible to backup from power out thru the OPT tho.
I wonder if the 45W is real or peak. In those daze amp builders were notorious for
quoting the largest number possible but didn't tell us how they got the number claimed.
All marketing.
The GE data sheet shows one set of conditions that doesn't blow the lid off that is good for 25W.
With a bit of a push as is often done on instrument amplifiers perhaps 40W is possible. Rock Band amps do that all the time.
Just keep a box of spare toobz handy. 😱
On the Tungsol sheet, bottom of p2 reference is made to a 2-tone test, something I've never seen listed for an audio tube before.
Farther down on p5 we are told in the remarks the tones are of equal amplitude, a test I've used for many years.
This is one way of looking at Intermodulation Distortion (IMD).
Another surprise to many, more tones means less audio power available before clipping, the peaks of the signals add.
When we do the math, equal tones looks like half power.
Attachments
The other schematic from the TV tubes thread showed 380V on the plate and 220 on the screen. Tubelab style. That would do the 45 watts if it didn’t sag too much under load. It would take 330V, 4K a-a and negligible copper losses to do. The tubes could push just enough current to do it with the screen at 200 (When they’re new of course).
It is kind of funny that the Tungsol data sheet specifies SRPP operation and IMD. GE’s “25 watts” is optimistic at best for 250V (I think I calculated a little under 24). Distortion figures seem surprisingly low for tubes pushing a lot of current - it’s more typical of 8k or 10k loading than 3k.
It is kind of funny that the Tungsol data sheet specifies SRPP operation and IMD. GE’s “25 watts” is optimistic at best for 250V (I think I calculated a little under 24). Distortion figures seem surprisingly low for tubes pushing a lot of current - it’s more typical of 8k or 10k loading than 3k.