New SE With Triode Mode KT120/150
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#121 Re: New SE With Triode Mode KT120/150
Spent time today dismantling the Super Rocky. Where once I had a working amp, I now have a pile of chokes and transformers.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#122 Re: New SE With Triode Mode KT120/150
Awww... poor Super Rocky !
"Once you find out ... the Circumstances ; then you can go out"
- pre65
- Amstrad Tower of Power
- Posts: 21373
- Joined: Wed Aug 22, 2007 11:13 pm
- Location: North Essex/Suffolk border.
#123 Re: New SE With Triode Mode KT120/150
Yeah, I had that when I dismantled two 50W mosfet amps. Even though MoFo is on the home straight there are still a lot of bits left over.Cressy Snr wrote: ↑Thu Jul 09, 2020 9:01 pm Spent time today dismantling the Super Rocky. Where once I had a working amp, I now have a pile of chokes and transformers.
Looking forward to seeing the finished article Steve.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- Paul Barker
- Social Sevices have been notified
- Posts: 8863
- Joined: Mon May 21, 2007 9:42 pm
#124 Re: New SE With Triode Mode KT120/150
Well Barbaric nearly morphed into a Matrix. But it’s not home and dry. If the GK71 Matrix is as hoped, I’ll have to adapt Barbaric. To which end I’ll rig up a socket in each amp to land the Lundahl output transformers on the amp I’m playing.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#125 Re: New SE With Triode Mode KT120/150
Today, I am mostly: scraping meticulously, the paint from the large mains transformer end-bells. Got one done. It’s an hour’s work to do each one. Could have gone out and bought chemical stripper of course, but I’m from Yorkshire.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- pre65
- Amstrad Tower of Power
- Posts: 21373
- Joined: Wed Aug 22, 2007 11:13 pm
- Location: North Essex/Suffolk border.
#126 Re: New SE With Triode Mode KT120/150
There's a joke there Steve, but I'm far too polite.Cressy Snr wrote: ↑Fri Jul 10, 2020 11:11 am Today, I am mostly: scraping meticulously, the paint from the large mains transformer end-bells. Got one done. It’s an hour’s work to do each one. Could have gone out and bought chemical stripper of course, but I’m from Yorkshire.
The devil is in the detail, which is why your builds are so good.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#127 Re: New SE With Triode Mode KT120/150
Yes you have to be very careful how you describe transformer covers,
Sgt. Baker started talkin’ with a Bullhorn in his hand.
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#128 Re: New SE With Triode Mode KT120/150
Iron is all mounted, both inside and out. So it’s definitely time for the traditional photo, giving an idea of of what it will look like when it’s finished:
I’m pleased with the aesthetics. And it doesn’t sag.
I’m pleased with the aesthetics. And it doesn’t sag.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#129 Re: New SE With Triode Mode KT120/150
Looks great steve..
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#130 Re: New SE With Triode Mode KT120/150
Yesterday and today’s progress:
Heater wiring, busbars and power supplies next, but I have a washing machine to fit tomorrow, so how much will get done on the amp I don’t know.
Mains is all done, all tag strips terminated and the DC heater module has been pre set for 4V.Heater wiring, busbars and power supplies next, but I have a washing machine to fit tomorrow, so how much will get done on the amp I don’t know.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#131 Re: New SE With Triode Mode KT120/150
Gravity always wins - look in the mirror!
Anyway, good progress Steve and a neat job.
Have you given up on the 13E1?
Sorry, I couldn't resist!
-
- Amstrad Tower of Power
- Posts: 10552
- Joined: Wed May 30, 2007 12:25 am
- Location: South Yorks.
#132 Re: New SE With Triode Mode KT120/150
Yes, I’m afraid the 13E1 SEOTL is history.
The thing sounds wonderful, but really needs 16 Ohm speakers to be of much practical use. Nick measured it at 600mW into an 8 Ohm load before the distortion shot up; that’s less power than one of those ‘Darling’ amps. Should have thought on while we were at it, to have measured it at 16 Ohms. I suspect the power would have easily tripled.
Wolfgang and yourself have much more suitable speakers than I have, both in terms of efficiency and impedance, so the SEOTL concept has a far better chance, with your systems.
I started the build to try to prove to myself that I could design and build an OTL and not have it catch fire or explode. I succeeded with that and I’ve had a real taste of what an OTL is capable of. I wouldn’t have missed that experience for the world. OTLs are a unique sound.
The thing sounds wonderful, but really needs 16 Ohm speakers to be of much practical use. Nick measured it at 600mW into an 8 Ohm load before the distortion shot up; that’s less power than one of those ‘Darling’ amps. Should have thought on while we were at it, to have measured it at 16 Ohms. I suspect the power would have easily tripled.
Wolfgang and yourself have much more suitable speakers than I have, both in terms of efficiency and impedance, so the SEOTL concept has a far better chance, with your systems.
I started the build to try to prove to myself that I could design and build an OTL and not have it catch fire or explode. I succeeded with that and I’ve had a real taste of what an OTL is capable of. I wouldn’t have missed that experience for the world. OTLs are a unique sound.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#133 Re: New SE With Triode Mode KT120/150
Did you try to reduce the NFB? There is a sweet spot with max. power and ideal NFB with these OTLs. You don't need to adjust for lowest DF but for ideal DF that works best with your speaker /amp combo. Sounds also so much better.Nick measured it at 600mW into an 8 Ohm load before the distortion shot up
#134 Re: New SE With Triode Mode KT120/150
Sorry to continue the off-topic diversion Steve...
I understand where you're coming from with the 13E1. The 13E1 with my 150hm Lowther horns continues to delight me and gives me a better balanced sound than the 300B SE-OTLs, not quite as sweet at the top but a much more full-bodied sound, however, I'm conscious that I have very little power to play with and, as I've mentioned before, that has given me something of a quandry regarding the Lii Audio speakers - to use the Lii units I think some more power will be required. With the results I now have I'm seriously thinking of sticking with the Lowthers, or do I build a MoFo or Mellow OTL to drive the Lii units? I've almost finished the 6C33C SE-OTL too, just to add more variables into the mix.
It might be interesting for you to try a MoFo (or, less likely, something like a Mellow or Transcendent Pinnacle) with your speakers to give a flavour of what more OTL Watts might do with them?
Anway, back to your project at hand...
I understand where you're coming from with the 13E1. The 13E1 with my 150hm Lowther horns continues to delight me and gives me a better balanced sound than the 300B SE-OTLs, not quite as sweet at the top but a much more full-bodied sound, however, I'm conscious that I have very little power to play with and, as I've mentioned before, that has given me something of a quandry regarding the Lii Audio speakers - to use the Lii units I think some more power will be required. With the results I now have I'm seriously thinking of sticking with the Lowthers, or do I build a MoFo or Mellow OTL to drive the Lii units? I've almost finished the 6C33C SE-OTL too, just to add more variables into the mix.
It might be interesting for you to try a MoFo (or, less likely, something like a Mellow or Transcendent Pinnacle) with your speakers to give a flavour of what more OTL Watts might do with them?
Anway, back to your project at hand...
Sorry, I couldn't resist!
#135 Re: New SE With Triode Mode KT120/150
I've a single nos philips 9710a driver (800 ohm) been looking for a second for years, if I was building an otl i would be based on that driver, most of the philips full range drivers have a good sound.
I did wonder about winding speaker coils.. I have all the stuff I need to do it, but I've so many other things on.
Good progress Steve... I'm sure
I did wonder about winding speaker coils.. I have all the stuff I need to do it, but I've so many other things on.
Good progress Steve... I'm sure
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number