Search found 487 matches
- Mon Apr 17, 2023 9:10 pm
- Forum: Technical Discussion
- Topic: THD hot plate serious question. DID IT KILL MY AMPS?
- Replies: 7
- Views: 1930
Re: THD hot plate serious question. DID IT KILL MY AMPS?
By putting an attenuator on a setting that expects a load, and not hooking up a load, you're presenting a higher impedance to the amp, which puts a bit of strain on the output transformer and output tubes. As you've observed, doing this isn't an instant death sentence, but it's not good for the amp....
- Wed Apr 05, 2023 6:46 pm
- Forum: Technical Discussion
- Topic: HEX Electrics 300X
- Replies: 12
- Views: 1780
Re: HEX Electrics 300X
Cool amp, looks as heavy as my old PS300.
The UL connection keeps the screen voltage lower than the plate voltage, which is much kinder to the screens than the typical fixed screen supply.
The UL connection keeps the screen voltage lower than the plate voltage, which is much kinder to the screens than the typical fixed screen supply.
- Wed Mar 15, 2023 5:45 pm
- Forum: Technical Discussion
- Topic: 2023 Monkeymatic Black Butte Desktop #4
- Replies: 11
- Views: 948
Re: 2023 Monkeymatic Black Butte Desktop #4
I have something similar that'd I've used in my shop forever. The main differences between the two are that I don't have the noval socket or adjustable cathode resistor, and I'm using a tapped Hammond OT, so I have three output jacks "Lo Z, Med Z, Hi Z" :) I also have bypass switches for the second ...
- Tue Mar 07, 2023 6:13 pm
- Forum: Vox/Hiwatt Discussion
- Topic: Tube shield in a Hiwatt?
- Replies: 16
- Views: 4918
Re: Tube shield in a Hiwatt?
Very late to the thread, but I really think the shield was originally to keep the output tube heat away from the can caps, which were in close proximity and were not hi-temperature spec electrolytics. It also helped guide the hot air around the output tubes up and through the top vent in the cabine...
- Tue Mar 07, 2023 6:05 pm
- Forum: Vox/Hiwatt Discussion
- Topic: Hiwatt / Laney ∆
- Replies: 1
- Views: 2062
Re: Hiwatt / Laney ∆
The brand of transformers is the only link between the two. Partridge, like all transformer manufacturers, routinely made custom transformers to spec for amp manufacturers.
Cool amp, btw.
Cool amp, btw.
- Tue Mar 07, 2023 6:03 pm
- Forum: Vox/Hiwatt Discussion
- Topic: Hiwatt Hybrid Preamp
- Replies: 16
- Views: 9296
Re: Hiwatt Hybrid Preamp
Sorry, I missed this thread Q - any good quality transformers with appropriate specs should work fine. The circuit and the stiff power supply are the elements most responsible for the Hiwatt sound, imo.
- Tue Mar 07, 2023 5:57 pm
- Forum: Technical Discussion
- Topic: New JJ 6v6S very odd issue
- Replies: 42
- Views: 2628
Re: New JJ 6v6S very odd issue
I've read that JJ 6V6 tubes are closer to 6L6 in internal construction. This would explain why they bias a bit different than NOS 6V6. This is also likely why they seem to handle higher plate voltages than true 6V6 tubes.
I like the TADs for current manufacturer.
I like the TADs for current manufacturer.
- Tue Mar 07, 2023 5:36 pm
- Forum: Technical Discussion
- Topic: Really need some help!!!!
- Replies: 7
- Views: 871
- Fri Mar 03, 2023 8:58 pm
- Forum: Technical Discussion
- Topic: Resistors for the rest of us
- Replies: 29
- Views: 4008
Re: Resistors for the rest of us
https://www.mouser.com/c/?q=xicon%201w%20resistor
You can buy one for $0.20 (and pay $12 for shipping, sigh).
You can buy one for $0.20 (and pay $12 for shipping, sigh).
- Thu Mar 02, 2023 9:15 pm
- Forum: Technical Discussion
- Topic: Resistors for the rest of us
- Replies: 29
- Views: 4008
Re: Resistors for the rest of us
Note the KOA/Speer ones are ~47mm (< 2") long, per the datasheet. The Xicon (Tyco) 1W carbon films are inexpensive and work well, are only a bit larger than the old 1/2 watts, and are longer that the new 1/2 watts (~60mm). They are also available in a wide range of values. This latter is becoming mo...
- Thu Mar 02, 2023 9:01 pm
- Forum: Technical Discussion
- Topic: Need help to convert from a Bulgin plug to a IEC compliant fused socket.
- Replies: 7
- Views: 669
Re: Need help to convert from a Bulgin plug to a IEC compliant fused socket.
In the UK, the live wire is brown, the neutral wire is blue, and the ground wire is green/yellow.
The live wire on a US socket is the longer blade, or top left when looking at the socket with the ground hole on the bottom. The other blade is neutral.
The live wire on a US socket is the longer blade, or top left when looking at the socket with the ground hole on the bottom. The other blade is neutral.
- Mon Feb 27, 2023 6:38 pm
- Forum: Technical Discussion
- Topic: 6V6 versus 6L6 schematics
- Replies: 16
- Views: 1781
Re: 6V6 versus 6L6 schematics
Andy has a good point. A lot more stressed output tubes fail via screen grid vs. any other mode. It just cost money to reduce the screen voltage significantly (particularly before the advent of HV FETs) - this is the main reason why traditional designs don't do this.
- Fri Feb 24, 2023 9:35 pm
- Forum: Technical Discussion
- Topic: 6V6 tonal character.
- Replies: 22
- Views: 2008
Re: 6V6 tonal character.
I'm not quite sure what you're asking. :) To my ears, 6V6s sound like mini-6L6s. I quite like them, and use them in all my more recent 20-ish watt builds (and once even in a 4x 30-ish watt design). They are typically run at voltages in excess of what the old data sheets recommend. They are similar i...
- Fri Feb 10, 2023 8:55 pm
- Forum: Technical Discussion
- Topic: How does the Mesa Boogie SOB P.I. stage work?
- Replies: 20
- Views: 1904
Re: How does the Mesa Boogie SOB work?
A constant current source (CCS) does it's best to keep the current flowing through itself constant (as the name implies :)). This means it appears as a very high impedance looking "in" and therefore it will allow the voltage across itself to change almost like an open circuit. An ideal LTP design wo...
- Tue Jan 31, 2023 6:22 pm
- Forum: Technical Discussion
- Topic: Are carbon films worth the trouble?
- Replies: 137
- Views: 23935
Re: Are carbon films worth the trouble?
Sorry, my bad.dragonbat13 wrote: ↑Mon Jan 30, 2023 11:51 pm Not wanting to use carbon comp at all. Carbon film if not metal film.