Tubes and cats
- Thread starter RayP
- Start date
A followup ( or regurgitate ). While I was away travelling recently there were house sitters in our house. I had an old receiver hooked up to a pair of speakers that were more visually appealing than my usual monsters. I haven't got around to changing back and yesterday the cat barfed on the receiver and managed to kill it off. Some vomit fell onto the end of one of those ribbon cables and appears to have shorted out the power supply.
The cat survived. The vomit landed on the top of the case and then dribbled through the ventilation holes, a two step process which effectively insulated the cat. Getting back to my original question about a design to cat proof an amplifier, this looks like a possible technique.
ray
The cat survived. The vomit landed on the top of the case and then dribbled through the ventilation holes, a two step process which effectively insulated the cat. Getting back to my original question about a design to cat proof an amplifier, this looks like a possible technique.
ray
aragorn723
New member
Grainger49 said:
I have a cat who throws up almost every day. There is a cat food that helps with this kind of stomach issue, it's called Purina One Sensitive Systems. Maybe you can try that with your cat
http://www.amazon.com/Purina-One-Sensitive-Systems-7-Pounds/dp/B0002MLAEQ/ref=sr_1_2?ie=UTF8&qid=1388455036&sr=8-2&keywords=purina+sensitive+systems
Grainger49
New member
The two current cats only throw up infrequently. But our last cat was on the Purina One for the last 5 years of her life. Very good food for a sensitive stomach.
Don't mean to sidetrack the thread, but might help to have your cat tested for feline thyroidism. We fed ours the Purina kibble mentioned for many years and he puked almost every day. Vet ran some blood tests and diagnosed thyroid issue from poor diet (and way way too many treats). Had to switch to special diet kibble and wet food ($$$) from the vet, but he's puked once in the last 9 months. And is less nervous in general. Remarkable change in behavior. I still want to kill the f'er, but for many other reasons...
Yes, thyroid appears to be the problem. Catty-watty is on a special diet ($$$) and it seems to work for a while and then not, like a bad solder joint.
She also has the loud yeowly meow which interferes with the music during the day and sleep at night. It's amazing the volume that can come out of a small cat. Fortunately I am retired so the noise doesn't bother me too much.
I think she is deaf in one ear. I snapped my fingers on either side of her head and she only turned one way. I suspect it would be difficult to determine if she is losing the high frequencies.
If this all sounds a bit facetious, I can remember going to my father's house a year before he died and listening to his hi-fi system. Most of the music was coming out of one speaker and I realized that he had gone deaf in one ear. Occasionally I use a tone program to test my high frequencies and the results are getting quite sobering. 13k for me.
http://www.audiocheck.net/audiotests_frequencycheckhigh.php
ray
She also has the loud yeowly meow which interferes with the music during the day and sleep at night. It's amazing the volume that can come out of a small cat. Fortunately I am retired so the noise doesn't bother me too much.
I think she is deaf in one ear. I snapped my fingers on either side of her head and she only turned one way. I suspect it would be difficult to determine if she is losing the high frequencies.
If this all sounds a bit facetious, I can remember going to my father's house a year before he died and listening to his hi-fi system. Most of the music was coming out of one speaker and I realized that he had gone deaf in one ear. Occasionally I use a tone program to test my high frequencies and the results are getting quite sobering. 13k for me.
http://www.audiocheck.net/audiotests_frequencycheckhigh.php
ray
tuffy_puppy
New member
maybe a year ago our local power company came by and replaced every one of our lightbulbs with the new flourescent types. this led to our having an ABUNDANCE of the old type bulbs. set up a cheap gooseneck lamp that is always on. cat never even considers any other venue. good kitty!!!!!!!!!!!!!
Oberst Oswald
New member
13k for me also... 61 yrs.
Be careful using these website high frequency hearing testers (in assuming you get a accurate result). I tried them too and ended up hearing 13k too. I was curious, because when I was much younger I maxed out the system, hearing 22k (I told them I wouldn't hear the next tone anyway) the testers where amazed. I suspected that my computer was limited to that frequency, since the tones prior to me not hearing them, were clearly audible. I downloaded test files and listened to them through my bottlehead gear and I could hear up to 16k, still not bad.
mcandmar
New member
Interesting, i've done some tests myself and found my high limit is somewhere between 16-16.5k which i think is ok for someone in their late 30's. Low limit was always 20hz until i bought the S.E.X. amp, i can clearly hear down to 10-12hz now which was a surprise, i had honestly never heard anything that low before using my other headphone amps.
lol
There is a new piece of gear here at work, the yonsters cringe during a certain function. I hear somthing but its not annoying. and others hear nothing. I used a spectral analyzer (on a samsung 10.1 for what that is worth) and there is about a 90dB spike at 18k. I tell the youngsters that they won't be hearing that for long.
There is a new piece of gear here at work, the yonsters cringe during a certain function. I hear somthing but its not annoying. and others hear nothing. I used a spectral analyzer (on a samsung 10.1 for what that is worth) and there is about a 90dB spike at 18k. I tell the youngsters that they won't be hearing that for long.
Grainger49
New member
I worked at a stereo shop in my late 20s that used ultra sonic motion detectors. The frequency was 19,500 Hz. Fred Pinkerton would come in, unlock the shop and start cleaning up. I'd come in and all but be knocked to my knees. It would shake my fillings out.
Then Fred would look at me and say, "Oh, I left the motion detectors on again, didn't I?"
Those days are long gone.
Then Fred would look at me and say, "Oh, I left the motion detectors on again, didn't I?"
Those days are long gone.
They had those in my high school. I had to avoid certain stairwells where they seemed to always leave them on. I sure couldn't hear them today. My top end dimished after many years working in front of commercial ovens. The fan noise isn't that loud, but it's constant and I suspect it contributed to a loss above 14K I noticed when I was in my late 30s.
A lot of guys in the audio industry will refuse to admit to that top end loss. Unfortunately for them I happen to keep test tone tapes around. "Yeah, that's 15K. Yes it's playing, look at the meter."
A lot of guys in the audio industry will refuse to admit to that top end loss. Unfortunately for them I happen to keep test tone tapes around. "Yeah, that's 15K. Yes it's playing, look at the meter."
Back to the vomit and yes, the cat is still alive.
I've just got a 6E5P - 6C33C parafeed amp going and I think I have it sufficiently cat proofed.
The wire trays came from Ikea I think and I have cut out some holes for the 6C33Cs which are mounted above the plywood top to help dissipate the heat. I am using a 100 watt 1k resistor as plate load for each channel so that is mounted on top between the two output tubes. The 400 ohm bias resistors are mounted on the aluminium plates. There is not too much heat producing stuff under the top board. The output transformers are THP-60 Tannoy line transformers that can be configured as 650 : 8.
I've never tried these tubes before so I have not done anything too fancy such as fixed bias. Surprisingly when I eventually got it working the voltages were within a couple of volts of what I expected. Naturally they have moved a little but it all appears to be stable now. It's a pretty decent amp and hopefully it will work when we hold our next Bottleneck meet which we think will be on one of the last weekends in February depending on the weather.
Getting back to the cat. She hopped up to take a look and you could almost see her thinking 'What the hell is this?'. She sniffed a little and went to sit on the laptop which is my music server.
ray
I've just got a 6E5P - 6C33C parafeed amp going and I think I have it sufficiently cat proofed.
The wire trays came from Ikea I think and I have cut out some holes for the 6C33Cs which are mounted above the plywood top to help dissipate the heat. I am using a 100 watt 1k resistor as plate load for each channel so that is mounted on top between the two output tubes. The 400 ohm bias resistors are mounted on the aluminium plates. There is not too much heat producing stuff under the top board. The output transformers are THP-60 Tannoy line transformers that can be configured as 650 : 8.
I've never tried these tubes before so I have not done anything too fancy such as fixed bias. Surprisingly when I eventually got it working the voltages were within a couple of volts of what I expected. Naturally they have moved a little but it all appears to be stable now. It's a pretty decent amp and hopefully it will work when we hold our next Bottleneck meet which we think will be on one of the last weekends in February depending on the weather.
Getting back to the cat. She hopped up to take a look and you could almost see her thinking 'What the hell is this?'. She sniffed a little and went to sit on the laptop which is my music server.
ray
Grainger49
New member
Awesome. Some years back I bought a pair and, it seems, two pair of sockets. Using them in SET Parafeed seems perfect.
PB has fooled around with them too. His avatar (I think it is current) shows the amp.
PB has fooled around with them too. His avatar (I think it is current) shows the amp.
Holy cow, are you running 800mA per tube?
Good lord no! I'm running the standard 200 volts, 200 ma with a bias of 80 volts. Since I had read that the 6C33C is somewhat variable, I decided to put two permanent meters for each channel's bias as well as one for B+ so that I could monitor what the voltages were on a regular basis.
The photo shows one of the bias meters with the reading of 80 indicating roughly 80 volts. The meter is a 1 ma meter
http://www.allelectronics.com/make-a-store/item/pmd-1ma/1-ma-dc-panel-meter/1.html
For the bias meters I hook them up with a 100K resistor between the meter and the cathode of the 6C33C and the other side of the meter connects to ground. For the B+ I use the same meter but with a string of resistors that add up to 1 meg. I allow 100 to 150 volts for each resistor so in this case I just have five 200k resistors. The B+ meter reads approximately 48.
B+ is 480.
The drop over the 1K resistor is 200.
The drop over the plate is 200.
The bias is 80.
I apologize for the confusion.
ray
The photo shows one of the bias meters with the reading of 80 indicating roughly 80 volts. The meter is a 1 ma meter
http://www.allelectronics.com/make-a-store/item/pmd-1ma/1-ma-dc-panel-meter/1.html
For the bias meters I hook them up with a 100K resistor between the meter and the cathode of the 6C33C and the other side of the meter connects to ground. For the B+ I use the same meter but with a string of resistors that add up to 1 meg. I allow 100 to 150 volts for each resistor so in this case I just have five 200k resistors. The B+ meter reads approximately 48.
B+ is 480.
The drop over the 1K resistor is 200.
The drop over the plate is 200.
The bias is 80.
I apologize for the confusion.
ray
Ah, whew, I saw that ammeter and just had to ask!
I run mine at about the same operating point, though I think it's something like 210V/250mA.
A lot of forum posts discuss how inconsistently these tubes bias, and how variable the idle current is, but this has been far from what I've observed. At 250mA, I might see the bias wander by 1/2 a mA one way or the other.
If you are enjoying the amp, the Magnequest BAPC is a nice load for a 6C33 parafeed.
-PB
I run mine at about the same operating point, though I think it's something like 210V/250mA.
A lot of forum posts discuss how inconsistently these tubes bias, and how variable the idle current is, but this has been far from what I've observed. At 250mA, I might see the bias wander by 1/2 a mA one way or the other.
If you are enjoying the amp, the Magnequest BAPC is a nice load for a 6C33 parafeed.
-PB
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