Hi everybody. I have an issue with my crack. For the past few months I have using it with 6080 and 5814 tubes. In that time I have installed speedball and update the output capacitors and installed a bypass on the last cap in the power supply. I used Mundorf Mkp 100uf 250V for the output caps and 2.2uf 250v for the bypass. Today I just got a NOS Chatham 5998. When I played some music I noticed that the volume was very very very low. I have to crank the crack to max just and I'm just able to hear sound. Could this be because of the output caps and the bypass. The rest of my tubes 6080's work as they should and I know the 5998 has different specification. So it is the tube or the crack?
Crack 5998 low volume
- Thread starter m17xr2b
- Start date
That's odd. I've done the same thing you have (replaced output caps and bypassed last cap on the power supply), and I'm also running a 5998. No problems at all. With 7 o'clock as my zero position, I usually listen around 9 or 10 o'clock. It sounds like your tube must somehow be bad, although I've never heard of the situation you're describing before. Try cleaning the pins on your 5998, and recheck your RCA connections.
Best regards,
Adam
Best regards,
Adam
m17xr2b said:
If every tube works except one, then the amplifier is working properly but the tube is not.
I forgot to say that it worked for the first ten minutes. In that time I felt that my tube search had come to an end. After that the left channel died and after and then the sound faded. I have to place the volume knob at half to just about hear some sound. I do hear both channel.
Paul Joppa
Moderator
If you want you can check the 5998 pin voltages - I expect pins 3 and 8 will be incorrect (too low) indicating an exhausted cathode.
Just got my replacement tube from tubemaze. While I did that I ordered another 5998 as a spare. Tested the tubes. I just have to mention that I did not receive 5998 but chatham 2399. So one tube has sound in only one channel. The other tube works good but my god it's microphonic. If i tap the table where the crack is very lite I can clearly hear it in the headphones. Also the microphonics do not start right away as I power on the crack but after about half an hour. The other tube that I use is a CBS 5814WA that I used for a while and I know it's not the culprit. I also noticed that the microphonic effect is intermittent. Is this a known issue with 2399 tubes?
I have not experienced that with any of my 2399s (or 5998s, which are identical).
I have run into a problem of my own. I was using a Bendix 6080WB and a Tungsram E80CC. E sound was perfect. Today, I received two G.E.C. 6AS7Gs I had been waiting for. The seller tested them at 102% and 104%, respectively. I pulled the 6080WB and inserted one of the G.E.C.s. The sound was very, very low and static-y. I let the tube warm up, but there was no improvement. So I pulled that tube and inserted the other G.E.C. Same problem. I figured I got a pair of bad tubes, so I decided to insert a 7236 I had and knew was good. To my surprise, I had the same problem: low, faint, scratchy sound. I pulled the 7236 and inserted a 2nd 7236. Same problem. Ten I swapped in the 6080WB I had been listening to. Still no improvement. I figured, "O.K., must be that the E80CC went bad." To I pulled it and inserted a spare E80CC. STILL NO IMPROVEMENT. WTF?!?!?
Anybody have any ideas what the problem could be? FWIW, the tubes are all glowing. I also hear sound in both channels, but both are low and scratchy. And last night everything sounded perfectly fine. What is going on?
I have run into a problem of my own. I was using a Bendix 6080WB and a Tungsram E80CC. E sound was perfect. Today, I received two G.E.C. 6AS7Gs I had been waiting for. The seller tested them at 102% and 104%, respectively. I pulled the 6080WB and inserted one of the G.E.C.s. The sound was very, very low and static-y. I let the tube warm up, but there was no improvement. So I pulled that tube and inserted the other G.E.C. Same problem. I figured I got a pair of bad tubes, so I decided to insert a 7236 I had and knew was good. To my surprise, I had the same problem: low, faint, scratchy sound. I pulled the 7236 and inserted a 2nd 7236. Same problem. Ten I swapped in the 6080WB I had been listening to. Still no improvement. I figured, "O.K., must be that the E80CC went bad." To I pulled it and inserted a spare E80CC. STILL NO IMPROVEMENT. WTF?!?!?
Anybody have any ideas what the problem could be? FWIW, the tubes are all glowing. I also hear sound in both channels, but both are low and scratchy. And last night everything sounded perfectly fine. What is going on?
AAAAAAAAHHHHHHHHHHHH!!!!!!!!!!
My cup of frustration runneth over. I took today off. My wife is out with the kids. My GEC 6AS7Gs finally arrived. I wanted to sit in my chair, put on my headphones, and relax in bliss while doing some reading. Instead I'm sitting here cursing the world. I love the Crack, but frankly this has been a frustrating process (none of which was due to the Crack per se). The stock 6080 was bad and i had to wait for a replacement. I later ordered a 5998 that turned out to be bad. I bought and struggled to install film caps, then spent many long nights trying to figure out what the problem with the film caps was before I found out one of the leads was bad. I had to wait for, and install the replacement. I wanted to upgrade the volume pot and because the wiring instructions on the sellers website were wrong, I miswired it, then stayed up all night rewiring it. Every time I need to do ANYTHING to the amp, I need to desolder and resolder my film caps. Now this. I know it is my fault because I keep trying to upgrade stuff, but it is getting to be a severe PITA. :-[
My cup of frustration runneth over. I took today off. My wife is out with the kids. My GEC 6AS7Gs finally arrived. I wanted to sit in my chair, put on my headphones, and relax in bliss while doing some reading. Instead I'm sitting here cursing the world. I love the Crack, but frankly this has been a frustrating process (none of which was due to the Crack per se). The stock 6080 was bad and i had to wait for a replacement. I later ordered a 5998 that turned out to be bad. I bought and struggled to install film caps, then spent many long nights trying to figure out what the problem with the film caps was before I found out one of the leads was bad. I had to wait for, and install the replacement. I wanted to upgrade the volume pot and because the wiring instructions on the sellers website were wrong, I miswired it, then stayed up all night rewiring it. Every time I need to do ANYTHING to the amp, I need to desolder and resolder my film caps. Now this. I know it is my fault because I keep trying to upgrade stuff, but it is getting to be a severe PITA. :-[
I figured you were going to say that. Ugh. That mean desoldering my film caps yet again. And with the speedball installed, accessing the terminals to test voltage and resistance is no minor task. Frankly, it makes me uncomfortable, since it is tough to see and I always fear I will short something...
