Re: [AMRadio] 813 tx (EL-34 comment)
In a message dated 11/28/04 12:18:08 PM, [EMAIL PROTECTED] writes: Unfortunately, the audiophool community has got in on the action. People are paying top ridiculous dollar for EL-34's now. Last year at Dayton, someone bought an Apache transmitter at the flea market, paid the vendor's price for it on the spot, opened it and removed the EL-34 modulator tubes and left the rest of the transmitter at the vendor's booth. Must have been rare examples with just the right color brand name lettering or some other premium technical characteristic. Just checked and lots of these tubes currently being offered for reasonable prices on the e-place . The EL-34s are good tubes. Couple of these will put out a lot more audio running AB1 than a pair of 807s. Swapped a pair into a Viking 2 a while ago and eliminated many of the well known audio shortcomings found in the stock version of that rig. Dennis D. W7QHO Glendale, CA
Re: [AMRadio] 813 tx (EL-34 comment)
On 28 Nov 2004 at 15:43, [EMAIL PROTECTED] wrote: The EL-34s are good tubes. Couple of these will put out a lot more audio running AB1 than a pair of 807s. Swapped a pair into a Viking 2 a while ago and eliminated many of the well known audio shortcomings found in the stock version of that rig. I am not sure how you quantify a lot more audio, but we probably could not hear the difference unless you could squeeze at least an extra 25-30 watts out of them, and even then it would be barely perceptible. My guitar amplifier with four EL34s is barely louder sounding than my other guitar amplifier with four little EL84s in it! The tone is not as good, and it only really sounds louder on the lower registers. 30 watts versus 100 watts is not that much when it comes to audio. It certainly doesn't sound 3 times louder! Not even close.
Re: [AMRadio] 813 tx (EL-34 comment)
In a message dated 11/28/04 1:12:38 PM, [EMAIL PROTECTED] writes: I am not sure how you quantify a lot more audio, but we probably could not hear the difference unless you could squeeze at least an extra 25-30 watts out of them, and even then it would be barely perceptible. Guess you've had no experience with a Viking 2. Stock, these run a pair of 807s AB1 in the modulator which just barely puts out enough audio to fully modulate the rig, even with a pair of hot tubes and the screen voltage and grid bias adjusted just so. More typically one gets flat-toping and distortion. One way to solve this problem is to modify the rig to add a proper AB2 driver (6AQ5 with negative feedback, etc.) along with regulating the screens and bias supplies. Dropping in a pair of EL-34s works just as well and is an easier mod. Never measured just exactly how much more headroom the 34s provide, but one can definitely hear the difference (believe me). Dennis D. W7QHO Glendale, CA
Re: [AMRadio] 813 tx (EL-34 comment)
Hello Dennis, From working with many EL-34 based amps from Guitar to HIFI I would have to agree with you. Just look at the cathode area and size of the plates. While I don't have the technical reference to back me up, there's a direct correlation between the size of the Plate/Cathode area and a nice sound. Higher peak current capability? Density? Who knows. I have yet to hear any small internal tube sound big and fat. Most noticeably with the later 12AX,U 7's. A NOS large plate,while supposedly the same parameter tube, sounds much fatter than a later,much shorter box plate. El-34's are known for their higher even harmonic distortion which is why they work so well on guiter. EL-84's in the same way have an even higher even harmonic level which makes amps using them sound way louder for the watts. Vox AC30 for examp. I will have to try the EL34's in my VK 2 since direct driving the grids of the 807's with a UTC line to grid transformer of appropriate ratio and op level just doesn't quite cut it either. There's also the fact that the 807-6L6 family of tubes are beam power tubes and an EL34 is a real Pentode. Enjoy! Wm. Courtright KB3DKS/1
Re: [AMRadio] 813 tx (EL-34 comment)
On 28 Nov 2004 at 19:02, [EMAIL PROTECTED] wrote: Hello Dennis, From working with many EL-34 based amps from Guitar to HIFI I would have to agree with you. Just look at the cathode area and size of the plates. While I don't have the technical reference to back me up, there's a direct correlation between the size of the Plate/Cathode area and a nice sound. Well, 813s out to sound really magnificent then! Niceness is hard to measure.
