Thanks for the replies. I changed the power tubes (EL34) to the opposite sides and the problem persists. It might even be that the distortion can be eliminated by having the bias all the way up and having the red light solid constantly, but I am worried this may be bad for the amp. Any other suggestions? I tried another speaker, a cheap one that I assume is easier to push, and it doesn't change the problem, so I am guessing it is not related to the speaker being to difficult to push, but an amp problem.
TLS49, from what I have read, you are totally correct about he SL6's. It is interesting that when he bought this setup years ago at a high end hi-fi shop, this setup is what they recommended. Part of the reason I was thinking of selling this combo is it just doesn't sound good, but now I realize it is probably just the speakers being mismatched with a low power amp. Thanks for confirming that.
Jond: I don't think he has ever changed the tubes. Although he has probably only had the amp on maybe 100 hours over the last 10 years. So the tubes probably just all need to be changed, unless time doesn't affect them, and only usage.
Thanks for your ideas. If you have any more about where to proceed with the bias light, or whether I should even worry about it, all is welcome. Thanks for your time.
R |
So switching out the tubes didn't change the red light which stayed on in the V7 position, regardless of the tube placement. There are not other red lights or "fuse out" indicator lights on. I think I read something on another forum about a "plate fuse", but I can't be sure that was what was mentioned and I can't find the thread again.
I will give a call to CJ tomorrow. I'm sure it will cost a fortune just to ship that beast. I see some upgrades on their page, anything you recommend if I send it in.
As far as the SL6's, I think I will list them on here or on Ebay. I have enough speakers and if I keep the amp I will want to take that money and use it on a speaker set that matches the amp better, or to help offset any repair costs. Thanks again for all your advice.
R |
OH damn. They are at the CES show all week. :( Have to wait until next Monday to get any answers. |
Still waiting on a call from CJ. I went to a local shop ( UTAH) and they said CJ is a company that doesn't give out schematics so they can't work on it and I have to send it in. :( The local owner recommended the Mullard EL34, and I have recommendations for the Genalex Gold Lion KT-77 and the JJ E34L. Is it really going to sound different with these different tubes, and if so, should I just roll the dice, or do any of you vets have experience with all three of these recommendations and can offer me some advice. Lastly, I think these tubes are all original and probably have never been replaced, although the amp has only been used less than 100 hours during that time. Do tubes degrade, and if so, should I just do a mass exchange of all the tubes?
JAZZONTHEHUDSON: What do you mean by "rolling the line stage tubes"?
I did try the SL6's in a solid state setup, and they sounded fine. Not as good to me as the mid-to-hi-grade RBH I was comparing them to. But with a solid state and my record player, it was nice. Might keep them just for retro sake. |
A rep from a tube store wrote me and here is what he had to say about a few tubes I was looking at.....
"The EL34 is a pentode. A pentode has a suppressor grid in addition to the control grid and screen grid. The power pentode was developed by Philips in the 1930s. RCA developed the beam tetrode which has a set of beam plates instead of the suppressor grid. At the time Philips held the patents on the power pentode anyone who wanted to build power pentodes had to pay Philips to obtain licensing to build them. RCA developed the beam tetrode so they could build tubes that functioned like a power pentode and not pay the licensing fee. The 6L6 was one of the first beam tetrode tubes. Compared to the EL34 pentode, the 6CA7 and KT77 beam tetrodes will have a little more bass response and sound warmer." |
It has been a crazy holiday season for us. Finally just decided to stop trying to research all of the other tubes as well and just ordered some
JJ E34L's. I was up late last night trying to find some 12au7 and 12ax7, but started getting pricey since I don't know if the amp will need a major overhaul yet and I read that if I send in the amp for upgrades, often times they replace your tubes for you. So, waiting to buy other tubes but the EL34's should be here shortly and I'll see what they do. I am not hopeful it will fix the problem and not looking forward to shipping that beast to C&J. I noticed some fuses (auto looking, blade-type) under the hood and behind the EL34's, so maybe I'll take a look at those today and make sure they aren't blown.
If I keep the amp, which I probably will, I need to start looking for a great pair of speakers for them. I know Klipsch are super efficient, but typically too bright for me. I have seen several reviews and blogs about good speakers for them, so I'll probably start that search as soon as I test the EL 34's. $$$$$ It's always about the cash. Boo for not being rich. haha.
You all have been very helpful. I'll keep you updated. |
The tubes arrived, I installed them, let them warm for an hour, biased, then turned on some music. And.....the problem may be fixed. So, interesting thing when taking out the old tubes. All of the tubes had no markings on them but one, which read EL34G. That tube was in the paired channel where I was having the problem, though in a different socket. I only change the "bad socket" with another tube from the other channel, but never changed out that EL34G tube. It seems strange that a neighbor tube, in the same channel, could have been causing the bias light to light up and stay on its sibling tube, but that seems to be the case. So... now I have to find some amazing speakers to try out. Any suggestions for something that isn't super bright, has a high sensitivity and doesn't cost over, say $800? I know that isn't a huge budget. Thanks again for all your help. I have the old RBH speakers hooked up now and the sound pretty good. I have a call into RBH and have sent them pics so they can give me the model number and specs. They are old. No markings. I'll keep you posted.
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Found out the info on the RBH’s built in 1993. 2 pairs, but I am listening to the larger model, the 812. The smaller speakers that match it are the 63’s. Here are the specs:
Specifications for 812: System Type: Acoustic Suspension 2-Way Woofer: 8" Long Throw Polypropylene Tweeter: 1" Liquid Cooled Polydome Tweeter Protection: Poly Switch Controls: Constant Impedance Tweeter Output Crossover (’ Frequency: 3COOHz. Attenuation Rate: 24 db/Octave & 12 db/Octave Asymmetrical Recommended Amp: 20 to 150 Watts (unclipped) System Impedance: 8ohms Frequency Range: 45 to 22,COO Hz Efficiency (SPL): 89db Cabinet Finish: Real Walnut, Oak and Black Oak Veneers ~aker nnection: 4-Way Gold Plated Binding Posts Cabinet Dimensions: 19" H X 12" w X 10.5’’ D Weight: 33lbs. each
and the 63’s: System Type: Acoustic Suspension 2-Way Woofer: 6" Long Throw Polypropylene Tweeter: 1" Liquid Cooled Polydome Crossover Frequencies: 3000Hz. Attenuation Rate: 12 db/Octave & 6 db/Octave Recommended Amp: 5 to 80 Watts (unclipped) System mpedance: 8ohms Protection: Poly Switch Protection Circuit Frequency Range: 60 to 22,000 Hz Efficiency (SPL): 89db Cabinet Finish: Real Oak and Black Oak Veneers ~aker nnection: 4-Way Gold Plated Binding Posts Cabinet Dimensions: 12" H X 8" w X 7" D Weight: 10 lbs. each ShipQing Weight: 25 lbs. / Pair
I know it is hard to tell much from stats, but would a more efficient speaker be better suited, or is all I am missing out on is the ability to go loud? Right now I can the volume to about 45% before it starts to distort a bit. I wouldn’t mind a bit more volume. Wish I had some Klipsch laying around just to test them. |
Reading some reviews, here are some of the speakers tested with the system that people have enjoyed. It is an old amp and all of the speakes look 1985-2000 range. Maybe this will help keep the cost down, but I doubt it. Royal Reference 3A,
KEF 104/2,
Rogers LS3/5A speakers,
Totem Model 1 Signature,
Thiel 2 2's,
QUAD ESL 57's,
B&W N805s,
ProAc 2000 Signature speakers,
ProAc 2s,
ProAc response 1SC's,
B&W DM610
Anything new anyone would recommend? |
On another note, I am getting a mid-grade record player fixed and the CJ doesn't have any phono plugs/ground. Is there an affordable solution? |
Also, BradwBradley, I see the sensitivity of the Kef LS50 is 85. Is that going to work well with my amp that doesn't put out a ton of power? |
So I am getting my record player back today. Should sound great. I am in need of a pre amp for it and wondering if I should go with a Tube Phono preamp and how that might interact with my CJ. Looks like they start around $180, whereas some of the SS ones go for $50. I would really like to keep it around $200, but willing to go more if the opinions are that it will make a big difference. |
Been researching a bit and this one looks promising for a reasonable price. Puffin Phono DSP. $399 . The
ART DJPRE II Phono Preamp Audio Interface gets good reviews for a $50 product, but it sounds like a lot are using it on basic equipment that just doesn't have a phono on it. |
Hi all, just bumping this. Been playing with the amp and different speakers and having a fun, interesting time experimenting. Just ordered some vinyl that isn't scratched, like most of my collection, but still need a pre- amp or some way to connect the record player as there isn't a phono input. Any suggestions?
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