Any experience with EZ-80s, 5687s or Bendix 6900s?

I have an AMR CDP and it uses EZ-80s as rectifiers and 5687s in the output stage. I may have a problem with a rectifier tube and was thinking of replacing it (them). I know nothing about EZ-80s (or EZ-81s). The current rectifier is an NOS Philips. Does anyone here know what a Telefunken EZ-80 might sound like in this application or how it might compare to the Philips?

Also, I have heard that some people are using Bendix 6900s in place of the 5687 Tunsgarams. Same questions here if you have any input.


Sorry, I mixed these tubes up in my original post. The Phillips are the 5687s and the Tungsrams are the EZ-80s.
After this last weekend, the tube configuration on my AMR CD77 is Philips 5687 in the rear, Mullard CV4024 (12AT7) in the middle, and RFT EZ80 in the front. I have heard good things about the Bendix 5687, but haven’t had a chance to audition them. This past weekend I had some extra time compared four different sets of EZ80’s (front position).

Tesla – rolled off highs & lows; very warm; sounded like a screen was placed in front of the speakers. I was not impressed at all.
Brimar – similar to the Tesla, but not quite as warm and not as rolled off at either end. The mid-range is where these tubes excel.
Tungsram – great extension both top & bottom, but poor density. Music had a hallow sound, like listening through a pipe. Also has a bit of boost in the upper mid-range. I had used these previously, but was never happy with them.
RFT- Magic time! This is by far the best tube I have tried in this position. Voices are real; in the room with you real! Thunderous bass, excellent midrange and a delicate high end. If one can find fault with them, it would also be a bit of push in the upper midrange, but far less than the Tungsram. Mind you, I’m knit-picking (but isn’t that what we all do with this “hobby”?). I plan on adding a third set of damping rings to the tubes – my guess is that it will help control it a bit.

Remember, no tube is perfect. All have their strengths and weaknesses. What works in my system my not work in yours. You really have to experiment to find out what’s best for you. In my opinion, this is one of the great strengths of the AMR; you can customize it to your liking. Also, you can easily move the damping rings to different points on the tubes to make even finer adjustments to the sound. Additionally, if your machine is not a 77.1 (the current version), you can have Darren Censullo of Avatar Acoustics modify it to the new standard – a substantial improvement!
Thanks Kgproperties! You and I must have similar tastes. Your description of the Tungsram sound is exactly what I told Darren yesterday. I reviewed the original version of the AMR for Stereo Times and just had Darren send me the .01 update (with Tungsrams). I still have both players.

I am having a hard time finding the RFT EZ-80s. I have a friend loaning me some Telefunken EZ-80s and Bendix 6900s to try. It sounds like the RFTs may be what I am looking for from your description. Do you have any sources for the RFT EZ80s?


I have tried a bunch of EZ 81 rectifiers in my system and the old Mullards are King. The plain old RCA's are also very good and probably less rare and precious. Now, according to Cary, the EZ 80 is a direct drop in replacement for the EZ81's in their SLP 90 preamp. I am not sure however if we can assume that to be the case in all equipment and applications. Perhaps someone else out there could enlighten us on that question. I was told they have exactly the same electrical specs. What does the tube reference manual say?

Here is what I learned about the EZ81 as a drop-in for the EZ80. The EZ81q is pin-compatible but draws nearly twice the heater current (1.0A vs. 0.6A). I am not sure if the transformers in the AMR have enough capacity to take the EZ81 but I will try to find out.
Hi Frank:
I purchased the RFT's on ebay just a few weeks ago. The seller was/is "LCI_ELECTRONICS" (which looks to be the same seller as "ORPHEUS_2005", both located in Bulgaria. I purchased the RFT's & Tesla's from the same seller, and received both sets in just over a week from the payment clearance date! Go to ebay, and type in EZ80; he is still listing more of them for sale.

Please let me know how the Bendix 6900's sound in the AMR. I am very tempted to purchase a set, but at $600 a set...
Ken G.
Frank, here's an update for you:

I was fortunate to find a lightly used pair of Bendix 6900’s within 5 miles of my front door. The seller agreed to let me try them on the condition that I could return them to him if I was not happy with the sound. Upon replacing the JAN Philips 5687’s with the Bendix, any thought of returning them quickly vanished. From an already very quiet background, it is now even quieter. Voices (now) have a much more detailed, textured and richer quality – a “3-dimentionality” if you will. Lower mid-range is much fuller and layered than before. Bass response is also significantly improved. As with the mid/low-mids, bass has a fuller and richer presentation. As mentioned in my earlier post, changing the position of the damping rings on the tubes also allowed me to “tune” the tubes to my liking. The Bendix easily surpassed my expectations!
Thanks Kgproperties. I just bought the RFTs from him and they shipped yesterday. I also found an NOS set of Bendix Gold pin 6900s from a dealer and bought them. I'll keep you posted. I hope I get the same great results you did.!! ENJOY!
I use the 5687 Raytheon Cryo-Treated, not bad for the Sonics, tried the tungsol 5687 to warm for me...
Looking for the 'Bendix 6900 Red Bank'???

How did the 6900 tubes work out??
Glory, I've been away for quite a while and just happened to be researching tubes for my AMR again and saw your post. The Bendix were wonderful for a couple of months and then just crapped out on me.

I do not know if I was purposely sold old or defective tubes at the time (even though they were represented to me as NOS) or not. However, based upon subsequent dealings with that same dealer. I now consider him to be fundamentally dishonest.

Thus, I am now not sure if the tubes I had were representative of what an NOS Bendix really has to offer.

I am now open to suggestion as the AMR distributor screwed my player up when he upgraded it by taking out my double crown chip and never replacing it . Between that and the tube issues, I have never been able to get the real magic back with my AMR that it used to have. I now use it mainly for headphones and have since gone back to my Reimyo as my main CDP.


Hard for the B6900 to crap out. They run forever. Send them to me I will take them.
Brian Kyle of Xtreme AV in southern California sent you the Bendix 6900s on good faith that you would send him the money for them. I understand they were good and strong when he had them, yet only now the performance of the tubes is brought up. That aside, Brian contracted brain cancer not quite 3 years ago -- long after he sent the tubes, and his condition has deteriorated drastically to the point that he is now on daily hospice care, is unable to stand and walk, and may not be alive a month from now. So now "subsequent dealings" with him -- of which there were none -- and his integrity ("fundamentally dishonest") are called into question. Brian is incapable of defending himself due to his condition.

Did you purchase the Double Crown DAC chip from the distributor, whose reputation you impugn? What upgrades were performed? Any repairs? Where, and who paid for them and shipping?

People reading this can draw their own conclusions about ethics and integrity.

Why didn't you just send the tubes back for a refund? Seems like that would have made the most sense. Are you sure they were bad? Did you have them tested to be certain? That is what I would have done. Certainly a better option than trashing someone years later who has no opportunity to respond due to a chronic condition that will result in his death shortly. We all make mistakes but I certainly hope you realize your poor judgement at this time with your assertions as to Brian Kyle's character. IMO an apology is in order.

After hearing the story here I don't want the tubes even if they are perfect.

Let's see . repentence is in order I do believe.

Cut his family a check to rid yourself of the bitterness so you can live in freedom.
Apologies are very much called for by the two posts after mine. I also asked questions about your strong accusations of the distributor stealing "your" DAC chip and screwing up your player. Add to that the kicking of someone while he's down (permanently) while giving no proof of wrongdoing. And by your own admission you used tubes not approved for the player without checking, which likely may have "screwed up" your player -- not something covered by warranty. Fmpnd, it's time for you to man up, tell it like it is and accept responsibility, and make amends with the two people you have victimized, including a public apology here.
The OP must have checked out. Can't think of any other reason that an apology would not have been issued.
Considering he has been made aware of the replies, I am very disappointed.
Wow!!! Just saw this. As someone who has dealt with the Avatar US distributor on more than a few occassions I have to chime in and say the accusation that a former fighter pilot STOLE a chip out of a player he reps (the owner of Avatar Acoustics) who holds integrity sacrosanct is absolutely RIDICULOUS and defamatory!!! FRANK

You bought that unit at cost (as a reviewer) and got free upgrades... He has flown to your house and fixed your unit for free. You never bought that chip; when the unit used to have a socketed digital engine Darren comped you a double crown TDA board. When that boared failed and he fixed it for FREE (as he NEVER charged you for any repairs) the new boards were NOT socketed and he could NOT install another chip. So you got a free newer gen digital engine with a surface mounted chip. You should tell the truth and stop telling half truths!!!!!
Also he replaced the board IN YOUR HOUSE in your presence and he explained ALL this to you! You very well knew and understood all that was taking place. People like you take the fun out of this hobby. I hate dishonest people.