I received and installed the replacement stock value RIAA components. When I powered it up, the left channel hummed badly.
After several go-rounds of disassembly, inspection (I found a suspicious solder joint) and reassembly I still could not find the trouble so I decided to remove all of the bypass caps.
The issue is now resolved. The stock RIAA network sounds much better than the "optimized" values that I tried. The better parts sound a bit cleaner and clearer but the better coupling caps were a much bigger change. In fact, I doubt that I would be able to hear any improvement from the RIAA parts with the stock coupling caps.
I also build a bucking transformer into a power cord. I used a Hammond 166N6 6.3 volt transformer which drops my 122 wall voltage to 115. The higher voltage wasn't really an issue but it is right on spec now.
Pete
After several go-rounds of disassembly, inspection (I found a suspicious solder joint) and reassembly I still could not find the trouble so I decided to remove all of the bypass caps.
The issue is now resolved. The stock RIAA network sounds much better than the "optimized" values that I tried. The better parts sound a bit cleaner and clearer but the better coupling caps were a much bigger change. In fact, I doubt that I would be able to hear any improvement from the RIAA parts with the stock coupling caps.
I also build a bucking transformer into a power cord. I used a Hammond 166N6 6.3 volt transformer which drops my 122 wall voltage to 115. The higher voltage wasn't really an issue but it is right on spec now.
Pete
You are not the first that I have read that the "Optimized" parts upgrade didn't sound better and they went back to the stock. You did buy a brand new EAR 834P Clone from Zero Zone correct? If so, that's the one I bought and before I did any upgrades I hooked it up and made sure there was no humming from the unit and listened to it for a few days before diving in.
The humming I did get was not from the EAR Clone but from 3 other external source which I eliminated and not it's really quiet at high Volume levels.
I always start with the Coupling caps first and then listen for a few days before moving on. In stock form it was quiet and I didn't see any need to even try those "Bypass" caps. I saw them when I was doing the bare board assembly in the Lenco Heaven thread but skipped it.
So far the upgrade of the coupling caps with Mundorf EVO oil caps and the AudioCaps Theta has been a really big improvement over the stock version. I really like what I'm hearing with This Phono preamp and the Sumiko Amethyst cartridge, really nice sounding.
My next move will be the 33uF power supply caps on the PCB. I will upgrade them to 100uF Nichicon KX caps. I also have plans for the Power supply caps in the enclosure with the transformer, but I want to listen first after the 100uF cap upgrade. I don't want to loose the basic EAR 834 sound that we are love so much and why we bought this Phono preamp.
I will be making a Bucking Transformer for this unit but after I power up my system with the Tube preamp and power amp my line voltage is around 117-118V so that fine. I have one of those inline Voltage monitors so I can always see what the wall AC voltage is.
I hope you are enjoying your EAR clone now and enjoy listening to some wonderful music! Enjoy!
The humming I did get was not from the EAR Clone but from 3 other external source which I eliminated and not it's really quiet at high Volume levels.
I always start with the Coupling caps first and then listen for a few days before moving on. In stock form it was quiet and I didn't see any need to even try those "Bypass" caps. I saw them when I was doing the bare board assembly in the Lenco Heaven thread but skipped it.
So far the upgrade of the coupling caps with Mundorf EVO oil caps and the AudioCaps Theta has been a really big improvement over the stock version. I really like what I'm hearing with This Phono preamp and the Sumiko Amethyst cartridge, really nice sounding.
My next move will be the 33uF power supply caps on the PCB. I will upgrade them to 100uF Nichicon KX caps. I also have plans for the Power supply caps in the enclosure with the transformer, but I want to listen first after the 100uF cap upgrade. I don't want to loose the basic EAR 834 sound that we are love so much and why we bought this Phono preamp.
I will be making a Bucking Transformer for this unit but after I power up my system with the Tube preamp and power amp my line voltage is around 117-118V so that fine. I have one of those inline Voltage monitors so I can always see what the wall AC voltage is.
I hope you are enjoying your EAR clone now and enjoy listening to some wonderful music! Enjoy!
Those are the guys that I bypassed with 0.33uF film caps on the bottom of the board. I had hoped to avoid replacing them. This area seems like it could be easily improved.
What are your plans for the power supply board? I wonder if it would make sense to split the supply and increase the number of connecting lines, either by changing the umbilical cord or doubling up with a second 4-wire.
I ask because I think that I now have the makings of a nice sounding budget system, but with a little more work this might really be something.
Pete
"What are your plans for the power supply board? I wonder if it would make sense to split the supply and increase the number of connecting lines, either by changing the umbilical cord or doubling up with a second 4-wire."
I wanted to use some better Diodes along with better Caps. Sounds like you want to do a Dual Mono design now huh? 🙂 I also want to change out the RCA connectors cause I have some interconnects that slip off and those RCA connectors are not the best.
"Those are the guys that I bypassed with 0.33uF film caps on the bottom of the board. I had hoped to avoid replacing them. This area seems like it could be easily improved."
I haven't had really good results with by passing caps. I usually just get better caps. I do want to change the Plate resistor to how Allen Wright and Mike Elliott did with 2-3 resistors in parallel to make the same value as the the single resistor. Any benefits other than heat dissipation and current splitting?
"I ask because I think that I now have the makings of a nice sounding budget system, but with a little more work this might really be something."
Yes, these are very nice budget clones and sound awesome when upgraded properly. I also found out that this EAR 834P may have been a copy of someone else work as well with a few other parts changed. I look into the talk about the EAR being a copy of the Marantz Model 7 phono section. Almost identical to the Marantz Model 7. If you haven't seen it, check it out the schematics.
I don't want to do too much as I may loose that musical sound that it's so famous for. As of late last night I was starting to hear the Analog source side starting to change and soundstage getting deeper/wider. I really could stop but I was already playing music for at least 5 hrs. This is how good this is starting to sound just with the 3 changes I did.
I wanted to use some better Diodes along with better Caps. Sounds like you want to do a Dual Mono design now huh? 🙂 I also want to change out the RCA connectors cause I have some interconnects that slip off and those RCA connectors are not the best.
"Those are the guys that I bypassed with 0.33uF film caps on the bottom of the board. I had hoped to avoid replacing them. This area seems like it could be easily improved."
I haven't had really good results with by passing caps. I usually just get better caps. I do want to change the Plate resistor to how Allen Wright and Mike Elliott did with 2-3 resistors in parallel to make the same value as the the single resistor. Any benefits other than heat dissipation and current splitting?
"I ask because I think that I now have the makings of a nice sounding budget system, but with a little more work this might really be something."
Yes, these are very nice budget clones and sound awesome when upgraded properly. I also found out that this EAR 834P may have been a copy of someone else work as well with a few other parts changed. I look into the talk about the EAR being a copy of the Marantz Model 7 phono section. Almost identical to the Marantz Model 7. If you haven't seen it, check it out the schematics.
I don't want to do too much as I may loose that musical sound that it's so famous for. As of late last night I was starting to hear the Analog source side starting to change and soundstage getting deeper/wider. I really could stop but I was already playing music for at least 5 hrs. This is how good this is starting to sound just with the 3 changes I did.
The first coupling cap: the original EAR was 0.15u, the clone came with 0.12u. the board specifies 0.1u - 0.15u for that spot.
What effects does 0.1u vs 0.15u have on the overall freq response? Is it just a low freq rolloff? Or something more going on?
What effects does 0.1u vs 0.15u have on the overall freq response? Is it just a low freq rolloff? Or something more going on?
Mine came the same way, I just put the 0.15uf in with the Mundorf EVO Oil cap. The other coupling caps were AudioCap Theta 0.1uf and 1.0uf. The original design has 0.1uf first coupling cap, 0.1uf for the second, and 1.0uf for the last. But the Model 7 has 0.0uF, 0.1uF, and 0.47uf.
Also, re: bypassing the elecrolytic caps. I have never really understood that.
I kind of get it for signal path caps. Ideally, bypassing a bigger coupling cap would mean half the signal (above the rolloff point) goes thru the smaller nicer cap, and half thru the big cap. At lower frequency, past the small cap rolloff , it all goes thru the big cap. 50/50 is the best you can get there, and it doesn't seem to provide enough value to me.
For power supply rail caps and non-signal caps to ground, I just dont get it at all.
I kind of get it for signal path caps. Ideally, bypassing a bigger coupling cap would mean half the signal (above the rolloff point) goes thru the smaller nicer cap, and half thru the big cap. At lower frequency, past the small cap rolloff , it all goes thru the big cap. 50/50 is the best you can get there, and it doesn't seem to provide enough value to me.
For power supply rail caps and non-signal caps to ground, I just dont get it at all.
I love the the top of you case. That laser cut out "TUBE" design is awesome.
Using a Hammond Choke input on the power supply huh? Nice!
Did you upgrade any of the resistors in your build? Nice enclosure too!
By bypassing signal path caps wouldn't that create a phase shift? leading to what some say a smearing of the sound?
I don't know the answer to that question. I have no idea how to model phase performance from two different caps in parallel.
My first tube experience was with a Dynaco Stereo 70, probably 40 years ago. I got a working stock one and soon installed the GSI input board. I moved the power transformer to an external board and used a bunch of photoflash electrolytic capacitors in series/parallel banks to get the voltage rating.
It sounded ok, but I then bypassed the photoflash caps with a polypropylene (I think) film cap. The improvement was startling! The top end opened up dramatically and all of a sudden my system had a top octave.
Pete
Last edited:
Wow, beautiful!
I see that you have upgraded the electrolytic caps, both on the power supply board and the signal board. What are you using, and have you made any other changes? Diodes, for example?
Pete
I've never used photoflash caps. Wouldn't that be like using motor start caps vs the recommended motor run caps for a PS?