EZ1084EQ NEW BATCH COMING - SEE MY MARCH 27 COMMENT ON PAGE 38

[Bluzzi]

Hi!! Just wanted to say thanks for this great Project! I finished my stereo set in one of the new Dan´s stereo cases and it sounds amazing! I used a little Sunpowers SMPS as suggested by Dr_J and it works, makes no noise that I can hear by normal use, fits in the case and is also a cheap option. Really happy with it.

You're welcome! Great to hear another baby is born! Twins this time!

Do you have the model of the power supply you used? I am testing some here so I can recommend them. Didn't think of mounting in the case itself but it seems some are reporting OK results. I'll have to test that myself.

Thanks

Cheers

Jim

 

[Floti]

Sure! Mine is this one: https://www.conrad.de/de/acdc-einbaunetzteil-sunpower-sps-035-24-24-vdc-15-a-35-w-510374.html

 

[Bluzzi]

Sure! Mine is this one: https://www.conrad.de/de/acdc-einbaunetzteil-sunpower-sps-035-24-24-vdc-15-a-35-w-510374.html

OK thanks. Very similar to the one I am testing. Yours is actually a little smaller even.

Cheers

Jim

 

[Floti]

Hi! I also tried this one and works aswell. It´s even cheaper! https://www.conrad.de/de/acdc-netzteilbaustein-geschlossen-mean-well-rs-35-24-24-vdc-15-a-36-w-1297300.html

 

[Greg S.]

Please never ever use those switching PSU crap! I did once and had a lot of trouble..
I designed my own PSU-PCB and I got -120dBV Ripple and Noise out of my Box delivering 24VDC(<100kHz)!

 

[weiss]

Hi! I also tried this one and works aswell. It´s even cheaper! https://www.conrad.de/de/acdc-netzteilbaustein-geschlossen-mean-well-rs-35-24-24-vdc-15-a-36-w-1297300.html

Hey Floti, great discovery!!
i'm also gonna build a stereo matched 1084 with added 1290 boards. What front panels did you guys use? can't decide between two 1U or one 2U version...

 

[Bonsaimaster]

Ok I have a problem with one of the boards I built. The unit sends signal with the IRON and BYPASS but with the EQ engaged I have to turn the gain all the way up to barely hear it. Then when I switch back to IRON the unit is loud and distorted. Any ideas. I re soldered everything but no go.

Thanks

 

[Colorblind]

Hey all,

I built a couple of these units awhile back and I've used them a ton, but have not gotten around to biasing them. I'll be using the standard Pro Tools signal generator to feed a 1k sine wave into the EQ. I've got a B&K 1477 Oscilloscope that I'm going to attempt to use as well.

My question is, where do I connect the oscilloscope to? The build guide says to connect to the EQ output, but the output is a 3-pin XLR, and the oscilloscope is just a single probe. I did some research but haven't found a clear answer yet. Any help would be much appreciated!

C

 

[Colorblind]

Anybody? 

 

[shabtek]

connect the scope across the output transformer secondary

 

[Colorblind]

connect the scope across the output transformer secondary

Ok, so if I understand correctly, the Carnhill 1847's secondary wires are blue, green, black & violet. Do I need to connect the scope to all four, or a pair, or just one?

Thanks,

C

 

[shabtek]

Scope probe to xlr 2 and  scope ground clip to xlr pin 3

 

[Colorblind]

Thanks. I bought my scope used and the probes didn’t come with ground clips, which added to my confusion!  Going to track one down.

 

[Leesecho]

Long time reader, first time post... Does anyone know if the ez1084 PCBs will be made available to buy again at some point? Should I reach out to Bluzzi directly? Thanks, and any help is appreciated!

 

[zqone537]

Hey good folks,
I am having an issue with my 1084 eq and eas hping you could help me out. It has been working great for me just so you know, Absolutely love this eq. So I go to use it the other day and the output is really low. When I have the gain knob cranked all the way up to max. In hard bypass, normal bypass and engaged. Any clues as to what I can do to fix her up? Thanks for all you time.
Zq

 

[3nity]

hi ZQ.
How did you achieve hard bypass..the answer lies there...because you are completely bypassing the whole eq and still you got low output.
i would check your signal source as well as check for cold solder spots.
thanks

 

[zqone537]

I'm such a nub! That was exactly it 3nity! Bad channel on the patchbay. Now I can have a pair. I'l be reaching out to you soon bro. Thanks a bunch!

 

[fragletrollet]

Came over a cool read:

An example of a system whose controls interact is the Neve 1073. In the 1073, the high- and low-frequency equalization sections are implemented as active filters within the same gain stage. Figure 9 shows the high-frequency responses of the EQ with the low-frequency selector at "Off" (blue), and the same responses with the low-frequency selector at 220 Hz (red). Even though there is no low-frequency boost or cut being applied, the character of the high-shelving filter is influenced by the low-frequency selection. This behavior makes the high-filter more flexible, because different behavior can be coaxed out of it with different settings applied to the low-frequency selector.

I wasn't aware of this! source

Still loving these eq's! Have a couple of 1073 addon eq's for my 1073 line-amps, and as I love the 10k setting on my 1084's, I was interested in finding the cap responsible, so I could try out something closer to the 10k hZ of the 1084 opposed to the 12k on the 1073. Well, looking at the schematic, there is a bit more going on than a simple RC or LC setup! Seems like it's combined with the LF shelf, and I have no clue as to what online filter calculator I should use to find a new cap... and not alter anything else!

In terms of a rerun; would be really cool with a frontpanel design for vertical use, mounting something close to a 19" panel vertically to resemble channel strips on a mixer. Preferrably with the 500 series width! Anyhoo... all the best to you Bluzzi!

 

[Bluzzi]

Sorry just saw this. Glad it was sorted out. Thanks to 3nity for suggestions.

Came over a cool read:

I wasn't aware of this! source

Still loving these eq's! Have a couple of 1073 addon eq's for my 1073 line-amps, and as I love the 10k setting on my 1084's, I was interested in finding the cap responsible, so I could try out something closer to the 10k hZ of the 1084 opposed to the 12k on the 1073. Well, looking at the schematic, there is a bit more going on than a simple RC or LC setup! Seems like it's combined with the LF shelf, and I have no clue as to what online filter calculator I should use to find a new cap... and not alter anything else!

In terms of a rerun; would be really cool with a frontpanel design for vertical use, mounting something close to a 19" panel vertically to resemble channel strips on a mixer. Preferrably with the 500 series width! Anyhoo... all the best to you Bluzzi!

Thanks for the kind words. You can always just make your own panel. You would only need to redesign the labels, everything else can remain as is.

I thought if a 500 series design and it is possible but didn't get around to it. Who knows if there is enough demand I may do it.

Nice to hear the EQ is still getting LOVE !

 

[TheseGoToEleven]

Came over a cool read:

I wasn't aware of this! source

Still loving these eq's! Have a couple of 1073 addon eq's for my 1073 line-amps, and as I love the 10k setting on my 1084's, I was interested in finding the cap responsible, so I could try out something closer to the 10k hZ of the 1084 opposed to the 12k on the 1073. Well, looking at the schematic, there is a bit more going on than a simple RC or LC setup! Seems like it's combined with the LF shelf, and I have no clue as to what online filter calculator I should use to find a new cap... and not alter anything else!

In terms of a rerun; would be really cool with a frontpanel design for vertical use, mounting something close to a 19" panel vertically to resemble channel strips on a mixer. Preferrably with the 500 series width! Anyhoo... all the best to you Bluzzi!

You might take a look at the 1066 schematic, as it is quite similar to the 1073 but has its high shelving at 10k instead of 12k.

The B205 subcircuit in those units is a sort of active variation of the James (which has 2 caps for bass and 2 more for treble). There is a version of that for simulation over at “TSC in the Web” which was added a little while back.

Active James w/ dual bass caps

However, the B205 has at least 6 caps involved so the Neve really needs to get its own simulation over there.

I noticed that on the B205, the R’s on the treble side are 620 ohms on the 1073, instead of 1.2k on the 1066. The R’s on the bass side are different too, but that’s probably only to match the change in the bass pot (47k to 50k.)

The caps are exactly the same in the 1066 and 1073 shelving high/low section, at least according what I see on their schematics.

Edit: I see on other sites that some 1066 owners find a B180 card inside instead of B205. A picture of that B180 card shows it has the all the same cap values as the B205 in the 1073 with the exception of a pair of 33nF instead of a pair of 22nF. But other 1066 owners report B205's inside with a 22nF pair on them, which matches the schematics. Curious.