He-69 build/support thread. PCB's/kits-available!

[Igor]

Mm. Yep. Welcome to DIY EQ land!

 

[jandoste]

Hey Guys,
Did you try John Hardy 990c opams for this project?
Cheers

 

[StudioSQ]

I actually ordered the kit and it came without a front panel. Is is on the way in another shipment?

 

[Igor]

IMO, 990C should work, but better to run them at +/-16V.
Front panel: should come with kit. We had an overload with work, and, maybe, my assistant
forgot to ship it. Happens, human factor. Just let us fix it.
If something is missing: please mail me to igor_jazz at yahoo, will send ASAP.

 

[jandoste]

IMO, 990C should work, but better to run them at +/-16V.

Thanks Igor you told me that and had your great support on FB! just I wanted to know if someone already tried it...John hardy wrote me that 990C must work but I am not sure that is right
Anyway I am waiting my new op-amps
Cheers

 

[StudioSQ]

Just sent you an email abouy the pannels, thanks

 

[nielsk]

Since the HE opamp board was not included I guess I'll be sticking a 2520 in there, what are the TBD values for this?

 

[Grummy77]

Hi Igor.

I was hoping you could offer a little more info or guidance on the procedure to make the Transformer-less version. Forgive my lack of knowledge and understanding. I consider myself learning. 

I think I've been able to wrap my head around the differences in the input options from the documentation but I'm still a bit hazy on how I would implement the transformer-less output section. In the photos you supplied there seems to be a small PCB with what appears to be a DIP8 IC opamp in place of the LL1524. Is this something you offer separately? Is it needed for the tranny-less output option?

Basically the only detail I understand about the tranny-less output option is to add a resistor between TR+ & TR+2, and TR- & TR-2. I can't seem to find any onfo about that little PCB (in place of the output Tranny) in your tranny-less picture.

Any incite appreciated.
Cheers.

 

[nielsk]

Bump?

 

[nielsk]

Where does the other switch go and what does it do?
What is the deal with the Bypass 1,2 & 3 pads?
Any support at all on this thing would be appreciated.....

 

[ruffrecords]

The knobs are ELMA.
In Israel, they are available from local distributor (MOQ = 100+); in small quantities,
these knobs, usually in black, are available from Farnell.
10mm wing knob, 10mm knob, grey, without line, + black skirt with line, + black cap with line; 3.15mm shaft.

The great advantage of these knobs is they are available in sizes 9...45mm for every possible shaft,
can be stacked for concentric pots, can be used with skirt/pointer, etc. Excellent quality BTW.

http://il.farnell.com/jsp/search/browse.jsp?N=2017+202401&Ntk=gensearch&Ntt=elma+knob&Ntx=mode+matchallpartial

Hi Igor. I cannot see the 10mm wing knob at Farnell. There's a 14.5mm black one and a 21mm grey one. Which size did you use for this project?

Cheers

Ian

 

[zayance]

The knobs are ELMA.
In Israel, they are available from local distributor (MOQ = 100+); in small quantities,
these knobs, usually in black, are available from Farnell.
10mm wing knob, 10mm knob, grey, without line, + black skirt with line, + black cap with line; 3.15mm shaft.

The great advantage of these knobs is they are available in sizes 9...45mm for every possible shaft,
can be stacked for concentric pots, can be used with skirt/pointer, etc. Excellent quality BTW.

http://il.farnell.com/jsp/search/browse.jsp?N=2017+202401&Ntk=gensearch&Ntt=elma+knob&Ntx=mode+matchallpartial

Hi Igor. I cannot see the 10mm wing knob at Farnell. There's a 14.5mm black one and a 21mm grey one. Which size did you use for this project?

Cheers

Ian

10mm ones

Drop him a line:
https://sites.google.com/site/diypartsstore/catalog/catalog-page-2

 

[ruffrecords]

The knobs are ELMA.
In Israel, they are available from local distributor (MOQ = 100+); in small quantities,
these knobs, usually in black, are available from Farnell.
10mm wing knob, 10mm knob, grey, without line, + black skirt with line, + black cap with line; 3.15mm shaft.

The great advantage of these knobs is they are available in sizes 9...45mm for every possible shaft,
can be stacked for concentric pots, can be used with skirt/pointer, etc. Excellent quality BTW.

http://il.farnell.com/jsp/search/browse.jsp?N=2017+202401&Ntk=gensearch&Ntt=elma+knob&Ntx=mode+matchallpartial

Hi Igor. I cannot see the 10mm wing knob at Farnell. There's a 14.5mm black one and a 21mm grey one. Which size did you use for this project?

Cheers

Ian

10mm ones

Drop him a line:
https://sites.google.com/site/diypartsstore/catalog/catalog-page-2

Thanks for the tip.

Cheers

Ian

 

[nielsk]

Any      support    at  all??????

 

[Grummy77]

I've noticed on Igor's threads that he kinda comes and go's. It seems like he'll pop in when he's got time and answer a bunch of questions all at once. I'm guessing he's just busy right now.

This is one of his newer PCB's so I'm guessing that there aren't too many others that have experience with it. If there were we'd probably get some more discussion happening and end up answering our own questions.

 

[Grummy77]

I'll offer what little advise I can guess at until Igor returns. (keep in mind I'm pretty new to DIY)

nielsk - 2520 - Not sure about your TBD values for dropping a 2520 op-amp in. But if you're building the +-16v version you should have no problem using a 2520.

In my partial kits (I bought 2) I received a pair of Op Amp PCB's that I put together (I've yet to test them yet). Just in case I also purchased a pair of ML918 kits from Whistlerock http://www.whistlerockaudio.com/cart/index.php?main_page=product_info&cPath=35_39&products_id=106
and when building them I made the three resistor substitution to optimize them for +-24v. I did this because I plan to build the 51x version and run them off of 24v
Otherwise I've got some red dots, GAR2520s, and GAR1731s from CAPI that I could have used.

- Switch & bypass1,2,& 3. I could be wrong, but from what I can tell the Bypass (& preamp integration) switch connects to those three bypass pins. It looks like in the photos that Igor runs the wires and solders them from the backside of the PCB.

That's what I seem to gather anyway.


Unfortunately I'm still confused as to what the little PCB is in the outpu ;Dt tranny hole on the transformer-less version pics and whether I need whatever it is . Oh well I think I might just wait until I can afford the two Lundahl's. I seem to think I have a grasp on that option. Plus having some tranny's in there feels a little more bad ass.

 

[nielsk]

Thanks for you reply, Grummy... so it looks like I should have received the op amp board then.
I would sort of figure that, as the op amp would be a big part of what makes this different from all the other LCR eqs...
The pics in the download clearly show the pk/th switch wiring from every angle imaginable, but I find nothing concerning the xlr}ins switch. No explanation of what this is or how it is supposed to work & be wired.
Like most I want a bypass switch, if this can be configured as such I need information, as with these black PCBs w/ ground planes, I can't trace anything out.

 

[Igor]

Since the HE opamp board was not included I guess I'll be sticking a 2520 in there, what are the TBD values for this?

Please check the BOM and documentation. For 2520, use feedback resistors 25K/5k1.

 

[Igor]

Thanks for you reply, Grummy... so it looks like I should have received the op amp board then.
I would sort of figure that, as the op amp would be a big part of what makes this different from all the other LCR eqs...
The pics in the download clearly show the pk/th switch wiring from every angle imaginable, but I find nothing concerning the xlr}ins switch. No explanation of what this is or how it is supposed to work & be wired.
Like most I want a bypass switch, if this can be configured as such I need information, as with these black PCBs w/ ground planes, I can't trace anything out.

You can figure thois out easy from schemo.
For use with xlr/ins/byp option, switch is SPDT ON-OFF-ON toggle.
Center of switch connected to 2.
In mid position, all relays are energized.
When BYP1/2 relays are not energised (/BYP1, /BYP2 points are connected), it is bypass.

Any      support    at  all??????

Hm. All questions you asked is just a matter of some minutes to stare into schematics and meditate

Forum topics actually take a lot of my time, it is like understand what happened, check with the schemo, etc.
If I am busy with my stuff - sorry. I checking the threads couple of times every week, so...
if this is the matter of hardcore troubleshooting, I answer as soon as I can,
the questions like see the bom/schemo are left for when I have a free time.

Example. Let's assume we not boost/cut anything.
Than, signal drop path is r21(22k) to (r22(5k1) in parallel to mid cut (25k)), or mid boost(25k) to r22,
so, we need 25->5.1 feedback resistors coefficients to restore to unity gain.

See the schemos where 2520 used and you find that 25k/5k1 is good point to start with. Etc.

BTW, strange, we included the "original" amp boards with kits.
One of duded told he have not received it or lost when unpacking, so, we resent.
So, if this happened with you too, just drop me an email, will send the He amp board, of course, no charge for this.

 

[nielsk]

Thanks for the reply.
Bear in mind that it makes perfect sense to you because you designed it, and have looked at it probably hundreds of times.
The schematics are on multiple sheets, instead of one complete drawing, so it is a challenge to visualize the complete signal path. The relays are using an unusual  scheme. As this is set up to be used different ways and using non-standard nomenclature, it presents challenges to someone seeing it the 1st time.
I think we can all benefit by keeping this perspective in mind. It's just a simple EQ, but it is presented with so many options that a few simple instructions would go a long way.
I will email about the op amp board.