calrec PQ1549 help thread

Then I found the solderbridge near the hifreq pots and the oscillation was gone. Changed back to LM833 on the hifreq board.

Anyone who has any thoughts about different ICs in this great Gyraf project? Sorry about all the posts.
Henrik

gyraf said:

..there currently is a database-problem with exotic characters in posts...

Jakob E.

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Yes but i tried without any exotic characters whatsoever. Anyway, now my answer is there in 10 different posts.  

Can somebody please confirm if these are the ones to change to 22kOhm for unity gain?

Henrik

Bonke said:

Can somebody please confirm if these are the ones to change to 22kOhm for unity gain?

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Yes, change both to 20k for a balanced out config.

Nice!
Thanks alot Harpo!

Henrik

Hi, i am planning to build a stereo diy Mastering, Calrec, since its four bands i guess it can be used pretty well.

For this i need 2 channels in stereo connection, i guess this would be quite easy using instead of 2 gangs potentiometers, 4 gangs(2 for each channel) so adjusting channel 1 will affect channel 2 if channel 2 is linked to channel 1 potentiometers. The same with all switches and other pots.

The problem is i cant find correct 4 gangs of 100k neg log values. Audio maintenance is selling 4 gang 47k and 470k 4 gangs, will these give inaccurate frecuency response and should try finding a 100k 4 gangs neg log pot from another store?

Thank you!

It is VERY hard to find quad-matching pots accurate enough for this purpose.

The only probable route may be switched resistors on a quad deck switch..

Jakob E.

gyraf said:

It is VERY hard to find quad-matching pots accurate enough for this purpose.

The only probable route may be switched resistors on a quad deck switch..

Jakob E.

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Okey, but are there any inexpensive switch(like lorlin rotative) which can give like 4/6 positions with 4 poles? or should i consider using relays?

Thanks jakob!

No, not that I'm aware of - it's one of those things that can't be done on a budget.

Though maybe the uraltone switches mentioned somewhere around here are available in 4x23?

Jakob E.

gyraf said:

No, not that I'm aware of - it's one of those things that can't be done on a budget.

Though maybe the uraltone switches mentioned somewhere around here are available in 4x23?

Jakob E.

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There are indeed:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260693714311&ssPageName=STRK:MEWAX:IT#ht_1449wt_702
Have used two of his 2-poles for output level in my TG-1 built, where they have been working fine for over a year now, but I have no idea what kind of contact materials are used.

They're decent enough (if still the same, made by the same company) - silver-on-bronze.

Jakob E.

Greeat! Thank you jakob and briomusic!

Graph said:

Greeat! Thank you jakob and briomusic!

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I am about to order rotary switches, latching, resistors & PCBs.

10k linear pot, should i use dual 10% 10k linear for stereo? or i will need 1% resistances too in a 2pole?

Thanks for all the help

Where do I find a psu-pcb with bom for a 2ch Calrec?

Any 2x15-18V/100mA powersupply will do fine for the Calreq - make that 200mA for a stereo version.

gyraf said:

Any 2x15-18V/100mA powersupply will do fine for the Calreq - make that 200mA for a stereo version.

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Thanks!
I have many questions, and don't feel I understand enough yet. Please see:
http://www.groupdiy.com/index.php?topic=46750.msg586962#msg586962
What would be a typical choice? (Farnell)

Edit: I guess I'll go for an JLM AC/DC Ver. 4 kit

I'm planning my complete part-list. One thing I don't understand:
Looking at the front-panels here: http://www.groupdiy.com/index.php?topic=756.msg10112#msg10112
It seems like the Calrec has four bands
I intended to by a case from Purusha http://www.diy-racked.com/diy-talk/viewtopic.php?f=7&t=18
But his cases are five-band.
What's the correct bom/ pcb / case combination?

Is this the right pot for the Calrec eq?
http://www.audiomaintenance.com/acatalog/om-01-072_extended_info.html

Another question:
I see Purusha is selling cases for a 2ch Calrec with 5 bands. What pcbs and bom is for that one?
Edit, found this : http://www.groupdiy.com/index.php?topic=27972.0

A feature question:
Does the Calrec have HPF? Or is the lower band shelving/peak?
Is there a list of Q and band-types somewhere?

Thanks!

Another question:
I see Purusha is selling cases for a 2ch Calrec with 5 bands. What pcbs and bom is for that one?
Edit, found this : http://www.groupdiy.com/index.php?topic=27972.0

Click to expand...

that's the sontec case, not calrec