Chris, send me an email thru the store.

Email sent. Thanks Jeff
Chris


Hi All
I did very well with the 2 vp28 and the Bt50, only that the Bt50 does not work for me as a line signal, I read that something has to be done with the jumpers, but I really do not understand what. Could you explain please, thank you very much

jsteiger

Hi All
I did very well with the 2 vp28 and the Bt50, only that the Bt50 does not work for me as a line signal, I read that something has to be done with the jumpers, but I really do not understand what. Could you explain please, thank you very much
The BT50 is line only. The recommended starting position for the two 3-pin option jumpers is shown in the below pic.
http://capi-gear.com/catalog/images/build/BT50/1_main_PCB/23.jpg

J4 is to select for a typical higher impedance load or a 600Ω load. There is appx 1.3dB more gain when set to 600Z.

Since the input of the BT50 is unbalanced, J5 will increase the BT50's level by 6dB so you can run it from an electronically balanced piece of gear and not loose 6dB.
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.

Hey guys,

I built two BT50's  a few months ago and one works perfectly and the other has a few issues.  I've run tests tones through the BT50 have found that the  12.5k shelf doesn't boost or cut properly. It boosts/cuts starting from about 2k.  The 15k band in peak boost/cuts at 10k instead of 15k and then the 1.5k band actually boost/cuts at 10k.


Any ideas? Thanks!

-Scott
« Last Edit: August 02, 2018, 12:39:29 PM by scotthundley »

RyanCat

Re: [Build] CAPI BT50, 500 Series EQ (a la 550), Official Support Thread
« Reply #84 on: August 07, 2018, 12:13:04 PM »
Hello guys,

i just finished a bt50. I think have a problem in the LF. In peak mod three of the five frequencies seemed to boost/cut not only the chosen frequency but the entire signal. In shelving mod i think everything works fine. I also think that the LPF does not work. In the other bands i have no problems.

Could you please give me some tips where i can look for troubleshooting?!

Thanks!

Jan 

jsteiger

Re: [Build] CAPI BT50, 500 Series EQ (a la 550), Official Support Thread
« Reply #85 on: August 09, 2018, 10:39:53 AM »
Hello guys,

i just finished a bt50. I think have a problem in the LF. In peak mod three of the five frequencies seemed to boost/cut not only the chosen frequency but the entire signal. In shelving mod i think everything works fine. I also think that the LPF does not work. In the other bands i have no problems.

Could you please give me some tips where i can look for troubleshooting?!

Thanks!

Jan
Jan

Measure continuity between the LF Grayhill switch wipers and ground. Its possible that one of them is shorting. You will need to desolder that specific wiper and torque/push/slightly bend it a little to get some space above the PCB and resolder. It seems the width of the wiper pins are varying a little and some have rough edges on the bottom that are making contact to the top ground plane.

The HPF is at 50Hz so it might be hard to hear especially on smaller monitors. The only way to know for sure is to run a sweep or monitor level of a low frequency like 20Hz and compare with the pushbutton in/out.
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.

jsteiger

Re: [Build] CAPI BT50, 500 Series EQ (a la 550), Official Support Thread
« Reply #86 on: August 09, 2018, 10:45:33 AM »
Hey guys,

I built two BT50's  a few months ago and one works perfectly and the other has a few issues.  I've run tests tones through the BT50 have found that the  12.5k shelf doesn't boost or cut properly. It boosts/cuts starting from about 2k.  The 15k band in peak boost/cuts at 10k instead of 15k and then the 1.5k band actually boost/cuts at 10k.


Any ideas? Thanks!

-Scott
Sounds like you have mixed up some of the caps in the HF area.
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.

RyanCat

Re: [Build] CAPI BT50, 500 Series EQ (a la 550), Official Support Thread
« Reply #87 on: August 09, 2018, 11:39:26 AM »
Jan

Measure continuity between the LF Grayhill switch wipers and ground. Its possible that one of them is shorting. You will need to desolder that specific wiper and torque/push/slightly bend it a little to get some space above the PCB and resolder. It seems the width of the wiper pins are varying a little and some have rough edges on the bottom that are making contact to the top ground plane.

The HPF is at 50Hz so it might be hard to hear especially on smaller monitors. The only way to know for sure is to run a sweep or monitor level of a low frequency like 20Hz and compare with the pushbutton in/out.

Thank you very much for your advices. I try to fix it.

I meant LPF not the HPF. This one works as it should.

Jan

jsteiger

Re: [Build] CAPI BT50, 500 Series EQ (a la 550), Official Support Thread
« Reply #88 on: August 09, 2018, 12:00:29 PM »
Thank you very much for your advices. I try to fix it.

I meant LPF not the HPF. This one works as it should.

Jan
Same situation applies. The LPF is @ 15kHz so it may be hard to hear. Its a 2 pole so down appx 12dB an octave which would mean -12dB @ 30kHz. so of course noticeably less than that in the audio band.
Visit the CAPI store at http://www.capi-gear.com

CAPI is not affiliated with, endorsed by, or sponsored by API.