e-licktronic Forum

EchoBoy

+1 for Flam. It is an important feature of the 909. I posted the timings of a TR-909 for each flam value here: http://www.e-licktronic.com/forum/viewtopic.php?f=25&t=1430&p=8983&hilit=flam#p8981 The jitter on the waveforms is due to the internal sequencer of the 909, which has a jitter o...

EchoBoy

There are SN74LV4051A or CD74HC4051 and DG9051 even.. These won't work. The outputs must be held when not selected by the (A,B,C,INH) bus, resp. (MUX_A,MUX_B,MUX_C,INH_MUX1/2) in the sequencer schematic. The issue is the leakage which is too high to keep the value long enough. So either a daughter ...

EchoBoy

The CD4051 demultiplexors could be replaced by Analog Device SMP18FPZ but they are end of life and sold at 17€ each on mouser. Another option could be to replace the CD4051 by daughter boards adding sample and hold circuits on the 8 outputs of the CD4051 but that requires to design and build mini-pc...

EchoBoy

It is actually not an issue specific to my nava but likely an issue of the software (and/or hardware).

For futher information, I posted my observations on this issue in this thread: viewtopic.php?f=25&t=1425

EchoBoy

The Flam function is a must have feature. I thought it could be helpful to get the timings of the TR909 for flam modes 9 to 16. The timing of the flam is not affected by the tempo. The waveforms below show the TRIG signal when flam is enabled - the first pulse is the initial trigger - a few ms later...

EchoBoy

Getting closer to the schematics, I notice a major difference between the TR909 and the Nava... Vincent, please correct me if I am wrong. In the original TR909 design, the sequencer drives 4174 6-bit D-latch registers, which are used as DAC with series of resistors. The 6-bit value issued of each 41...

EchoBoy

Hi Vincent, Issue with level of ACCENT_BD signal with vs. without accent (not total accent): - TR909: the amplitude of the ENV2 without accent is half of the amplitude of the ENV2 with accent - Nava: the amplitude of the ENV2 without accent is 2/3 of the amplitude of the ENV2 with accent Would it be...

EchoBoy

Here is a comparison between a TR909 (in red) and the Nava (in blue) with a pattern alternating with accent and without accent, played quickly: ENV2 : https://preview.ibb.co/fUdcKa/Bass_Drum_Env2.png This graph has been taken in AC mode. In DC mode the oscilloscope shows the same ratios without acce...

EchoBoy

I am currently tuning my Nava and noticed surprising peak voltages of the ENV2 of the Bassdrum. I would have expected that without accent, the peak voltage would have been half of with accent. It is not: at R41, I observe 9V without accent, 12V with accent on my Nava With the same probe, same oscill...

EchoBoy

@deejayraoul: Did you keep the external supply option to make a SNR comparison between external and internal supply? I did not have time to investigate on my hum issue yet. Sorry Jeroenbvo for not having replied earlier. In my case the hum is present on all outputs, whether instruments are played or...

Search found 29 matches

Re: How to use Flam in Nava?

Re: Accent level in 1.023

Re: Accent level in 1.023

Re: Bassdrum ENV2 peak voltages

Flam timings

Re: Accent level in 1.023

Accent level in 1.023

Re: Bassdrum ENV2 peak voltages

Bassdrum ENV2 peak voltages

Re: Internal power supply and PSU mod