Mini digital reverb?

[audiomaster]

reverb technical help

can any one sugest me the equv./replacement for AL1101(adc)& AL1201(DAC)
THNKS

[puretube]

http://www.diystompboxes.com/smfforu...?topic=49130.0

[Steve Conner]

Yes, I have an electronic background. I'm actually an EE and currently designing computer-controlled lab instruments for a living. I have built and programmed DSP systems from scratch, and could make a digital reverb entirely out of Game Boy guts if I wanted to. But what's the point when I can buy a ready-made circuit board for a good price.

FWIW, the board I bought uses some Crystal Semi codec chip in place of the AL1101 and AL2101, I forgot the part number.

I haven't installed it yet as I was too busy partying over Christmas and New Year and the amp is now on loan to a friend who's using it for tracking in the studio.

[puretube]

AL3201 & CS4271... driven by a 8.192 quartz
plus: 2115 & a tiny ball-grid-array chippy I can`t decipher... (eprom?/µP?).

[audiomaster]

Sorry sir i dont want to heart you, I am new to DSP and want to develop programs. I have 3201 and like to complete. I dont have alesis made adc/dac. I understand that they are left justified. I'm searching substitutes. Can you help me any way?

Regarding DSP programing, is there any scope for designing DSP modelling
amplifier? any readymade board available?
regds.

[audiomaster]

AL3201 & CS4271... driven by a 8.192 quartz
plus: 2115 & a tiny ball-grid-array chippy I can`t decipher... (eprom?/µP?).

CS4220 WILL DO THE SAME THING?

[Steve Conner]

I think the tiny chippy is a uC that replaces the Alesis factory programs with 16 new ones, and maybe programs the config registers on the codec chip too.

Audiomaster, the problem with finding substitutes for those converter chips is that they only have wordclock inputs, and use an onboard PLL to regenerate the master clock that all sigma-delta converters need. If you make up your own master clock divider, or choose an ADC that has one, you can probably use just about any converter chips. Or 50% of them... I believe they fall into two categories, I2S and JIS, aka left and right justified, but there are other differences in the clock signals too.

Again though, that's another reason why I bought a ready made board! The last time I did this (at work) it took me a good few weeks of 9 till 5 work and >20 pages of lab notes to choose suitable ADCs and DACs, read all the datasheets together, figure out how to interface them to my DSP, and get all the config registers programmed, everything debugged and working, and the analog side free of noise. If you managed to get a 3201, can't you get the matching converters from the same place? It would make your life a lot easier.

For a DSP modelling amplifier, probably the best thing would be one of the Analog Devices SHARC evaluation boards. But the software that comes with them is crippled to 30 days, and then costs about $10k to buy. And you wonder why there aren't any hobbyist DSP modelling amps.

[audiomaster]

[QUOTE=Steve Conner;10802]I think the tiny chippy is a uC that replaces the Alesis factory programs with 16 new ones, and maybe programs the config registers on the codec chip too.

Audiomaster, the problem with finding substitutes for those converter chips is that they only have wordclock inputs, and use an onboard PLL to regenerate the master clock that all sigma-delta converters need. If you make up your own master clock divider, or choose an ADC that has one, you can probably use just about any converter chips. Or 50% of them... I believe they fall into two categories, I2S and JIS, aka left and right justified, but there are other differences in the clock signals too.

Again though, that's another reason why I bought a ready made board! The last time I did this (at work) it took me a good few weeks of 9 till 5 work and >20 pages of lab notes to choose suitable ADCs and DACs, read all the datasheets together, figure out how to interface them to my DSP, and get all the config registers programmed, everything debugged and working, and the analog side free of noise. If you managed to get a 3201, can't you get the matching converters from the same place? It would make your life a lot easier.

For a DSP modelling amplifier, probably the best thing would be one of the Analog Devices SHARC evaluation boards. But the software that comes with them is crippled to 30 days, and then costs about $10k to buy. And you wonder why there aren't any hobbyist DSP modelling amps. :

QUOTE: I'VE MANAGED TO GETA FEW 3201 FROM 'BDNC' BD3201 (NOT ALESIS MADE) AND THEY DO NOT PRODUCE ADC & DAC. THEY RECOMEND ME USE CS4345 & CS5344 (24BIT LEFT JUSTIFIED) BUT THRY ARE NOT AVAILANLE LOCALY.

FOR MODELING AMPLIFIER 'FENDER' IS USING TMS320VC5402 (FIXED PT. DSP) WITH CODEC TLC320AD77C. BOTH ARE TEXUS MADE. RIGHT NOW THESE ARE BYOND OF MY KNOWLEDGE.

ANOTHER THING, I WAN TO USE AN ENCODER (QUADRATURE OR A/B CODE) TO SELECT 16 PROGRAMS (WHAT 3201 OFFERS), WITH A PAIR OF 7 SEGMENT DISPLAY INDICATION. THE PROBLEM IS TO ENTERFACING WITH A 8051 CORE uP. DO YOU HAVE A IDEA HOW TO INTEFACE AVOIDING BOUNCING & CHATTERING.

[puretube]

4220? does it for B********

[Steve Conner]

Wow, I didn't realise the Chinese had managed to rip off the AL3201 Whereabouts are you? It can be pretty hard to get hold of specialised ICs in some countries, sure enough.

Yes, I do know how to do that thing with the quadrature encoder. There are lots of ways to do it, but a simple state machine with a 16-entry lookup table always worked for me. Debouncing is just a case of waiting for things to settle before checking them. The best way to do it often depends on the particular uC you're using, and I don't use the 8051, so I'll keep quiet.

[audiomaster]

[QUOTE=Steve Conner;10816]Wow, I didn't realise the Chinese had managed to rip off the AL3201 Whereabouts are you? It can be pretty hard to get hold of specialised ICs in some countries, sure enough.

Yes, I do know how to do that thing with the quadrature encoder. There are lots of ways to do it, but a simple state machine with a 16-entry lookup table always worked for me. Debouncing is just a case of waiting for things to settle before checking them. The best way to do it often depends on the particular uC you're using, and I don't use the 8051, so I'll keep quiet.

pl. visit www.bdnc.com for rip of al3201.

for encoder please explain a little bit.

[audiomaster]

3201

[quote=Steve Conner;10816]Wow, I didn't realise the Chinese had managed to rip off the AL3201 Whereabouts are you? It can be pretty hard to get hold of specialised ICs in some countries, sure enough.

Yes, I do know how to do that thing with the quadrature encoder. There are lots of ways to do it, but a simple state machine with a 16-entry lookup table always worked for me. Debouncing is just a case of waiting for things to settle before checking them. The best way to do it often depends on the particular uC you're using, and I don't use the 8051, so I'll keep quiet.

pl. visit www.bdnc.com for rip of al3201.

for encoder please explain a little bit.

[Steve Conner]

Well, I finally got this thing working, for a while at least! I got a nominal 12V (actually nearer 10-11V) from the heater winding using a full-wave doubler circuit. Since the winding was centre tapped to ground, I ended up using a strange doubler circuit with 3 capacitors and 4 diodes. I also use the 12V rail to power the channel switching relays and some LEDs.

I soldered a small daughterboard to the RA-FX3C that held a 5V regulator, some coupling and bypassing caps, and some jumpers to select the effect. I couldn't find a convenient place on the amp chassis for a rotary switch, so I figured I would just find my favourite one and leave it there.

The RA-FX3C datasheet shows the input being driven by an op-amp: I used a 12AX7 cathode follower instead, since I had already wired that up. I basically spliced the board into the existing parallel FX loop that I had put in the amp a while back.

All of this worked great on the bench. I wedged it on the "Spring Reverb" patch and it sounded pretty decent. But when I put the amp back in its cabinet and tried it again this morning, no reverb I'm hoping it's just a loose connection, and not the tubes rejecting the solid-state transplant

[Steve Conner]

It was just a loose connection, all working now

[audiomaster]

Ra-fx3c

Hi Steve, nice work. But do you tried for the PGM-5 (one variable parameter)?
What codec they use with the 3201 core DSP? What are the part no U4 & U5?