Building with the Soekris dam1121

Config look ok to me for what you want. Connect both pin J2 P1 and P2 to VSS or it will not start.

5K should be ok, if I remember correct I did verify the values.

Thanks for the confirmation. I've already noted the need to connect both J2-1 and J2-2

I'm working on a PCB to connect the Beaglebone Black to the DAM headers; it'll take care of switching PCM & DSD (Beaglebone/Botic outputs them on different header pins) and include isolation and I thought I might as well include the strap resistors.
 
IIR filter selection

@soekris

I know that only few use this capability at all and is not very high priority, but a command to control the IIR filters would be great.

Application would be for me to run a EQ to a speaker system and flat response to a headphone system. At the moment only way to do this I can think of is to update the whole filter file each time I want to switch. Perhaps combining FIR and IIR filter selection so that each filter setting would have their dedicated IIR filter too? Or even a simple on/off command.

-j
 

TNT

Member
Joined 2003
Paid Member
@soekris

I know that only few use this capability at all and is not very high priority, but a command to control the IIR filters would be great.

Application would be for me to run a EQ to a speaker system and flat response to a headphone system. At the moment only way to do this I can think of is to update the whole filter file each time I want to switch. Perhaps combining FIR and IIR filter selection so that each filter setting would have their dedicated IIR filter too? Or even a simple on/off command.

-j

There are actually 4 banks so could choose to make one called Speaker and one Cans. But you cant change name on the banks so you have to be imaginative.

This would be the e.g. "Filter = Linear" option. You have to load your desired filters in these positions of course.

//
 
Last edited:
There are actually 4 banks so could choose to make one called Speaker and one Cans. But you cant change name on the banks so you have to be imaginative.

This would be the e.g. "Filter = Linear" option. You have to load your desired filters in these positions of course.

//

Now that you said this, I rechecked Paul's tutorial to do the IIRs and it seems that I have been an idiot. It is indeed already so that the IIR filters are selected by selecting FIR bank. They are always loaded if present, but only in the confines of that one bank.

Thank you TNT
-j
 

TNT

Member
Joined 2003
Paid Member
Now that you said this, I rechecked Paul's tutorial to do the IIRs and it seems that I have been an idiot. It is indeed already so that the IIR filters are selected by selecting FIR bank. They are always loaded if present, but only in the confines of that one bank.

Thank you TNT
-j

Thanks but as zfe implies, you might have to solve your filtering with FIR. Should be OK, right?

//
 
Ok, so the original assumption is correct. Could/should something be done to it in firmware update? @soekris

Going FIR with EQ is certainly possible and it would be a more powerfull tool, but I feel it to be also a significantly more complicated tool. I have to look into rePhase more, though. IIR biquad calculations are almost trivial in comparison and familiar.

There is also a question of dam horsepower. Some calculation power is already reserved for IIR (I'm assuming this with no actual knowledge) and to fit the actual signal filttering and further signal manipulation in one go might be a tall order for the Spartan with this particular firmware. I have to study this more.

Anyway, a simple command to empower us IIR users would be great. There might be almost dozens of us.
 
Hi

I am planning to use two 1121 in balanced mode and I have some questions.

I use the Mini DSP USB streamer capable of delivering 6- channel i2S and I am using a single channel sub, but I think that using a third 1121 for this sub is going over the hill, so I plan on using another DAC for the sub.
Should I use the Master Clock form the 1121 or from the Mini DSP?
I use Audio lense for room correcting and EQ and is it capable to compensating for any time delay issues between main speakers and sub.

Another thing . I have the Ian FiFo buffer and reclocking with i2S isolator. Will there be any advantage of still using that after the Mini DSP ?
 

TNT

Member
Joined 2003
Paid Member
Hmm... starting up the DAMs (2 boards, balance mode) they don't want to be the either channel. The both play L+R but only when out of phase... bit still not really - it behaves really strange. I'm using this test CD eith L/R channel and phase tests.

I have given what seems to be OK commands - no error messages and "set" shows:

Ch1:

Conspeed = 9600
Volume = -22
Filter = Linear
Mode = Bal-Left

Ch2:

Conspeed = 9600
Volume = -22
Filter = Linear
Mode = Bal-Right

But I get "mono" with what seems to be out of phase signals or is it L-R or something...

Both boards fed the identical toslink signal.

It worked the other week and none what so ever changes made.

What to do? What did I miss?

df / right

00000000 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF ****************
00000010 AA 99 55 66 30 A1 00 07 20 00 31 A1 04 30 31 41 **Uf0*.. .1*.01A
00000020 3D 00 31 61 09 EE 31 C2 04 00 20 93 30 E1 00 CF =.1a.*1*.. *0*.*
00000030 30 C1 00 81 20 00 20 00 20 00 20 00 20 00 20 00 0*.* . . . . . .
00000040 20 00 20 00 20 00 20 00 20 00 20 00 20 00 20 00 . . . . . . . .
00000050 20 00 20 00 20 00 33 81 3C 18 31 81 08 81 34 21 . . .3*<.1*.*4!
00000060 00 00 32 01 00 1F 31 E1 FF FF 33 21 00 05 33 41 ..2...1***3!..3A
00000070 00 04 33 01 01 00 32 61 00 00 32 81 00 00 32 A1 ..3...2a..2*..2*

df / left

00000000 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF ****************
00000010 AA 99 55 66 30 A1 00 07 20 00 31 A1 04 30 31 41 **Uf0*.. .1*.01A
00000020 3D 00 31 61 09 EE 31 C2 04 00 20 93 30 E1 00 CF =.1a.*1*.. *0*.*
00000030 30 C1 00 81 20 00 20 00 20 00 20 00 20 00 20 00 0*.* . . . . . .
00000040 20 00 20 00 20 00 20 00 20 00 20 00 20 00 20 00 . . . . . . . .
00000050 20 00 20 00 20 00 33 81 3C 18 31 81 08 81 34 21 . . .3*<.1*.*4!
00000060 00 00 32 01 00 1F 31 E1 FF FF 33 21 00 05 33 41 ..2...1***3!..3A
00000070 00 04 33 01 01 00 32 61 00 00 32 81 00 00 32 A1 ..3...2a..2*..2*

sat left vol to -20

00000080 00 00 32 C1 00 00 32 E1 00 00 33 A1 1B E2 33 C2 ..2*..2*..3*.*3*
00000090 00 00 00 00 20 00 20 00 30 22 00 00 00 00 30 A1 .... . .0"....0*
000000A0 00 01 50 60 00 03 8A 11 00 00 00 00 00 00 00 00 ..P`..*.........
000000B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000000C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000000D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000000E0 00 00 00 00 00 00 00 00 00 00 00 41 00 00 00 40 ...........A...@
000000F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

//
 
Last edited: