seppoman

I´d say 95% are - I never saw soldered SIDs personally. But if you´re fast, try this one: http://www.midibox.org/forum/index.php?topic=8280.0 12 Euros is a good price and postage will probably be reasonable. Seppoman

The PIC thing has nothing to do with the SID sound. Maybe it´ll bring some interesting sounds, but don´t wait for a reproduction of the character of the SID... About shipping costs: Of course things like whole synths that are big and heavy will cost a fortune for international shipping. But I once won an auction of a package with C64s and loads of old joysticks disk drives etc. and I persuaded the seller that he´d just pull out the SIDs and throw the rest into the garbage. So if you get in contact with sellers before bidding, this might be a way to get reasonable shipping costs. Seppoman

no. The SID was constructed for the C64 and built by MOS who later were even owned by Commodore. As far as I know, no other machine used them. If there are no C64s in the Ukraine, then eBay is your friend. eBay Germany alone has a few hundred C64s sold every week, you just need to find a seller that ships to your country. Seppoman

the Spectrum is much more old-skool than a Soundblaster. A quick search on google reveals that the first spectrums had no dedicated sound chip at all, the later ones had an "AY-3-8912", which has nothing to do with FM synthesis. So just search the Wiki for the list of SBs which are known to have the OPL3 on them. These old cards are really cheap and easy to get. Seppoman

Hi all, and now for something completely different :) My girlfriend´s company sends a Christmas (Flash) game to their customers every year and they needed some music for it. here´s the results: http://www.seppoman.de/stuff/DeckTheHalls.mp3 http://www.seppoman.de/stuff/Wonderland.mp3 Both songs are SID-only. I´ll probably do a longer version of Wonderland which also has the bridge, but this year´s game needed only 20 seconds of music... BTW and totally music-unrelated: A recent finding at a store - perhaps a possibility for people who can´t afford a real MidiBox, it´s only 20 Euros ;) Merry Christmas to all of you :) Seppoman

Gratuliere :) und woran lags? Seppoman

Hi, honestly, if you don´t even have the time to read a bit over uCApps to find out what is needed, I seriously doubt that you´ll have the time to build the synth ;) About costs: If you want it easy, then buy kits for all necessary boards from SmashTVs shop. All kits, 15 encoders and a bag of LEDs is around 250 USD from him. You can save some bucks if you buy the parts elsewhere, but Smash´s price is fair considered you won´t have to take care of everything yourself. Then you´ll need some buttons, audio/midi jacks, a LCD etc., which is perhaps another 50 bucks. The most expensive thing is the front panel. I don´t know the exact amount with FPEs current prices, but it will be around 150-200 USD. And you need 4 C64s for the SIDs, a case and PSU. I´ve got mine quite cheap for around 15/piece, but this depends on where you live and how the prices are in your country. This totals to an amount of around 550-600 USD for the full version. Seppoman

hmmm, misst Du die 5V und 12V Versorgungsspannung überall korrekt (laut Step-by-Step-Anleitung)? Ferndiagnosen sind immer schwierig. Was evtl. helfen würde, sind (einigermaßen hochauflösende und scharfe) Fotos der Platinen (von oben und unten). Viele Grüße, Seppoman

Kann es sein, daß Du den Link-Button nicht aktiviert hast, oder Midi-Kanalnummern falsch eingestellt sind? Das ist mir mal passiert, einen ganzen Abend panisch Fehler gesucht - auf Kanal 2 gesendet - dann Kopf kräftig gegen die Wand geschlagen ;) Seppoman

Hi, whether 500mA is enough depends on your implementation. With only one SID, a 2x20 LCD and not the full control surface, 500mA is plenty. One of the most power consuming parts is often the LCD backlight. I´ve got a 2x40 LCD whose backlight takes up to 400mA if you adjust it to max. I used a 15V wall wart with 800mA capability and adjusted the backlight to around half power. My box runs with this cirquit: http://www.ucapps.de/mbhp/mbhp_core_power_fix.pdf With the additional 7809, the dissipated heat is split to two regulators. The core regulator got a normal heatsink, while the 7809 is mounted to the (metal) case. I find the temperature of the regulators quite acceptable. Why are people recommending the C64 PSU all the time? There are two reasons: 1. Using it keeps the heat out of the box as regulation of the 5V power is already done in the PSU. 2. Supposedly, the noise floor is better using the ...optimized design. I tried both, and couldn´t really hear a significant difference. At first I had a problem with ground loops (hum), but avoiding these and taking care for clean wiring in the box got me a comparable noise floor. Probably there´s some measurable difference, but background hiss is really a smaller problem compared to all the dirt coming from the 6581. Anyway, aren´t these imperfections part of what we all love about this old bastard? Seppoman

Hi, Actually I don´t know if it´s necessary to have different versions for different platforms? Eagle3d is a ULP script running from inside Eagle, and ULP is an interpreted script language just like Perl, so it will probably run with Eagle on all available platforms. Only the installer is Win, so you will have to copy the files to the right directories yourself. Seppoman

Hi Michael, I´m sorry, but this is not correct. Hex gets counted from 0 to 15 - as the name implies, because the full name is "hexadecimal" which means 16. From 0 to 7 would be the octal system which is not used in programming (or nearly anywhere else ;) ). About hex to decimal conversion: Just as decimal e.g. 25 means 2*10 + 5*1, hex 0x10 means 1*16 + 0*1. The digits from right to left in all systems mean (number * (base to the power of the digit )) - the digit is counted from 0. So with hex it is digit: ... 3 2 1 0 power : ... 16^3 16^2 16^1 16^0 equals: ... 4096 255 16 1 so e.g. a 4 digit hex value of 0x3A20 means (3*4096 + 10*255 (A hex=10 dec) + 2*16 + 0*1) = 14870 :) The reason why hex is often used in programming is that it converts quite nicely to binary. Each binary "Nibble", that is 4 bit, is represented by one hex digit, that´s because 4 digits binary also represent numbers from 0 to 15. So you can calculate the binary value of large hex numbers in your head and don´t have to use a calculator all the time. Greetings from Nerd-Land :) Seppoman

Hi, I haven´t heard or seen anything from him in real world, but his stuff looks nice: http://www.elby-designs.com/ e.g. the ASM-2 is a relatively simple analog synthesizer that can either be built as a modular or a hard-wired version. The Pixie also looks nice, but is more expensive. Seppoman

Kannst Du nicht mal konkretere Fragen stellen, bzw. z.B. auch mal genauer beschreiben, was Du gemacht hast, und was genau Du schon probierst hast. Fotos von Platinen incl. Verkablung sind z.B. fürs Forum immer hilfreich beim Fehler suchen. Deine Fragen sind momentan eher in Richtung "Ich hab hier ein Auto, sagt mir endlich, warum das nicht fährt!". Wenn Du nicht verrätst, ob Du Sprit drinhast und den Schlüssel im Zündschloß, kann man nicht wirklich anfangen, Ratschläge zu geben. Außerdem (sorry wenn ich jetzt etwas persönlich werde, aber es tut echt manchmal weh!) schadet es auch nicht, das eigene Hirn zu benutzen und auch, Ratschläge anzunehmen. Z.b. haben Dir inkl. mir mindestens 3 Leute unabhängig gesagt, daß logarithmische Potis ungeeignet sind. Viel Spaß beim Experimentieren, es wird aber einfach nicht zufriedenstellend funktionieren! Tipps bzgl. mal ein Buch über Elektronik-Grundlagen lesen kamen auch schon. Das wäre echt wichtig!!! "Definitiv NICHT" bezog sich auf die Richtung der ICs. Wenn Du Dir die Darstellung der ICs im Schaltplan und auf dem Bild der Platine mal anguckst, wirst Du feststellen, daß die Beinchen alle unterschiedliche Bezeichnungen haben. Die werden also sicher nicht alle austauschbare Funktionen haben, oder? Außerdem ist an einem Ende immer eine Markierung (Kerbe oder Punkt). Diese hilft, zu erkennen, wo welche Beinchen an dem Chip sind. Seppoman

Hi, 8.5 and 14 V is perfect. If you go that way, just take the cheaper variant, it still is way stronger than necessary. Seppoman

Hi, looks nice. What are the voltages of S1..S3? If you want a ready to use PSU, take a look at pollin.de - they have a +5/+12/-12V regulated PSU with mini-DIN connector (like PS/2) for only 3.95 Euros: http://www.pollin.de/shop/shop.php?cf=detail.php&pg=OA==&a=MDU0OTQ2OTk=&w=Njk1OTc5&ts=0 They ship internationally - don´t know the postage though... Seppoman

Hi Thorsten, why´s that? Is there something about the SSOP package that is announced to be discontinued or did you confuse "16-Lead package" with leaded? The part is available RoHS conform. Hmm, I´ll continue to search, but I think I´ve seen most of the established companies parts now, and the DAC probably shouldn´t be too exotic. Another idea: Coming back to the shift register idea - what about using a single parallel DAC in combination with 8 S&H ICs. The LF398 looks nice and is around 2 Euro. And there are parallel versions of the 7614. The 7624 is quad (but also with loaddac# line etc), but there´s the 7613 single dac. With only one dac you could probably keep the C/S, LOADDAC and R/W at a fixed state (as the 595s are latched at once anyway) and just set the s/h control alternating. Only problem is that the 7613 is also only available as SSOP package. Seppoman

Hi, another day of searching - Maxim doesn´t offer anything at a realistic price. Analog Devices are either expensive, too, or they come in extremely small packages. I also searched for parallel DACs but most have only one or two channels and are more expensive than the serial versions anyway. And with shift registers, few channels per chip mean a lot of shift registers (if there are dedicated data lines for every DAC) or an awful lot of bridges on the board. I´d say with the 80x100 mm restriction it would be even hard to get 4 channels onto one board. One of the goals of a redesign should be simplicity, and that is contradicted by the shift register concept. About the DAC7614/15: I think it has the best value/price ratio. The specs are really good. The only real disadvantage is that it has no cascading output, i.e. probably we´d have to use two outputs of a 74hc595 to control the CS and LOADDAC lines. If using this DAC, perhaps it would be a good idea to put only 4 channels (one DAC) onto one AOUT board. This way people needing only few channels for filter control could save half the money and effort. Thorsten, could you please comment on the DAC7614/15 and the LTC2620? Seppoman

Hi, just wanted to add new findings :) : There´s another 8 channel 12 Bit SPI DAC I´ve found: The Linear Technology LTC 2620. It has INL specced 0.75 typical and 4 max. It is available from RS components for around 18 Euros. Of course the INL is not as good as the DAC7614, but it´s 8 channels, has less unnecessary control pins and at least the specs are noticeably better than the TLV dac. I don´t know how probable it is that the INL goes higher than the typical value and under which circumstances this can happen? Is it just that rarely you can have bad luck and get a bad one or does the value rise e.g. with temperature or age? Another problem is the SSOP16 package (Pin spacing is 0.65 mm). I would be able to solder it but it´s even less newbie friendly than SOIC. So all in all I´m not too enthusiastic about it... BTW, there is also a DAC7615 version that is double buffered (otherwise same specs like 7614). I don´t know if this is necessary or useful and I haven´t found it under around 20 Euros. regards, Seppoman

Hi Thorsten, yes, I also noticed that this afternoon, and it gave me a bit of a headache. Actually, if my calculator doesn´t lie, +/-6 LSB is around 15 mV? if full scale is 10.67 V (1V/Oct) then 2 LSB is 5.2 mV and 6 LSB would be 15.6 mV. 1 Semitone is 83.4 mV, so 2 LSB is already more than 6 cents detune and 6 LSB is inacceptable!! Still an error of 6 LSB is even better than an 8 bit DAC... I wasn´t aware that CV is so receptible to tuning errors and you can´t get a single clean interval off an 8 bit CV system. Even though the curve in the datasheet shows "only" INL of around +2/-1 LSB I´d still say this DAC would be noticeably inferior to the max525. But TI has some other nice DACs. Sadly there are no better 8 output DACs in usable packages, but there´s the DAC7614UB (TI/BurrBrown) with a max nonlinearity of 1 LSB. The curves in the datasheet show that it´s typically around +/- 0.25 LSB! It needs an external reference but should be quite simple otherwise. It is 12.60 Euro at farnell for SOIC. There´s also a PDIP version but the equivalent PB type would cost 25 Euros, so I´d go for SOIC anyway. It´s also available from Mouser. What do you think? Seppoman

Hi, I´ve been searching for nice DACs in the last time. A very cool IC is the TLV5630 from Texas Instruments. It is a 12 bit, 8 output converter with internal reference (no MAX6007 anymore) and a cascadable SPI interface. Only drawback in comparison to the max525 is that it doesn´t have a gate logic output. But this could be either solved via the normal DOUT chain or a dedicated 74hc595 integrated to the AOUT board. It is available from e.g. Farnell for 15.49 Euros including VAT (1-9 pieces). If the real El Cheapos want to save even more, there are also pin- and instruction-compatible 10 bit (TLV5631) and 8-bit (TLV5632) versions available. And TI´s free sample program is is also really world class compared to Microchip/Maxim etc. This IC is only available in SOIC form factor, but I think people building an AOUT are more ambituous than average anyway and the OPL3 board has already shown to a number of MidiBoxers that there´s nothing to be afraid of SOIC SMDs as long as you have a premade PCB. And for 8 (!) AOUT_LC DAC channels you´d need to solder hundreds of resistors, so one SOIC is definitely the better choice. Honestly, I don´t have much experience in DAC design up to now and I don´t have any CV gear around to do real world testing. But I´m in an extensive layouting phase anyway so Thorsten, if you have a look over the data sheet to confirm that this DAC is suitable and major changes in the OpAmp part of the AOUT won´t be necessary, I could do a board. I´ve got TLV5630s lying around here and also have the opportunity to etch boards at university, so after a few questions are settled I could send you a free completed board for testing and programming :) Seppoman

Hi all, I´m searching for a SMALL Hitachi-compatible 2x40 LCD. After searching quite a lot of manufacturers, it seems that there is some kind of standard size with a viewing area of 154x16 mm. The application will be over some stop switches of a church organ console and these switches are only about 2.4 cm wide. If I put 4 switches beneath a standard display to have 2x9 characters for each, they´d have to be mounted with ugly gaps inbetween. So to avoid these gaps, a 2x40 display with around 100 mm display area width would be necessary. Does anyone have a hint for where to find such a display? My second option (with higher programming effort) I came up with is to use a graphic LCD or VFD with matching dimensions and built-in character generator. I´ve found two acceptable VFDs from Noritake. One is 280x16 dots on 137mm, the other 254x32 on 115mm. But with the 280 VfD, I´d get only 2x8 characters for 5 switches and 7mm of unused pixels on each side, and the 254 would mean 4x8 quite small characters for 5 switches with the characters ending 3mm before the switch on each side. Both solutions are not really optimal. So another interesting hint would be a graphic LCD with e.g. 256 x max 32 pixels and a display area of around 120 or 100 mm. All graphic LCDs with high horizontal resolution I found so far have at least 64 pixels vertical. As you might have guessed by now, the project has nothing to do with MIOS. It´s about a real church organ and the console will get around 30 user-assignable stop switches, so there will be a dedicated AVR controller driving around 6 to 8 displays ;D Anyway, the possible answers would probably be of interest for MidiBoxers as well, so I´m asking it here :) Any thoughts or hints are appreciated :) Seppoman

Hi Stryd, if you´re looking for DIY-projects, have you already heard of http://www.gyraf.dk? (go to "DIY Projects"). He is the man behind the very popular Urei 1176 clone and has quite a few nice comp, eq, micpre projects. As a mastering compressor, I´d go for the SSL MixBus clone: It´s a clone of the main compressor of the SSL 4000 Series mixing desks. We have one of these desks in my university´s (now second-best) studio, and it sounds absolutely fabulous :) The 4000 clone is a quite simple design. The only special part about it is the THAT2180 VCA. Everything else is cheap standard parts. There´s a PCB set available for 13 Euros, so if you build the case/panel yourself, the rest is around 100 Euros. I have been wanting to build one of these for years now, and also an 1176 clone. The 1176 is also really cool, but adds too much character to be useful for mastering. But I´m getting distracted by all these nice MidiBox projects everytime I´d want to start one of these ::) Seppoman

das hat mit Genauigkeit rein gar nichts zu tun. Logarithmisch macht nur für analoge Audiosignale Sinn, weil eben die Widerstandsänderung ca. dem Lautstärkeempfinden des Menschen entspricht, d.h. wenn Du den Poti von Voll auf Halb drehst, wirkt die Musik halb so laut. Wenn Du aber eine Audiosoftware steuerst, kümmert die sich selbst um diese logarithmische Skalierung. Ein log. Poti an einer MidiBox bewirkt, daß du in der Mittelstellung nicht 64, sondern irgendwas unter 50 als Ausgangswert bekommst. Nachdem wie gesagt die Software sich selbst um den Logarithmus kümmert, hast Du damit bei halber Einstellung eher ein Drittel der Lautstärke. Bei Filtereinstellungen oder sonstigen Parametern bedeutet das, daß die gleiche Änderung des Werts im unteren Bereich eine wesentlich größere Bewegung erfordert als im oberen. Das ist genau der Grund, warum alle lineare Potis verwenden und auch überall auf uCapps lineare Potis/Fader gefordert sind. Mit logarithmischen gehts grundsätzlich (solange sie einigermaßen um die 10 kOhm haben - ein analoger Mixer hat sicher verschiedene Werte eingebaut), Spaß hast Du damit aber nicht. Ich würde wirklich empfehlen, dir dafür neue Potis zu kaufen. Gerade für DJ-Zwecke sind ja nicht soooo schrecklich viele nötig. Im Vergleich zu den Potis aus einem abgeranzten Billigmixer bist Du auch qualitativ mit 1Euro/Stück schon besser, und wirklich gute gibts um die 2-3 Euro/Stück. Seppoman

7,5V reichen, ist sogar besser. 9-10 V (Spannung, nicht Leistung, wenn ich mal kurz klugscheissern darf ;) ) bezweifle ich allerdings. Unter Last liefern solche Netzteile schon einigermaßen genau die eingestellte Spannung. Seppoman P.S. man kanns nicht oft genug sagen: VORSICHT mit Netzspannung!!! Alle Übergänge/Leitungen, die 230V führen, müssen so isoliert werden, daß die Drähte nicht berührt werden können und sie auch nicht abgehen können! Isolierband ist Pflicht, besser sind größere Mengen Heißkleber an allen wichtigen Stellen.