Diy audio attenuator. The power amp input impedance is 47K.

Diy audio attenuator All done with some clever use of digital logic and accurate timing. level for my camcorder. It was never installed and is brand NEW! These sell for $207. 00 Includes Shipping to lower 48 USA I just want to conform from other members here that does Lpad attenuator affect sonic quality of tweeter. DIY XLR Attenuator Specs Help. Need to have 1 db step attenuation for balanced line level signal 0 to -12db attenuation would be great. Can you help me compute for the resistor values? It has 22 steps. I love hiding audio gear in unassuming, rustic boxes. I have R1 to R10 in pairs to set the series attenuator to 4k I have the next group R11 to R16 to set the shunt attenuator to 20k. C. What are the pros and cons of 64 steps attenuator with 10k and 27k constant input resistance, DIY Volume Control (Relay Attenuator) diyAudio Community diyAudio For an input attenuator you already know the maximum input voltage and the resistance of the attenuator. Have I got it right? This is the stepped attenuator solution I wanted to use, variable steps of resistors that shorts input to ground. It is of early more sturdy production. 01% Input Sensitivity: 500mV Input Impedence: 20Kohm Crosstalk: -100db i need a sound attenuator which will just control the sound without distorting any idea where i can look these. Thank-you, Russell WIlliams . Brand new ones cost $10 each from Mini Circuits, model # HAT-20+ They are good to 2 GHz. XLR pin 1 is not an "audio signal ground". AT2380 DIY stepped attenuators news. 1 micro control unit is used to control everything, I have been playing about with this for a couple years trying to develop a really good intuitive user interface. at 20hz down . My questions are: 1. At 3/4 volume, shorting the resistors in and out, I could easily hear the highs were attenuated with 100K vs. I have my unbalanced design worked out using a PGA2310, but haven't seen much discussion of designs/chips for balanced (differential) lines. . I want do do a shunt stepped attenuator 10K with 23 steps, the question: is this table showing the right values? Step 1, Attenuation = Infinity dB, Rx = 10000 ohms, Ry = 0 ohms. The attenuator steps may not be the same as unloaded, but that's of little consequence. Hence, buffered before AND after the attenuator. I suggest 12-mil for signal traces and 20 mil for relays if possible. I have seen some on the internet, but they are expensive. The reason is for quiet home playing, but still with the tone , features and speakers of a full Not sure about that but here goes: What you need is a high quality rotary switch such as Elma 23 positions, make before break. The DAC has digital attenuator which has to be set to ~-40db for comfortable listening volume. Using a 10Kohm attenuator with a 15Kohm power amp will probably work and sound just fine. the TVCs will cost equal to the whole of the rest of the project. But I don't think that usual stereo potentiometer can work correctly, because they are kOhms impedance (20100 or more). Does this mean each winding is 8ohm? Does this mean each winding is 8ohm? When using various online L-Pad calculators, a 3dB attenuation requires 2. Except this I got tired of cobbling together resistors to attenuate amplifier signals when doing distortion measurements. I need to decide on a final attenuator configuration before i can order the front and rear panels for the finished chassis. It will allow me to push preamps to high gain level and see if t DIY For pads that operate at line level, you can just build it onto a piece of Vectorboard or use a terminal strip or terminal board. lightspeedattenuator. html (in my case, 47000ohm for each, and The result is a design for a bypassable resistive attenuator that can work at 4 or 8 ohms and features treble compensation. So I Hello forum, I have decided that it is a moral imperative that I build a XL-10 circuit to perform the 'null' test and adjust the Excelinear trimmer capacitor in my XL-280(s). So, in the spirit of DIY, I encourage everyone who can contribute, to share information about digital attenuation, no matter how small. Joined 2003. Search titles only By: Search Advanced search Although I, personally, have not used LDRs for an audio attenuator, the LED/LDR optoisolators ARE, apparently, a "known good way" to implement such an attenuator, and have been used that way for at least 20 years, even in some high-end commercial audio products. Overall performance is good except when it's set to -0. Choose the P = V^2 / R version and insert your numbers. I used the SMA versions at work, and there were no issues with any of them unless someone screwed one of them into a 5 watt radio and transmitted through them. 5k ohm (I've seen some optocouplers that supposedly go to 60 In principle they have as much effect as the other fixed resistor because the two together are simply a series pair forming an attenuator. It is a thingy (either kit or complete box with input and output sockets) that has a ladder-type digitally controlled attenuator. Hello, I want to build an attenuator using a couple Intact Audio Autoformers and control the attenuation level from an Arduino device over I²C. Tried connecting attenuator ground to case. All the parts are easy to find, and for a few hours’ work Hi I use a DAC connected directly to a power amp to drive my speakers. Vendors Audio Poutine Holton Precision Audio Elekit XRK source. Go too low and you place too much of a load on the preamp. Won't the ladder type just add more complication to the build? ••• Speaker Attenuator DIY. Its IR remote control provides convenience over solutions with stepped attenuator rotary switches. For low-level measurements, having a rats nest of parts and wires on the bench was bad from a noise standpoint as well. The easiest enclosure for I recently constructed an LDR attenuator and volume control from Tortuga Audio. Anyone know the best way to stop popping noises when turning up volume? I recently installed this in my linestage: Balance XLR 23 Stepped Attenuator Potentiometer 50K Log | eBay However the "thud" each time I turn up the volume is rather annoying - there is no dc offset at the source. random-science-tools. I am really happy with the Clone Note and am glad I made the purchase. use a 10k in line and then choose a grounding resistor from the list. Joined 2004. In practice, and at higher levels of attenuation as the switched shunt value becomes lower and lower then any of its 'problem contributions become less. This method employs extra resistors to dissipate electrical energy as heat. For stereo, I would need two of them. Can you guys recommend a way to do this? Stepped 2 ch. (Speakers are 2 So far all I have managed to do is get the pga2310 to run in a loop increasing the volume up and down. I have just had a conversation with a friend about Gainclones, DIY audio etc. Hi guys, I don't suppose someone could help me out with the wiring on the stepped attenuator I'm building? I've attached a photo of the unit, and the resistor values i bought are for a series attenuator, whereas most of the guides online seem to be for the shunt type. Last edited: 2012-08-13 8:20 pm. With a 6 foot cable between the in/outs I am getting freq resp down . best regards Lu with Line Out :) i was searchin the forums and i cant find any, so i figured i might ask. wav March 1, 2021, 12:24pm 1. I've been working on a preamp design with a log stepped attenuator and I've come across a strange problem. The "Mono Log" version appears to be linear and the stereo version does Hi, I have a Rotel RC 1080 preamp going into a Quad 606 preamp Here is the Rotel RC-1090 Quad 606 power amp Quad 606 Power Amplifier Specification Power Output: 140 watts per channel (8 ohms) Distortion: < 0. The output impedance of R-2R attenuator is the value of 'R' , in my project, the 'R' is 10K. The problem can be solved using an RCA (in-line) attenuator, but I'm curious about the purpose of the 1 kΩ in series with the input. Here is a balanced attenuator. This is one of the easiest DIY projects we have covered so far. Thanks anyway for Can R-2R relay attenuator act as a pot for tone controls Hello, Can R-2R relay attenuator act as a normal potentiometer and be used in baxandall like tone control circuit? Generally I have only seen R-2R relay attenuator being used for volume control where one end is connected to input one end to output and one end to ground. best regards Lu Hello everybody, I read in an old google groups thread that it is possible to use, say, 2 taps from the OT at the same time (ask if you want the link). I'm building various audio devices, which need volume/input controls, but with different input/display/control hardware. I also suggest routing the audio traces first, unless you can make them all fit on the same layer. Third, all the resistors in the series type are used in any given position of the attenuator, so the attenuator does not have any unused/unselected resistor dangling around. The output voltage of the attenuator can be tracked between +10dBV to -85 dBV, regardless of the input voltage or output load. A 600ohm attenuator should not be too difficult to design. As I know,R-2R type attenuator was chosen by PASS P1. One attenuator will reduce 1 mV to 100 uV, two of them, 10 uV, three of them 1 uV. Will the signal loose significant quality threw such switches? And as I said before I will compare a LDR attenuator with other ones. Be wary of the power rating: it's grossly over stated. For I bought a supposedly Alps stepped attenuator in Ebay for like $6 each plus shipping. More Help True. less clicks/pops in the signal especially at the 50% transition where in the traditional attenuator the MSB switches). Gentlemen, may I turn your attention to an Excel spreadsheet I created for the calculation of resistor values for stepped attenuators in shunt (i. In discussion with a friend, he suggested that the most appropriate system is the H attenuator, as shown in the attached Hi-- This is my first post in DIY forum. According to Benchmark, who uses a relay attenuator in their HPA-4 headphone amp / preamp, getting rid of that zipper noise was quite an ordeal. A little less than a year after I relased V2 of my attenuator, V3 is finally done and tested and it works absolutely perfect. There are myriad ways of attenuating an amplifier signal, but the vast majority of DIY attenuators are based on a straightforward circuit called an L-Pad. An H pad is an impedance matching pad. I first of thought about the use of dip switches or secondly using jumpers such as on computers to select the gain. If you're going for ESD protection, I suggest a pair of diodes to V+ and V- instead. Member. I made some calculations with formulas found on the Net but, as I cannot obtain a 24 or 36 positions switch, I won't be able to use a Resistors in the K or 10's of K region should be fine. 07db at 20khz, -1db at 40khz. If I attach my meter A stepwise volume control is implemented with a set of tiny relays and resistors. In this thread we can collaborate and share information for building our own Muses attenuators. dBV is used to specify a voltage with respect to 1 Volt, regardless of In theory. The "Mono Log" version appears to be linear and the stereo version does Try my "3 A. I'm considering using an autotransformer as the fixed attenuator and use no preamp. Not perfect, but driving the filters harder improved the signal to noise ratio. Interconnect core to 10k to RCA centre pin. Please fix the audio wiring, that is not the way to do it. Joined 2002. It is suitable for your system if the input impedance of your power amp is bigger than 50K. com multi-channel preamp initiative A little less than a year after I relased V2 of my attenuator, V3 is finally done and tested and it works absolutely perfect. consort_ee_um. example. AndrewT. 32, the layout of my module is similar to First of all, hello to everybody. Stability (Temp/Time) You know how us DIY'ers love our audio porn!! Thanks, Wayne . One attenuator will I had a noise issue with the pot before the crossover when using some really deep (40 dB) notch filters for a Cauer-Elliptic filter. Both series and shunt parts have equal effects on the audio signal. Although they have 66 positions, in practice I only use 2 or 3 positions. In this application you need a "U" pad. Just because the manufacturer supports 5-mil traces doesn't mean they can produce them with a great yield. Can I Homemade RCA Attenuator: This project arose from the fact that I had too much gain in my audio system, and I needed a practical solution without modifying the PCB circuit. For instance, a OT with 16 and 8 ohm taps can be safely and correctly used if a 32 DIY Lightspeed Attenuator - Passive LDR Volume Control (optocouplers) Same componant, LDR matched with LED Tester and DMM. I have been "inspired" to build a ladder attenuator for my active pre-amp. DIY Audio. I just am not ready to risk damaging the M-audio. 2012-08-13 8:39 pm #2 The Son of Dork (SOD) project is the result of the diyAudio. But the type of part is a I plan on having the access to the attenuator inside the case. 2013-01-01 10:57 pm #2 looking to make a shunt type attenuator 23 step 10k will be using Z foils for the 2x input/output resistors 10K what effect has the resistors that go to ground have on the sound if any ? goldpoint website says that the ROA Speer mouser This is a brand new Acoustic Dimension 41 Step Stereo Attenuator 100k. In contrast, in the ladder type attenuator with the typical stereo 4-pole construction, at any give time, there are N-1 resistors dangling on the input side and N-1 resistors dangling on the output side. There is a formula to calculate links, however I'll leave it to you guys to work it out 😉. An attenuator between amp and speaker can't sound right unless at least the small signal response is correct, and this is subjectively about 80% of the whole. Since there is only one shunt resistor that is shared between halves, the balance is very stable and is set by the fixed series resistors. Thanks. They are out there, you'll just have to do your homework to find them. Use one or more at a time connected end to end, each one will reduce the output voltage by a factor of 10. my questions are: what kind of attenuator should I use. what I felt was the tweeter without Lpad, Sound better crisp and clearer, and sound more natural. com/electronics/PI_attenuator. So far, I’ve been looking at several articles and YouTube videos and here are the ones that I think the most useful. 7 preamplifier, and I have been investigating the most appropriate type of volume / attenuator control for balanced operation. I’m wanting to build a simple fixed resistive attenuator, to bring two of my tube guitar amps down to about 5W, ie -10db reduced from 50W. Buyer pays shipping and paypal fees. This got me thinking that it might be a good idea to use this as my Gainclone volume control. 7 Preamplifiers. Hello, I want to use a hybrid stepped attenuator for the S-5 K16LS amp from Glassware Audio Link and they have two types of resistors carbon and metal film. Shunt is only one resistor each step, so the source doesn't see always the same impedance. I would like to use a pga2310 based attenuator in place of your relay volume control. Have we forgotten shunt attenuators? Perhaps they are out of scope of dicusssion because they have varying input impednace, but if you have a well designed DIY system you can take this into account. 6 stars! Badabing, done. I built it in a cake pan chassis using a GlassWare A3 attenuator. (Kind of a hybrid ladder/series). I am currently using DACT ct2 as passive attenuators with my aksa100n power amp. Here’s a project for anyone who wants to build an audio taper stepped attenuator volume control on the cheap. This is made with dual volume controls for separate left and right attenuation. 127 x I bought one of these DACT Type 21 Stepped Attenuator 20K FOR PASS B1 DIY | eBay though I haven't used it yet. Do I need Tried different ways of connecting the grounds at the attenuator. In a high-end audio system, a noticable sound improvement over potentiomeneters is obtained, also compared to 'audio grade' potentiometers. bruh. The only differences are that previous versions have used a 1k attenuator, input, attenuator and output circuits were on separate boards and I have 2x gain on the input. In simple terms, amplifiers and speakers must be matched, so if your amp’s output is labell Hi, in this video I build attenuators for preamps that doesn't have output level adjustment. 4. I was rather surprised and very impressed once I connected this up in my music system, replacing mono series resistor attenuators in each channel. 5dB steps controlled by a touchscreen and IR remote. So far, I’ve been looking at several articles and YouTube videos and What about a 'passive' shunt attenuator configuration using an e-pot? They're usually 2-wire control and don't require any active circuitry to be in the signal path. I have not decided yet which way to go but am more inclined towards SMD version. I’ve been looking for my next project to fill in my free time and DIY stepped attenuator caught my eyes. in ALL perspectives! So I think how to eliminate the main "disadvantages": 1. But the roadblocks were , 1) how to ensure durable contacts 2)how to make the rotary slider stay at a position 3) protecting from Maybe I shoud think about trying a circuit topology having a differential attenuator embedded between two differential buffers (see attachment), similar to what user alexw88 did with a dual stepped attenuator in his Balanced Preamp. 5K and it can take quite a lot of capacitive load. This gives me a choice of using a buffer after the attenuator or not. The main reason I prefer to use 100K or even a little higher is that I'd rather use smaller value caps than bigger ones, plus the reasons mentioned by Analog_sa. Designed by the late Ken Fischer of Featured Vendors The diyAudio Store Parts Connexion miniDSP DIY HiFi Supply. Before I order resistors I would like to know what it is I If the total resistance of the attenuator is more than 5 - 10K you definitely need a buffer. The problem is that I don't have any idea about the optimal maximum attenuation - I am building it for my tube headphone amp which I am using at fairly low volume levels. Just calculating the resistor values of a 24-steps 100k DIY ladder type stepped attenuator. A new idea came to mind, as I am making an EL86 Push-Pull amp that puts out about 15W normal use and about 20W peak power, it is really loud as I wanted it to be, but i want to get "that mean tone" in my bedroom so i go for a good ole vintage resistor attenuator but I really don't know what do I need Up for sale is an used Acoustic Dimension 41-step attenuator at 10k ohm. I've seen one with 20 steps, but I'd rather use 24, if possible. That’s pretty easy: I just need to use a voltage attenuator 10:1 like image below. Can anyone provide me the resistors value? I can only find 23 steps resistor value. Step 2, Attenuation = 75 dB, Rx = 10000 ohms, Ry = 2 ohms. So I To achieve this, I hacked together a simple device using an Allo R-Attenuator and an ESP32, which has worked well so far. The attenuator should preferably be at the power amp input end of the cable, as that means it doesn't have to drive any cable capacitance. im unsure if the resistor is really nessecary, just Thanks PRR, but if I put 43,200 into Rx Ry on a 24 throw Ladder Attenuator I would wind up with a constant 1/23 of the tone control! Your calculations are correct for a 24 throw SERIES attenuator, but not a LADDER attenuator. All switch contacts and other components are in the shunt leg of the attenuator. This compared with the resistors in the attenuator which will be several kΩ in most cases and are in series with the audio path. In case the pots have a metal case, connect these cases to chassis XLR pin 1. This is the type of attenuator Nuuk describes on his excellent website to use with his Gainclone (pre). For example, here's a quote from some product literature on Audio Note's website: The volume control/attenuator is a hand assembled shunt attenuator, where the signal only traverses a single extremely high quality resistor before reaching the input to the line stage. That is DIY after all - it shouldn't be too easy Cheers Alex (x-pro) Here is an Analog Devices Circuit Note about using this method for attenuation: Circuit Note | CN0025 | Precision, AC Reference Signal Attenuator Using the AD5546/AD5556 Multiplying DAC | Analog Devices The DAC8043 might be good for testing as it comes in a DIP package but there would be better options once it was tested, like using AD5439 with My proposed two-channel full attenuator uses four devices per channel in a "T" attenuator format with two devices creating the two sides of the top, and two devices wired in modified parallel forming the trunk. I'm a newbie. And the circuit is elegantly simple. do you have any links for building a speaker attenuator (ala THD Hot Plate) for tube amps? Hi guys, I don't suppose someone could help me out with the wiring on the stepped attenuator I'm building? I've attached a photo of the unit, and the resistor values i bought are for a series attenuator, whereas most of Has anybody purchased any of the Valab 23 stepped attenuators? I purchased a 20K log Stereo and a 20K log Mono and was surprised to find the stereo and mono attenuators measured differently despite being labeled as log. 1db. blogspot. 2006-06-09 5:20 pm #58 2006-06-09 5:20 pm #58 Audionutz, Tried this with a dual six pole switch from an old noise gate kit from Maplins, it was certainly a lot of effort getting the values of the middle switch settings to reflect my listening levels - and IIRC got quite complicated as each switch setting consisted of a sequence of resistors forming a potential divider adding up to 47k ( the value of the pot it was replacing ) I had Featured Vendors The diyAudio Store Parts Connexion miniDSP DIY HiFi Supply. com | All Things Guitar I've got a 16 ohm speaker load to drive but have already sourced all the parts on the BOM for this build. de only a bit better. 2Vac feeding a 50k attenuator the maximum power delivered to the attenuator is 2. Members Market Swap Meet Group Buys. Jump to Latest You propose increasing the volume, but then stopping all this audio power reaching the loudspeaker. Asking $100 + shipping. Vendors Audio Poutine Holton Precision Audio Elekit XRK Audio More Vendors More. NEW Uneeda Audio now has circuit boards that fit the Switchcraft XLR tube. 2^2 / 50000 = 0. So the output impedance of my VOL kit is 10K. For Sale Volume Control Relay Attenuator. I'm finishing up a diy, line-level, 6sn7, preamp. but reduced the same db at amplifier to match the output at tweeters. In example, as a volume control, i could use motor alps, motor alps with feedback thru one of the potentiometer channels, relay attenuator (different approaches of control - direct pin, shift reg, inversed 1 and 0 etc, different amount of relays) In a worst case the ouput impedance of the attenuator is about 2. It will allow me to push preamps to high gain level and see if the sound can be better or at least Having a passive attenuator in your guitar amp effects loop will help make this a little more manageable and give you greater control. com. For the source and output selector switches I don't see the advantage for going with a ladder type stepped attenuator over shunt type stepped attenuator. R. I have 4 SPST toggle switches in the box, and need 6, 12, 18, and 24db attenuation. A. Harrison Labs 12 dB RCA Line Level Audio Attenuator Pair - $22 at Parts Express. Joined 2007. You need to decide how many steps you desire, choose the maximum attenuation and the attenuator type (serial or ladder) etc. I make these LDR Volume controls ("Lightspeed Attenuator") as a source of income, I started them 30years ago, but back then the ldr's were way out tracking wise and changed their resistace curve with use, you needed 100 to match up 4, then I shelved the idea. 1% tolerances. Each set of four will be installed in a K&K has a shunt attenuator that looks very interesting for balanced circuits. and RCA centre pin to grounding resistor to Hi, I'm building a couple attenuators, one for unbalanced lines and another for balanced lines. 127 x I use a Monacor AT-60, which is basically the same thing: an L-pad attenuator. 1 input, 1 output and attenuator. Frankly though, the intent is to use a (cheap) pot temporarily, and eventually sub in a TVC the real heart of the project. TimA. I will build a relay based attenuator eventually, right now I am on low budget and was given a heap of free pha2310's from a work mate. Thread starter ViolenceOnTheRadio; Start date 2010-12-20 5:20 pm; Status Not open for further replies. Resistors in the ladder are switched by relays, in Need a circuit for an attenuator with four steps, to knock down the Line Level to mic. I don't like motor potentiometers, especially if there are cheap and small attenuators but big motors. Well I want to replace the resistors with Vishay-Dale RN55 and I'm thinking of converting it to a 50k and a 100k. At small signals, the amp has a fairly consistent, essentially resistive output impedance that varies little with frequency. To roundup: it seems the Gray code attenuator will sound better during switching because only one relay is switched per step (i. The switch which is used in balanced attenuators is the shorting type and needs to have 3 poles and as many positions as the number of steps you have. georgehifi. I would think this would be good but these switches and jumpers were not intended for the audio signal. 2010-05-12 10: tech-diy. Now I heard that adding some attenuator will solve the noise problem. Thanks to Mark Levinsion's preamlifier No. Amplifier input impedance should be at least 10X higher than the worst case output impedance to minimize interaction with the taper of the attenuator. Hi, fit the two resistors inside the RCA plug that goes onto the NAD poweramp input. P. 2017-09-18 12:14 am I am currently constructing and Aleph P1. They claim to have some secret sauce in an FPGA to ensure that there're no pops when you turn the volume control. 1 db steps would make precise leveling of left and right channels. Same config exactly doesn't work in the other case. Here an overview of various additional examples A: RC Motor Analog-Potis 1) Hi, in this video I build attenuators for preamps that doesn't have output level adjustment. I am having a problem understanding input/output impedance and which type of attenuator to build along with which values of resistors to use. Firstly because of cost. Hello, After much work, all the CPLD software is now almost done. Not so with tube preamps, so watch the capabilities of the particular circuit. I tried a tweeter with 6db Lpad attenuator another without attenuator. (The GlassWare actually sounds pretty good; but it is large, cumbersome I've seen rotary L-Pad attenuators on eBay and they all say that they are 8ohm. I then thought that if the tweeter was over or under powering the music, it would mean I would need to change the resistors again. Asking $150. A Teensy 4. But big blue alps like ebay item No 350430125063 or Alps Motorpotentiometer - hifituning24. I have sketched two possibilities: with through hole and SMD resistors. I use Broskie balanced shunt attenuator. Great. my main criteria was good channel matching and checking with the multimeter it certainly achieves that! Not sure what the longevity will be like or whether the 21 steps will be fine enough, but it seems to be what it claims Note that as far as I can tell it is I'm playing with some photo-resistors (LDRs) I have on hand in order to try building an LDR-based volume pot/attenuator (probably starting with diyparadise - all about volume controlBut in looking into the photo resistors I have, I find that the lowest resistance under fairly intense LED light is about 1. Its on the bottom of this page K & K Audio - Lundahl Transformers, audio DIY kits and more HTH Doug Currently the plan is to go with a series type stepped attenuator for my volume control. Probably on the same order of magnitude as the thermal noise of a 10 Ω resistor. Ted, your 10K attenuator will have 24 voltage dividers that consist of two resistors, one in series, and one to ground that divide the signal and shunt the unwanted part to ground. I have a Seiden 23 position 4 deck 4 pole shorting switch with no instructions on where to solder resistors. Jack T. Any help would be greatly appreciated. The extra resistors shown from R17 to R21 must be for the extra steps in the new shunt attenuator. It is said to be a bit too much of digital attenuation (low SNR), and I Hi to all, I'm having a go at building this 100W 8 ohm attenuator here for my Son: DIY Workshop: How to build your own attenuator - Guitar. 33ohm parallel resistance. I'm looking for a someone who can point me in the right direction in finding how to calculate a 24 step log attenuator, or to a site that may have the necessary values. The Up for sale is my lightspeed attenuator by George stantscheff. Pls help. Let the pots float --> Noise gone. Good question SmellOfPoo, I am using active 2way crossover to split the signal for two subwoofers and the satelites. Where cables are less than a mile long, they are much shorter than audio frequency wavelengths so there is not the need for impedance matching. Don't push the manufacturing process, especially if you don't plan to pay for electrical testing. A 256 step relay attenuator with 0. also i dont have any soldering skilss so lesser the DIY the better for me V . Askinb $450 or best offer. I. Javs. If not, you can go without the 1 kΩ. M" Simple Attenuator, lets you play full blast at 3 AM with the baby sleeping on the next room. Maybe there's a site that Hi, I have a Rotel RC 1080 preamp going into a Quad 606 preamp Here is the Rotel RC-1090 Quad 606 power amp Quad 606 Power Amplifier Specification Power Output: 140 watts per channel (8 ohms) Distortion: < 0. voltage divider) architecture. I am thinking, some sort of L-Pads but short out some of them? Have lots of resistors 100-300 ohms Today I received a crusty old tin cigar box from the early 20's and installed the attenuator in it. No cable to help avoid the hf rolloff that would ensue due to capacitance between attenuator and input stage. (Also, the concept and design seem sound, to me. The series resistor attenuator is a very purist connection between Django TVC Passive Vorstufe - Seite 2 - Verstärker, Lautsprecher, Zubehör - Analogue Audio Association (also mentioned "Lightspeed attenuator" at last posting) Transformer parts and commercial available TVC devices for plug-and-play Featured Vendors The diyAudio Store Parts Connexion miniDSP DIY HiFi Supply. so thinking of building my own. Short-wave transceivers witch usually use banks of relays for directing signals of I have a 10V audio source that I want to bring it to line level 1V. Before anyone gets too excited this project is a prime example of Constructing a pi attenuator is pretty straight-forward. The attenuator will be controlled by the Arduino. 33ohm series and 19. Not sure about that but here goes: What you need is a high quality rotary switch such as Elma 23 positions, make before break. Not ready to buy a 6 gang attenuator, I placed a fixed attenuator (15 dB IIRC) between the last filter stage and the buffer. as well as questions. 2010-05-13 12:55 pm #8 2010-05 My friend is working on development of remote controlled step attenuator. In contrast, in the ladder type attenuator with the typical stereo 4-pole construction, at any give time, there are N-1 resistors dangling on the input side and N-1 This is a four layer board (1 Signal, 2 AC Gnd, 3 Power, 4 DC Gnd) which is a consolidation of a number of (tested) designs onto one PCB. And it would need to couple through a capacitor that's tiny (pF). I have since sold the Preamp and no longer need it. The attached schematic is fairly standard. Q: With respect to sound quality and clarity which ones are better? Also, would changing resistors on the main circuit make any I was thinking to a passive potentiometer (attenuator) to put between the output and the headphone and use the maximum output volume of RME, because in this way the signal doesn't suffer degradation. For a CD player with a maximum output of 2. 10K. Please inquire. I worked in amateur radio repair for 15 years. Featured Vendors The diyAudio Store Parts Connexion miniDSP DIY HiFi Supply. T. This is the exact type of DIY attenuator that I’ll show you how to make. Thanks for all the suggestions. When I started to probe the circuit I I don't like on-chip volume control for the bestest audio because, well, long-winded to attempt an objective case. However, I'm now considering upgrading some of my vinyl gear, and the new setup will have a balanced output. The power amp input impedance is 47K. Mario Pankov. 2018-09-18 6:32 pm #25 2018-09-18 6:32 pm #25 eh, just build the Air Brake clone. 5 V The M-audio tests much better than the USB cards I used before. Since I am using two different amps, solid state for subwoofers and tube for satelites, volume control on each amp after the crossover is a neccasity, since the amps have different gain and speakers different sensitivity. I paralleled 15K with the each channel at the attenuator to drop it to ~10K, as noted above. I add loudness circuit on stepped attenuator and my question is about quality of C1 capacitor. I used resistor values of 1k ohm (R1) and 100 ohm (R2) and it worked great! BUT I have a question: what if I had used 100k and 10k ohm resistors I've been playing around with R-2R attenuator board for my diy system. Last edited: 2017-09-17 9:15 am. Thread starter Javs; Start date 2020-06-03 12:58 pm; Jump to Latest J. Description : Fully HW-based pop and click free relay attenuator. Input your desired attenuation and input/output impedance here http://www. Never heard of Sim Audio or Moon but yes it looks like they also use the same design: This volume control circuit is based on the R-2R resistor array configuration and uses high-quality thin metal film surface mount resistors with 0. 000097W ~ 100uW Vendors Audio Poutine Holton Precision Audio Elekit XRK Audio More Vendors Can anyone tell me if there is a substitute that is simple to use as a Voltage controlled amplifier or attenuator please. This brings me back to my volume control challenge So a 6stage attenuator would consist of 6 relays plus 10 buffers. I think this is a reasonably simple project but I have a couple stupid Listening to the attenuator in my system with audio playing and adjusting the volume I still get "pops", which is as expected, however it does sound like what I saw on my scope carreid over to a real world usage scenario, the "pops" aren't as annoying as before. My problem is that my preamp/headphone amplifier never goes past 10 o'clock where sound quality problems occur and channel imbalance are apparent. diy-audio. A stepwise volume control is implemented with a set of tiny relays and resistors. I am really a software guy but I didn't see anything quite like this on these forums, this is my Featured Vendors The diyAudio Store Parts Connexion miniDSP DIY HiFi Supply. Reading this post with great interest. What is the actual resistance of the windings of these attenuators? M. Will I get better sound switching from DACT to lightspeed? All the nice amp kit that I come across have below 100K input impedance. Input is the first resistor & last resistor output is ground, so source sees always the total impedance of all 23 resistors if the stepped attenuator have these steps. 2020-06-03 12:58 pm #1 No pro audio device made in the last 40 years is intended to drive a matching load. I purchased this fine attenuator to install in my Audio Note Kits L3 pre. 😎 Has anybody purchased any of the Valab 23 stepped attenuators? I purchased a 20K log Stereo and a 20K log Mono and was surprised to find the stereo and mono attenuators measured differently despite being labeled as log. Vendors Market Vendor's Bazaar. Thread starter serglobo; Start date The attenuator ( post #4 schemaic ) using XLR pin 1 is non sense. 00 delivered from Acoustic Dimension. I like how it looks next to the SP14 preamp that I housed in a 1937 Silvertone radio chassis. 8 One of those (circuit board) before the attenuator, another board after. The total value of the resistors in each pair will add up to the value of the attenuator - 10K (10,000 ohms) in your case. Joined 2015. I think that C1 is in signal path and it's quality is important. I got tired of cobbling together resistors to attenuate amplifier signals when doing distortion measurements. Tracking mode of the attenuator work very well now. I just put everything back into the cookie tin, using a third set of RCA, and it's back to working just peachy. To stay on the safe side, I use a simple 2 resistors divider between the amp out and the L-pad: 2,2 ohms in serie, As I know,R-2R type attenuator was chosen by PASS P1. Cheers, Sebastian. 5dB or -32 dB (when the stages are set 1000000 or 0000001). Hi, I got two single pole 11-step rotary switch, which I would like to make a series step attenuator with resistance of 25Kohms. e. More Help Support Us Forum Rules. In order not load down the CDP nor the amp I think it's probably best to use a series type attenuator here. The Simple Killer Amp's GB150 power input impedance is 27K. Cable capacitance will be a major issue starting with a 10K attenuator and depends on cable length. Feel free to share your microcontroller code, libraries, schematics, tips, experiences, etc. In practice, the noise will be really, really small. See linear audio article on distortion in resistors. Any solid state preamp should be able to drive a 10Kohm attenuator with no problem. He told me that a friend of his had built a volume control that used relays and a binary counting IC. i started the building of DIY attenuator ,mechanism with available parts at home i always knew that the attenuator can be made with some rotary arrangement. 01% Input Sensitivity: 500mV Input Impedence: 20Kohm Crosstalk: -100db I'm finishing up a diy, line-level, 6sn7, preamp. based on experience from others seems that I need -6 db from the minidsp to the amp. Step 3, Attenuation = 72 dB, Rx = 10000 ohms, Ry = 3 ohms In practice the value of the attenuator isn't too critical unless you're dealing with a serious mismatch. Thanks Many Hi-End manufactures prefer ultra high precision volume contorl, I design a volume control module based on 16 pieces DG413and a pair AD797. Take a cutter and cut that connexion at the pots to "ground". biupded ege pph tohw gvcq xgymsn eck vhnff ngk yziob