This topic has been brought up before in various versions, but here we go again...

So I have a bunch of 2-channel amplifier modules that I harvested from a Crestron CNAMPX-16x60. These are class AB 60W into 8R, 90W into 4R. In the amp there are 8, 2-ch modules for a total of 16 channels run from two large toroidal transformers. With the amp disassembled I am planning to use these in active speaker projects.

In one potential speaker system, I would like to use a 4 Ohm subwoofer but 90W is a little on the lean side in terms of the power requirement. So I am dreaming of using a pair of the 2-channel modules to create a bridged-parallel connection to the sub.

Just to get it out of the way, I understand about load sharing, gain mismatch, and DC offset issues. I will try to trim gain and match DC offset between channels, and was envisioning using series resistance on the order of 0.22R on the output of each channel. I will drive each pair of (+) and (-) channels using an audio interface with the (-) channels inverted.

This seems relatively straightforward, as long as some caution is used, however, I would be reassured by some practical and gentle positive feedback from the great minds of the forum. What sez ye? TIA.

Hi All,


I need more amp for some new speakers (100W, 91db/2.82V) and I'm thinking of foregoing my typical affinity for tube amps to try something different. I'd like to hit 100W at 4 ohms just to be sure I have maximum headroom for peaks but this is negotiable. The F5 is a nice easy build that gets me 40W at 4 ohms but I'm worried I will regret not maxing out my headroom. A turbo V1 gets me to my the target wattage but has more unknowns for me to deal with. So, I'm a bit torn between the ease of building a standard F5 and the potential complications of building an F5T (note that turbo boards are out of stock as of this post). I've read through the F5 and F5T docs several times and burned though hundreds of pages of posts and it's all sloshing around in my head so please help me get a few things clear:

• The F5 doc specs distortion at 40W into 4 ohms as .2% but does it clip there or is there a little more power albeit at a slightly higher distortion level?
• Can the 4U deluxe chassis from the store handle the dissipation of F5T V1 if I ever want to reuse or modify?
• Can the Linear Systems jfets in the store handle the higher rail voltages of the turbo without cascoding or is that reserved for Toshiba parts only (with some established risk)?
• Early in the turbo document, after suggesting the higher rail voltages in a standard F5 circuit, Mr. Pass says, "Want to drive 4 ohms with this? You can do it, but I recommend that you consider the upgrade to the F5 Turbo V1". I'm wondering what are the consequences of running 4 ohms at higher voltages - particularly if you are not pushing the volume most of the time.
• Would parallel output devices or reduced source resistors increase power into 4 ohms at all? I'm thinking not, but would like confirmation.

So, what you can probably ascertain from my questions is whether or not I can build a standard F5 today and keep a relatively short path to a turbo later, or if I can do something between a standard and turbo V1 now. For example, I could see myself hacking in a second set of output devices later without swapping out the boards, but adding cascodes not so much. Swapping out the transformer and filtering would be costly but easy, a new chassis not so much.


Sorry for the lengthy post but I've already spent several days running in circles and I find myself unable to pull the trigger on parts.


Brian

I'm getting a ground loop hum when the 12v trigger wire is connected between the preamp and power amp. I have ruled out everything source wise and tried an earth ground between the two components without success. If I remove the ground connection completely from the trigger wire gets rid of the hum and the trigger still works. I know running without a ground is not great solution if something should ever go wrong in the trigger circuits of either the preamp or amp.

Putting a 480ohm resister in series with the ground should still allow the circuit to complete but break the ground loop. Question is, is this better/worse than no ground at all?

I have a pair of F3 PCBs from Peter Daniel's run a while back. For some reason I thought I'll build 2 ...

$20US, plus postage from Australia?

Hey there,

I am planning to make a CRT oscilloscope to use on my audio projects. I am not an engineer but learning analog electronics... I would appreciate a lot if you could help me a little bit on building it. I am planning to make it from scratch.

I am willing to use a 3LO1I (3ЛО1И) tube
Here is the information I have found on the tube:



Right now I am trying to build the right power supply to power the tube. I will right here my process.

Thanks in advance...

Single. Please email me. Thank you!

Hello
I have been restoring my PS preamp 4.5 circa 1986. With all caps replaced, the constantly flipping of the PCB came with the output selector switch cap being unsnapped. The face-plate markings: On/Off, Straightwire, CD. Phone have 4 indents. I lost the ball bearing but retained the spring. I have located the ball-bearing size on line as well as direct replacement bu Lorlin. Problem is I do not know how to indent the switch to those output markings? There are 12 slots behind the blue covering. Also, There is a cap 2200uf 16V axial by the TIP transistor which originally is soldered to a bare wire bridge on the negative side and a PCB hole with no connection. May of been just a solder eyelet but with no connection? Is this so? Help.
Anthony

I want to make a switcher for digital audio signals (S/PDIF) that I can control from an Arduino.

I happen to have a stand-alone digital audio switcher so I thought I'd trace out that schematic and see how it works.

I'd appreciate some help understanding how this circuit works and why it is done this way?

The majority of this is pretty simple, the input obviously goes to a 74HC4052 (two of them, because this switches two independent outputs) which are high bandwidth analog switches. After switching the signal is fed to a 74HC04D which is a Hex inverter. Am I correct thinking this is simply to buffer the output?

The main bit I don't understand is why they have this resistor divider around the hex inverter. I can see they are chaining two sets of input/outputs in series to get back the 'non-inverted' signal, but why the resistors?? Can someone help here?

Thanks!

I made a reciprocating dirt sifter out of an old saw motor for my wife. The 24V power supply I had purchased off ebay to run my audio amp didnt work out, but it powers the pictured contraption at just the perfect speed. (Was using a Variac, set to "45")

We went to the nearby woods with the wheelbarrow this morning for some live organic dirt, in an attempt to inoculate a compost pile. Sifting out the roots, stones and leaves she found an arrowhead!

What are the chances?

Some time ago I planned to build a pair of Fonkens (http://www.planet10-hifi.com/) and here are some preliminary views.
Burch plywood is used and the results are very satisfying.
Still have to stuff them with damping material, screw in the speakers and wire them before I can listen.
I’ll report when done.

/Hugo

Hi there,

My CD85 has problems in the transport. Won't track further than track 1 or 2, sometimes 5.

Sometimes doesn't recognize disc at all, and sweeps the laser unit around at madness. Not a nice sound.

I have to find out what's wrong with it.

Can anyone help me finding a service manual for this baby?

A philips CD880 is almost similar, so this service manual would help as well.

Thanks,

Arjan

Hello Everyone,

I'm making an 4-way active open baffle, ww/w/m/t. My current issue is I plan on using two 12" woofers per side with a crossover of 200hz for the low end. I will be using DSP to control the crossover using FIR and phase/timing. Based off that, I'm confused as to how the sound waves interact with two woofers compared to a single one.

Do the sound waves multiple and act as one or are there other things to account for?

My plan is to time/phase align them to the rest of the drivers, but they are not going to be individually controlled but wired together.

Do I angle them to have mechanical time alignment or can I just dsp them as 1 speaker without having to angle both of them.

Hello, I am looking for a mid-woofer for a ported enclosure of about 11 litres net volume and have shortlisted the following 2 drivers:

(a) Scanspeak 15W/8531K00
(b) Hiquphon OW1

I have selected the 8531 (uncoated) version, over the 8530 (coated) one for two reasons:

1. I believe its lower Vas and higher Qt make it more suited to this small enclosure.
2. The response plot seems a bit smoother up to the rise that both exhibit between 1-2 kHz.

Having read lots of posts on here, the 8530 unit seems to be very highly regarded, although there seems to be much less written about the 8531 one. I also saw that the Carrera from Meniscus Audio uses the 8530 and OW1 combination but in a 15 litre cabinet.

Does anyone think the slightly earlier rise preceding breakup of the 8531 is the reason for it seemingly being less popular than the 8530?

If so, I see lots similar units from other manufacturers that go much higher before breakup. For example, the response plot for the SB Acoustics SB15MFC30-8 is level to almost 4 kHz although not quite as smooth as either of the Scanspeaks.

I also note that many of the other units cost a fraction of the Scanspeak ones!

Therefore, I would like to ask:

• Are these Scanspeak mid-woofers really “better” than their rangier competitors?
• If anyone thinks that my choice of the 8531 over the 8530 is flawed for this application.

Any help would be appreciated.
Many thanks.

PS I am very keen, have read quite widely and think I have grasped some basic theory, however, I have very little actual experience!

https://www.scan-speak.dk/datasheet/pdf/15w-8531k00.pdf
https://www.scan-speak.dk/datasheet/pdf/15w-8530k00.pdf
https://www.sbacoustics.com/index.php/products/midwoofers/mfc/5-sb15mfc30-8"

Hello,
want to build a PP pre with E80CC output tubes and have a plate to plate 10K Ohm, 600 Ohm secondary trannie. Have read some literature about calculation of the correct working point of the tubes for class A, but have some difficulties to understand the topic.

What I understood is, the correct primary impedance has to be calculated for the double idle current of one tube. So in fact, if one chooses 150V per tube and 4mA per leg of the trannie, than it should be 8mA for one leg and 150V. Result for this operatin point is 18K Ohms.

Could somebody please correct my calculation, if wrong.
Is there a possible class A working point for this tube that I could make use of with this 10K output trannie? Max. voltage of the power supply will be 300V, current is freely available.🙂

Hi everyone! This is my first thread in the forum. I am very happy to start a new part of my audio life. First repairing, and maybe one day building speakers.

You will quickly realise that I'm a newbie. The situation is the following: I got a 70's combo turntable, which sounded horrible. Thinking it was the reason, I exchanged it with a 80's Technics SL-DD33. It sounds way better! BUT... Now, because I have Sony STR GX-311 receiver which actually works, I realised that there's a problem with one of my loudspeakers. As the title says, the speakers are a couple of two-way Pioneer CS E320.

The problem I heard is that the right speaker sounded muffled, not as bright as the left one. When I changed the routing, I realised that's is not the receivers amp problem, but the speakers. Then I though "Muffled.. Not as bright.. It must be the tweeter.." So I ordered two Dynavox DX159 Tweeters. Today they arrived, and to my surprise, they didn't fit in the wholes (great..), and when I plugged them in, the muffled sound was still there! (great again..).

Now I think this is the project that I needed to finally learn how the whole signal flow from a speaker works, and be able to make some minor repairs. It seems to be a simple enough project to start with.

My questions are:

What would be a first approach to troubleshooting the speaker? I'm planning on making measurements with test tones. I will upload my results in the next days.

Is there a possibility that the muffled sound is caused by the crossover components?

I see that in the crossover there is a TOWA 63v 7uF capacitor, and there's what I believe 2 inductor coils (1.5 mh, and 0.26 mh??). Do this components age? And differently one amp from the other?

Can someone point me in the direction to a thread explaining how to measure drivers and with which software? Maybe the woofer is also working weirdly? It is a 20-716F .

Thank you in advanced.

Greetings,

I am looking for some advice on a project I am building. I have several knobs and switches attached to an enclosure, i have spent a few dollars on building the chassis, and will be coming to the point to adding the description of what each function.

Any advice on how to do this? Press on numbers?

All assembled and tested
Universal USB to I2S Interface Indicator PCB+Arduino Nano+OLED 1.3" include Isolator Si8065AA-B-IU
for Amanero Combo384-DIYINHK XMOS-JLSounds I2SoverUSB-Luckit WaveIO
more details :Universal USB to I2S Interface Indicator PCB | Dimdim's Blog
Price 40 euro

Most of us nowadays are using USB to I2S interfaces to "feed" our DACs with music. Most of these interfaces have a way of letting us know of the type of signal they are sending to the DAC (PCM or DSD) and the signal's sampling rate via supporting a number of LEDs, corresponding to the signal types and sampling rates.

A while back at avclub.gr I pitched the idea that we build a more universal sampling rate indicator, one that would display the sampling rate on a small screen and be compatible with most of the USB interfaces out there.

It would be open source, based on low cost Arduino hardware and be easy to build.

The Arduino would be galvanically isolated from the USB interface so as to minimise interference.

With these basic specs in mind, I proposed an Arduino Nano with an OLED 0.96" or 1.3" screen. I proceeded to write the relevant code, aiming to support most of the popular USB interfaces like the Amanero Combo384, the WaveIO, the DIYINHK XMOS based interfaces and the JLSounds I2SoverUSB interface.

Along the way it was decided to add support for basic IR control, such as power on/off and basic source selection.

This was the end result, still in the breadboard stage:



We decided to design a small PCB that would ease construction, since the isolators were QSOP-16 parts (only available at this footprint unfortunatelly). I did the circuit design and lemon did the PCB design work. We ended up with this circuit:



And this PCB:



This is the indicator in action, connected to an Amanero:

https://www.youtube.com/watch?v=Xxqe_1sWpkg

You can find the Arduino code at the bottom of the page, here: Universal USB to I2S Interface Indicator | Dimdim's Blog
(sorry - for some technical reason I can't give a working direct link to the file)

A lot more info (BoM etc.) on the circuit and PCB can be found here: Universal USB to I2S Interface Indicator PCB | Dimdim's Blog

It is relatively easy for me to support more USB interfaces, as long as they have the necessary I/O and documentation. I welcome requests. 🙂

I'm in the process of finalizing aspects of my computer desk amp project, chassis making, layout, bread boarding, etc. I'm now entertaining the thought of using DC for the pre-amp stage filaments (6J6) and have extra current to experiment/listen with trying the power tubes (6BX7) as DC vs AC.

I would like some advise on when to bother with regulating and when its not necessary.

I understand that with DH filaments there is a great advantage of using a regulator like the Coleman regulator. Because the filament IS the cathode and all that that implies.

But for tubes with separate cathode and filament would you put a premium on voltage regulation for the DC supply? Considering the extra space you need for an external heat sink and the extra current/voltage you'd need for the regulator cutoff, etc.

For non DH tubes, is a 1950's style RC filtered supply, except using the large uF capacitors now available (that were not available in 1950) good enough? Filaments prefer current regulation correct? Yet the many circuits I see use a simple voltage regulator, few and far between are current regulated as I peruse schematics.

In laying out my chassis (actually a wood/aluminum box, think 1960's tube table radio-like). I have an area reserved (2 inch by 4 inch) for the DC supply components/board inside. And I have an area on the back where I can hang a flat heat sink up to 4 x 5 inches. Which is quite a lot of heat sink! This is good because I want to use this same form factor for other projects, when I get out to the table saw I will probably make 4 of these cases for my next 4 projects.

So my dilemma is do I go regulated or un-regulated? Is the payoff for going regulated really worth it over a really good low ripple RC supply?

I can obtain a middle ground in DC current regulation (without using a regulator) by upping my filament voltage to maybe 9V DC and inserting a large resistor to bring it back down to the 6 volts. (that cost is heat not space). I have total flexibility on voltage because I have a space for a dedicated filament torroid, so I can buy any voltage of filament torroid I may need and just plop it down.

Thanks for weighing this, I want to learn how to do things not in absolutes, rules, or biases like "I always do this, or I always do that, just because".

Happy workers day next 01/05 for those who are workers and celebrate this day.

Meet Beepo: it is cheap and expendable yet robust, frugal but effective.

It mimics old-style tester like this one:



These electromechanical testers were quite effective and much loved, but they had a number of drawbacks: they were not very deterministic on the continuity threshold, and they happily passed 250mA or even more through the DUT, which is not very safe in modern, sensitive electronics.

This design (based on a previous version) keeps the advantages of the mechanical device like robustness, simplicity and absence of power switch but without the drawbacks: the current through the DUT is more than an order of magnitude smaller, it does not generate inductive spikes and is even faster:



The circuit is terminally simple, and looks like some lousy multivibrator but it shouldn't be dismissed too quickly: it does its job with a redoubtable efficacy: it works consistently from 0.9V to 2.0V (a single cell), consumes zero power when idle, responds instantly and has a deterministic resistance threshold of 3.5Ω.
It is also capable of almost magical feats, but more on that later.

The connection to be tested acts as a power switch, meaning an idle consumption limited to the leakage currents.
The circuit is simply an oscillator having a well-defined oscillation condition: (R5/R1)*(R2/(R7+Rtest))>1 (neglecting the dynamic resistances of active devices).

With the values shown and the parasitics, Rtest needs to be smaller than 3.5Ω (it can easily be modified).
Other than the resistors values, the circuit is extremely tolerant and will accept any type of semi and capacitor.
The capacitors determine the oscillation frequency (3.5kHz in this case) and can be altered to suit any preference.
It is reasonably well protected, and will survive a test of a charged capacitor (not at 325V though).
Thanks to its resistance discrimination and fast response, it is possible to test reliably and quickly multicore cables, large connectors, etc.
The supply source can be a NiMh, alkaline or saline cell: worn-out cells can be recycled because operation remains possible below 1V.
The cell can be soldered in place because the average current consumption is extremely low.
With a NiMh or NiCad element, the test terminals can work as a charging input thanks to the protection diodes.

Here are some pics of my prototype:

Dear all,
I'm Max from Paris, I'm a music lover and I try to get the best out of my not expensive hifi gear.
Thank you to you all for the huge amount of usefull information we can find in this forum.

Stay safe and wash your hands.

Max

Hi there. First time posting but I have been lurking for a few months now and finally pulled the trigger on a pair of Alpair 7.3s. I plan on using them in a desktop set up and when space/set up permits, I may look into different cabinet designs.

For now, I am torn between the Slim Classic GR and the Wide Classic GR. I read in a previous post that the primary difference between the wide and slim has to do with baffle-step loss. The speakers will be 5 inches from the wall so logically I require a front or side port which both of these designs include.

1) Am I correct in understanding that the wide would perform better this close to a wall?

2) Does the side port have any effect on tuning etc. vs the front port and should the side ports face each other?

3) Is the tuning of these boxes similar to the Mark Audio GRBs? Fb=52Hz

4) What are the benefits of having the drivers off-center? I like it aesthetically, I'm just curious as the Mark Audio GRB plans have the driver in the center.

I appreciate anyone's feedback and look forward to getting this project underway. It may take me a few months to a year to select a bloody stain but I hope to have these cabinets completed before the drivers are broken in.

Thanks!

Well, I'm bored in isolation, so I'm going through my projects. I have an HK ca260 that exhibits very strange behavior. At very low volume (and I mean just a couple clicks up on a head unit.) The audio is very choppy, and weak. If you turn it up a bit, the audio comes through, but it's not right. I discovered that if you touch the can of the coupling capacitors the audio clears right up even at very low volume. (I was bending one over to put my scope probe on it) but of course it adds 60 cycle noise like crazy. I've replaced the coupling caps, and it may have helped a little, but not enough to brag about. These have a very strange power supply in them. Anyone have any thoughts? It's both channels, which screams power supply to me, but all the voltages are there and stable.

The amp I am building has a wood front and my pots threads are flush so I am unable to put a standard nut on it. What type of nut is in the picture and where can I get one? On eBay it says the pots thread width is 7mm. At the moment the pot is secured with a wood screw and although it’s not going anywhere it is not ideal.

Today the power supply for my KBL went up in smoke and blew the fuse. There's a completely burnt resistor and a shorted diode on the board. The associated regulator transistors (15030 and 15031 pairs) seem to be OK (they're not open, not shorted based on testing with ohmmeter) . Unfortunately I haven't been able to find a schematic. The design seems to be dual pwr supplies with seperate transformers, each is balanced and just differ in voltage. My repair strategy is this:

• Replace the toasted parts (resistor, diode).
• Replace corresponding components on the 'mirror' side of the circuit as well
• Also replace ALL the electrolytic capacitors since the unit is about 20 years old. Since the unit is disassembled it's not that hard.
• Leave regulators alone since they seem to be ok.

Does this make sense? The 100% recapping may be going overboard but I have no way of knowing which caps would be the prime candidates for failure in the future. I can replace regulators too, they're pretty cheap, but I'm not sure that they're a weak link.



Any comments would be very welcome. Thanks in advance.

This is our 2A3 single end class A integrated amplifier which is designed and made on the basis of the classic 2A3 circuit, 6SN7 double triode drives 2A3 in class A single end with 5U4G rectifier. The output power is 4W. 2A3 is a direct heated triode, but unlike 300B, the sound of 2A3 is more transparent, dynamic and fast...

What gives here?
All measurement seem correct until I rectify. 35v secondaries showing what I might assume....but the DC is coming out way low....like 20volts low. Should be 51 or so (this is for a tpa3255).

I thought maybe it is an RMS thing with my DMM but even so the numbers dont add up.

Measured the BR in diode mode and got 0.9 between both 'sides'...whatever this tells us....assuming the voltage drop of 2 diodes so I will have lost 1.8v through the BR.?

But where did the other 18v go?

So I have run into an recurring issue- I need a part that is no longer made. What can I do about it?


I have a pair of PA speakers. They are fairly old but up until now have worked flawlessly. The other day one of the caps popped. (C1)



It is a Aluminum Electrolytic NP 15uf 50v with 10mm spacing (big filter cap)
My issue is they don't seem to make these any more. My options seem to be limited to either changing the value and replacing them in both speakers, or trying to patch a few together to meet the requirements.


I'm not a wizard with electronics, I know enough to be able to fix it when I have some clear precise instructions.


One person I know suggested that I use two 30uf 50v in series where I solder the - leads together :source to +cap to -cap to - cap to speaker.


Does anyone agree with this solution? here is why I ask- Will this change the sound of my PA speaker enough to make it a noticeable difference?


Will I need to do this with both speakers?


Are there any better solutions out there that wont involve buying new speakers or spending lots of $$


here is a photo of the exact same board. I'm trying to resolve C1. the other two caps are 2.2 uf 50v and the the resistor is 10w 10RK



Thanks!

Hello 🙂

I'm thinking about building a Class A integrated, or an A/B strongly biased towards Class A.
I currently own a Nad C326 BEE (with upgraded caps) and would like some more transparency, without losing warmth...

- It will feed a pair of Seas A26 (home built, I opened a thread on this forum), which are speakers very easy to drive
- I don't need too much power, my 50W Nad rarely goes over 10 o'clock and I can't remember I went above 11 o'clock... So I guess 30W or even less would be suitable.
- Budget is not unlimited, I'd say under 500€/$.

I'm interested in the Sugden A21 so far....
Are there any kit for this particular design?
Or would you recommend another design?

Maybe should I start with the amp section in the first place (together with the preamp section from the Nad which is maybe not its weakest point) ?
Or should I go for the preamp as well?

Anyway, any advice would be welcome!

Hello

Presently, I rebuild monoblocks Melos amplifiers. The output stage tubes are 6KG6/EL519 tubes driven by a mosfet follower. Between the mosfet followers and 6KG6 grids, there's 20K standard wire wound white ceramic resistors. This is the first time I see such a high value grid stopper resistors. Why they use 20K resistors ? (oscillation problems ?) During the rebuilding, I thought using standard value like 1k non inductive resistors. What do you think ? Thanks.

Dear all,
I am brainstorming again, looking for some sort of protection for the 3" fullrange units SB10PGC21-4. If I am going to put something in front of it, I thought about adding something that could improve the CD of this speaker, specially at HF

I saw some speakers and experiments that use a phase plug sustained in front of the driver, and I was thinking about using our lab 3D printer to make some prototypes. I just made a rough sketch on this nice Friday afternoon, but it is too late now to turn on the printer and have this ready before going home 🙂

But, most important, can you recommend me any literature on this?

many thanks, Erik

Hello all

I m new to PA drivers and amplifier so i need some help

My system is PC based , one DAC with RCA connectors , one amplifier to run full-range drivers and one Behringer NX3000 to run 4 x 15 inch drivers in OB configuration . What is the best way to connect all ?

thanks

Cute

Lots of scenes, a mom ballerina w her kids, etc., etc.:

YouTube

For Sale :-

OPA1656 Op-Amps mounted on 8-Pin DIL Adapter.

Genuine TI chips purchased through Mouser and assembled in the UK.

17 Euro or 14 Pounds Sterling each, including shipping.

Minimum order 2.

EU Countries Only.

An acquaintance gave me an early Wave Radio with integral CD to see if I could fix the low volume problem. It appears the control chip may be faulty because now the display will produce a "Please Wait" message and no audio from any source. I tried the several reset methods, but to no avail. Apparently, this is a common failure mode. Any ideas?

I'm fairly sure it'll have to be replaced; I'm not going to waste too much time on an old, over-priced product. If you have a recommended replacement, I'd appreciate any advice. The unit will occupy a shelf next to a galley kitchen in a small diner and should be on the compact side. I'm not up on smaller boom-boxes with decent sound so I'm hoping to find an experienced opinion here.

Also, it appears that later versions lost the R-core tranny and consume half the line-current. Any clue about output power; I'd guess 5 - 10wpc max. Thanks for any input.

Just saw the Aleph J transistors are back up in the store but the boards are sold out! I am assuming they will make more but not sure on the timeline, anyone have a set they are not using?

I am at my wits end and its eating me. So I built a new version of my old amp, fancier chassis, better OPTs. And its working great. But I took the old amp (that has been working flawlessly for five years) in to my workspace and thought I wanted to play a little with it. Tube rolling for one. Put some 6n6p in place of e88cc AND somewhere along the way - moving from the living room to my working room (not calling it a workshop, cause it isnt) and putting new tubes in it something has happened. Only one channel is playing. Playing fine, no hum, no hiss and the other channel is just dead. Tubes light up fine on both sides. Anyway, its not that I need the amp anymore but I figured it could be some training to get it running so I have changed the entire PCB (I have several) newly populated, only thing I had to move from the old one was the coupling capacitors. Same thing. Changed the input RCAs. Changed to another set of OPTs. Changed back to the old ones. Same, same, same. One channel is dead AND I have 80v AC in/on? the chassis and I can not see where that is coming from. I just cant understand. Anybody get any ideas what I should check. BTW I do not have any fancy instruments. Only a universal meter.

This is a specific question. My workplace is located in a poorly constructed building and there's an office above me, where people occasionally stomp. The worst part is heeled shoe women loudly stomping on some parts of their floor (my ceiling), where the entire room just booms loud. There's also the annoying heel loud click, but it is not so severe and can be drowned with music.

I could not manage to get along with these assholed people, so my only option is to move or somehow kill that bass resonance. It seems to be at a specific frequency, so I wondered if a Helmholtz resonator tuned at that specific frequency might help absorbing this frequency peak?

Hi everybody, planning a 3 way bookself. I dont want earth shattering bass, so no subwoofer. My plan is to use a 5 inch woofer, 3 inch full range, as i already own it, and 3/4 inch tweeter driven by 2nd order crossover and tpa 3118 class D amp.

Earlier thought of a single driver system, so TC8FD05-04 - 3" Paper Cone Full Range is purchased. Now, i am going to purchase SB Accoustics SB13PFCR25-4 5'' Paper Cone Woofer and Dayton Audio - TD20F-4 - 3/4" Soft Dome Neodymium Tweeter 4 Ohm.

Are they ok for my project? Or i should go for Dayton Audio - ND140- 4 - 5-1/4" Aluminum Cone Midbass Driver 4 Ohm? How about Peerless Fabrikkerne (I) Ltd - TL25AN - Aluminum Dome Tweeter?

Tight on budget, so not considering higher priced tweeters. Peerless Fabrikkerne is Indian brand and read they are not upto standard, not sure though, but goes upto 1.5khz.

Preferring sealed enclosure as small as possible. So dedicating woofer to its duty and FR for high bass and mid. Thats why 3 way is considered. Am i wrong? Thanks in advance.

Hello everybody

After a long time of research, I would like to solicitthe diyaudio community for this question.

I would like to add a volume log potentiometer to my Sanwu TDA7492 + CSR8635 bluetooth board (please find attached a picture of my board).

Indeed, I want to add a volume potentiometer before the TDA7492 amplifier in order to change the volume, no matter the source (in my DIY project, the board is connecting permanently to the aux input and the bluetooth input, and the source is chosen by a manual switch).

I would like to know if it is possible, and where can I add a volume potentiometer to control the volume.

Thank you in advance for your help.

Note : For my project, I work in Mono. I flashed the CSR8635 Bluetooth module to work in Mono only. So I guess I will only use the L channel at the end. So I want to know how to wire a single potentiometer of 22k resistor.

Moving back to the midwest so I'm putting my Allens up for sale. They are working flawlessly but I don't want to try to ship them back to Iowa. I have until the 20th of May to sell these or try to find room on the motor home which is already crowded.

Price for the pair at $1100.00 cash and you pick up here in Casa Grande, AZ

PM me for my phone number if interested. No trades and my price if firm.

Hi, got an amp with BUZ71 mosfets I want to change out from the power supply as some are reading faulty, is there a newer equivalent I can put in and would I need to change gate resistors to suit? the amp is nothing special but interests me so would like to fix it up, it's a Precision Audio "Hot Shots", which is a bit of a joke amp but would like to see it work again!

Mark.

Follow URLs are online:

Acoustech PH-1 and Premium Version PH1-P
https://www.diyaudio.com/forums/solid-state/5265-sutherland-amp-information.html#post51617
post #32 under
Good replacment for BB OPA 2604/604
AcousTech Electronics PH-1 phono preamplifier | Stereophile.com
Vinyl Asylum
http://showroom.acousticsounds…x.cfm?do=electronics_ph1p
https://www.usaudiomart.com/de…d-mc-look/images/1483739/
https://www.canuckaudiomart.co…no-preamp/images/2277196/

Ron Sutherland's 20/20 (Sutherland Engineering)
https://www.youtube.com/watch?v=wIvwQZZd6Iw
https://www.youtube.com/watch?v=pAsxg3NLCX0
https://www.stereophile.com/content/new-preamps-ron-sutherland
https://sutherlandengineering.com/products/2020/
https://www.hifishock.org/gallery/e...lifier/phono-preamplifier/20-20-1-sutherland/
https://www.hifishock.org/gallery/e...plifier/phono-preamplifier/ph3d-1-sutherland/
https://www.stereophile.com/content/sutherland-engineering-2020-phono-preamplifier

Who can upload the schematics of both phono preamps ?

Hi

I have a question on this schematic.
What is the function of the resistor R6 on the output?


Regards Johannes

Hi everyone, I am new to the forum.

Moderation note

Technical question below moved here:

Martin Logan Depth i subwoofer amp board KABOOM!!

Recently got a ML Depth-i Subwoofer for a project. After opening the sub for further trouble shooting, found out the amplifier board is totally fried! Corrosion on the board everywhere! After calling the ML service dept, I had the feeling that they are NOT going to do anything.....no parts, no suggestions..COVID-19 excuses.... So, I am thinking if it is possible to find an internal amp board that is compatible to the sub? I think the power supply is still good? I have no knowledge in circuit stuff and only know how to use the multimeter to check voltage and connectivity🙁😕 Correct me if I am wrong....power supply to amp board to crossover to sub cones? or is it possible to use an external amp to drive the sub? Thanks in advance for all the inputs and suggestions!!🙂

Hello!

I am planning to build a pair of speakers as a gift to my friend for his birthday.

I have built 3 sets of speakers so far, CHR-70 3L sealed, 9L bass reflex and Fane SOVEREIGN 12-250TC 90L sealed.

I am considering smallest 18L Dr. Scott Lindgren design for the CHN-110.
F3 = 46Hz F6 = 39Hz. Paul Carmody says that Classix II has F3=34Hz.

Why am I comparing those two - price level is basically the same and the size is also similar 15L vs 18L. Both are quite easy to build.

My questions are:

1. Classix II has way more bass extension, but uses cheap drivers. Since I don't have experience with large bookshelf speakers I have no idea how different would these two speakers sound. Low and precise bass is always nice, but the mid-range magic and imaging that comes with MarkAudio full-range drivers is the main reason I got hooked in diy audio in the first place 🙂 Could someone with more experience please describe the differences in more detail between those two designs.

2. CHN-110 is rated at 45W nominal and Classix II is rated at 60W. What would be the best bang for the buck amplifier solution? It's either TDA7498 or TPA3116 based Bluetooth amplifiers (both cost around 40 EUR), but the most powerful power supply that is cheap (max 15 EUR) is 24V 5A. Anything with higher ratings - then price jumps considerably (TDA7498 can take 36V). What I've managed to find with google, is that 24V 5A power supply gives me around 38W at 8ohm with TPA3116 based amplifiers. Are any other boards that sound great, cost about the same and give out more power with 24V 5A power supply? Or is this power supply my limit - 38W at 8 ohm and it doesn't matter what board I use?

Thank you for all the help!

Hi friends

Oftentimes, I just can't solder around.

So I started to build a database (ninox) where I try to gather and connect as much information as possible as fine-grained as possible, like

• who wrote (what piece)
• who played (what instrument)
• who contributed (on which track)
• who recorded it
• who published it
• what do I or other family member like
  

You get the picture. Kind of a clone of discogs, merged with my iTunes-library or something like that, so that I can dig out specific informations from the collection...

Of course, this task barely has a boundary, and so I'm quite overwhelmed of its complexity. I would like to find solutions on both the technical (database-design) level as well as the logical level (where to best hook attributes like "authorship, contribution, role" etc.)...

Is there a place where such issues are discussed?
Could this be the place?

Thank you, enjoy sunday!
david

(context:
I listen to music more than not, and try to build knowledge about it.

trying to set up a sort of a catalogue of my music-library, which consists of a inherited collection of classical records (~1500 vinyls), and there's some records in the world of pop/jazz/etc. (~300 vinyls). Plus a huge collection of digital files (~500 ripped CD's, + ~300 Albums purchased through bleep + bandcamp)
)

Hi guys, the soft start lately has been clicking nuts of my power amp. I swapped out for new caps ,IC- cd 4060 and new BC 337 that drive the relay but the problem persistent. Please any tips for trouble shooting?.

Quan

I decided to make my amps myself rather than buying brand new ones.
I left on a base of L25D (IRS2092 + IRFB4020PBF) from JLM.
The set will be powered by + - 75V by a custom toroidal transformer , a power supply card and protection HPs.



After modeling to choose the case:


I started manufacturing:

I’d like to know your opinion. By the time making the speaker, shall I use manufacturer’s provided information or measure it by myself? The information such as frequency response, impedance curve, inductance, etc. I think that the data from manufacturer probably are more correct than self-measuring because they may use the more precise equipments and methods in measurement. However, as someone says that since it was a commercial, the spec might be fabricated to have more beauty, and probably just a sample from a lot. So I thought would it be better to measure with our moderate precision equipments and method ourselves. But that also the question for the purpose of spec from manufacturer. Thanks in advance

I recently picked up a used ARCAM DiVA A75 integrated (50WPC) for a song because it had a problem. Seller stated the amp would not go out of protection mode on turn on, relay would just keep clicking. I contacted ARCAM about this and to my surprise got a response same day. Probable cause according to ARCAM was cold solder joints on the output transistors. Sure enough that was the problem. I re-soldered them and that particular problem was solved.

Which brings me to the purpose of this post. Right off the bat this amp sounds like s**t...boring, lifeless and veiled. I've owned several ARCAM integrateds including the Alpha 9, which I'm currently using, the Alpha 10, A65+ and the A70. Everyone's aural memory is short but I do remember the A65+ (40WPC) sounding better than the A75. To my ears the Alpha 9 is the best sounding of the lot and the A75 the worst. ARCAM also made a A75+ which I haven't heard. I contacted ARCAM three times asking what the difference between the A75 and the A75+ was to no avail. Does anyone have any idea what the difference is? They obviously tweaked the plus version cause the other sounded like crap.

For those of you who don't know the Alpha and Delta series of amps used MOSFET outputs and the DiVA range, which followed the Alpha's, use bi-polar outputs. The A75 uses for the pre amp section one BurrBrown OPA2134 DIP op-amp and the phono stage uses one Philips NE5532 DIP op-amp. Are there any serious tweakers out there that can help to make this amp sound better?

Hi everyone, I am new to the forum. Recently got a ML Depth-i Subwoofer for a project. After opening the sub for further trouble shooting, found out the amplifier board is totally fried! Corrosion on the board everywhere! After calling the ML service dept, I had the feeling that they are NOT going to do anything.....no parts, no suggestions..COVID-19 excuses.... So, I am thinking if it is possible to find an internal amp board that is compatible to the sub? I think the power supply is still good? I have no knowledge in circuit stuff and only know how to use the multimeter to check voltage and connectivity🙁😕 Correct me if I am wrong....power supply to amp board to crossover to sub cones? or is it possible to use an external amp to drive the sub? Thanks in advance for all the inputs and suggestions!!🙂

Hi everyone,

I'm repairing an outlaw 7125. This amplifier is an AB class with only one potentiometer to adjust bias. Nothing to adjust dc offset.

Anyway i have 7v and 3v on 2 channel. Do you know what is causing this ? I'm comparing a working and a bad channel and i found nothing. Already replace all capacitors. Test every transistors and resistors. I'm not able to find the source of this issue.

I tried to have the schematic or service manual but it's not available anywhere. I wrote to company and not providing any schematic.

So i did it. But again i dont find the problem. I will need help on this one.

I read somewhere that some model without dc offset adjustment, transistor need to be matched. Is it possible ti have good transistor but not matching anymore ?


This is my schematic:
Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

Thank you for your help.

Looking for excellent discrete class A Balanced input to Balanced Output Preamp that will drive a class A amp with input impedance of 2k2. Any ideas?
Thx
E

I am working on a Technics SU-50A. The Right channel can be perfectly set to 25mV of bias and close to 0mV of DC offset. The Left channel's DC offset is about 155mV when RV17 is turned all the way. It's bias is ok. I have checked the differential pairs, TR17/19 and TR21/23. They seem to match well.

Can someone educate me how dialing RV17 can affect the DC offset? What should I do to bring the DC offset down?

Its been 7 years now that I have been running a 5 channel memphis amp that Perry Babin walked me through the steps and helped me repair it and its still going strong.

Hello guys, at some time i started to think about getting a projector but they are very expensive , and cheap ones are very bad. i am thinking now that i wont loose much by making projector myself instead of buying cheap one.
Sad that I discovered this forum after I ordered all parts
so i have lg g3 phone ips screen with 1440 x 2560 pixels resolution 5,5 inch in size i am going to put it in between these lenses High Quality 1 Pair DIY Universal 7 Inch Fresnel Lens 0.1mm Spacing For HD Projector FPV Goggles Headset-in Parts & Accessories from Toys & Hobbies on Aliexpress.com | Alibaba Group and problem is i have no idea how to choose lens for image projection , in front fresnel lens is 170 mm for focus so my current choice is lens witch claims to be 180 mm focal length
Factory sale! LED Projector DIY Lens Focal Length f=180mm DQPL F180 Projection Lens for 3 7 inches Projectors LCD-in Projector Accessories from Consumer Electronics on Aliexpress.com | Alibaba Group ? ,So my problem is i have no idea how projection lens parameters efects final image and want fresnel lens to fit the projection lense , maybe someone has any sugestions? I have space between projector and wall from 4-5 meters, is my 180 lens suitable for my setup or where is a better option?

At the moment I am waiting for parts to arrive
8.31.17
Fresnel lens and power supply has already arrived and i have found some coolers,

Hi,

I just played around with this $8 loudness volume control from China. It seems to have killed my bass, treble and made it dull. Do you think it's a good idea to add a JFET buffer after the pot ?

Japan AIKO 100K Equal Loudness Volume Control Dual Potentiometer Adapter Board | eBay

Thanks much.

Hello everyone,

I have come across some strange behaviour of the IRS2092 class D driver IC that I have not seen reported before. In the documentation the only damage warning that I can find relates to Vss falling lower than the COM (B-) supply:

VSS Negative Bias Clamping
An excessive negative Vss voltage with respect to
COM could damage the IRS2092(S). VSS can go
below COM when a negative supply is missing in a
dual supply configuration. To protect the IC from this
possibility, a diode is recommended for clamping
potential negative biases to VSS. A standard
recovery diode with a current rating of 1A such as
the 1N4002 is sufficient for this purpose.

I have an ES1D diode in my design as per the above. My current project is based around the IRAUDAMP9 reference design, with the following changes:

Gate resistors 10r instead of 4r7, reverse turn-off diodes across gate resistors, and separate power supplies for +/- 75V, Vaa, Vss, and Vcc (from individual transformer windings, rectifiers, and filter capacitors). Vcc is created with a 20V supply feeding a 7812 regulator, referenced to B-. I have reverse polarity protection diodes between B- and the VCC supply (at the input side of the 7812), B- to GND, and GND to B+. Each of the five power supplies has a protection fuse. The amplifier works perfectly with low noise and distortion, switching characteristics are all good, and I have no problems using it for the past few weeks. Yesterday I encountered something that I cannot explain: I was performing some measurements and accidentally powered up the amplifier without the fuse installed for the Vcc power supply. Obviously the amplifier did not start and there was no fanfare. I switched off the main power switch, waited for all the supplies to discharge, and then reinstalled the Vcc supply fuse. Bringing up the amplifier using a variac, the B+ and B- fuses quickly blew...they have never blown before. Upon inspecting the amplifier I found a ~200 ohm short between B- and system GND. I removed the IRS2092 IC and found the short was now gone. I double checked all of the surrounding components, including the BJT totem poles and the MOSFETS. Nothing else was found to be damaged, so I installed a new IRS2092, slowly brought up the amplifier, and it is again working perfectly. I decided to do an experiment to test the UVLO for Vcc and see if I could duplicate the failure...this is supposed to stop switching if Vcc falls below approximately 8V. I replaced the Vcc fuse with a high current switch, powered up the amplifier until it reached normal operation, switching present, etc., and then flipped the switch, disconnecting the 20V Vcc feed supply. Switching stopped immediately once Vcc reached just over 8V relative to B-. So far so good. I then switched off the main power switch, with the supply to the Vcc regulator still disconnected (simulating a blown Vcc supply fuse) and again the IRS2092 was damaged in exactly the same way. Replacing it got the amp working properly again. One thing to note is that on turn off the Vaa and Vss supplies (and Vcc, when it is connected) discharge much faster than B+/B-. Has anyone encountered this or any other failure conditions? Can anyone recommend what I might look at or implement to prevent this failure mode? I suppose I could just eliminate the fuse from the Vcc supply, but I like to have fusing when testing and measuring a new design...for obvious reasons.

Thanks!

Is there a new/used distortion analyzer for <$500 out there?

I hate to pay for a used distortion analyzer/shipping costs that the seller can't say is working or not because they don't know how to test.

Any recommendations would be appreciated.

Hi All,

Hoping to get some feedback on the crossover for a project of mine. I am crossing over a SEAS 27TDFC H1189 to a TB W5-1685. I have developed a 2nd order high-pass/low-pass crossover (as I feel the drivers lend themselves well to 2nd order networks) with the high-pass at 2080Hz and the low-pass to the TB at 3360Hz.

I initially started with both being at 2300Hz but landed on these values after some tweaking on VituixCAD (I also added a 4ohm resistor to the SEAS and wired it in reversed phase to avoid a large trough in the frequency response).

Just hoping to have some feedback as this is a first for me. I also question my calculations for the low pass filter as the 3360Hz doesn't seem to correlate on the graph with the blue line for the TB W5-1685. Using equation 1/(2pi√(L*C)).

Graphs, circuit, and datasheets attached.

Thanks!

Hi,

I want to add a current overload protection to a regulated high voltage power supply.

The design is somewhat similar to the schematic attached (but with zener stabilization), using a power MOSFET. The default output voltage is 600 VDC. The default current will be around 400 mA (fixed current, true class A amplifier).

How should I calculate the resistor value for the BC337 to get a current protection for 450 mA or 500 mA?

Regards, Gerrit

It is always convenient to design a new build around an IEC standard power adaptor, and generally people opt for the C13/C14 type, which is similar to (but not the same as) a 'kettle cord'.

There is another polarised type with earth connector, the C5/C6, aka 'Cloverleaf' or 'Mickey Mouse' connector. It is rated to 2.5A, 7A in the US, so should be meaty enough for any amp with a 300VA power transformer, with plenty of margin for safety.

I'd like to retrofit some Quad II's with earthed power leads, and there is just insufficient room in the old voltage selector window for the C13/C14 type. Rather than hack the old chassis, I could fit a C5/C6 type with no surgery required.

To be on the safe side, I was wondering if there is there any safety reason not to do this?

Hi All

Have anyone ever tried one of these opamps for sound?

Regards Vitreus

Are there any opamps that are particularly suited as tape output buffers? Or would an ad797 work well?

I'm searching Farnell for 22AWG stranded wire used for heaters and also some other connections in line level stages. Typical requirement is 6V/600mA, never had problems with wires similar to Tasker C111.
Shops are closed so i have to order something without seeing and touching it, the problem is i spent 2 hours trying to calculate or find diameter of 1 external core from multicore cable. It is pretty clear here, 1,8mm dia for 22AWG core.
https://www.tme.eu/Document/e9b173cef568e662b651ce08f5ffc9af/TAS-C106.pdf
Online shop where i want to buy this wire also carry some other things, if i make sure wire is how i need it i can avoid 2 shippings. Datasheet shows 0,76mm conductor dia and 1,27mm insulation diameter:
http://www.farnell.com/datasheets/1...2Yb963grkGG4pRW2sij6WKAS5e0y6CchoCOtIQAvD_BwE
http://www.farnell.com/datasheets/1...2Yb963grkGG4pRW2sij6WKAS5e0y6CchoCOtIQAvD_BwE

Do i just calculate 1,27+0,76 =2,01mm to get diameter of 1 core with insulation, or am i wrong about it?

Hey all,

Quick question - I have a phono preamp, with a c3g on the output stage.
Currently, it has a 470uf cap for the bypass cap, but was wondering if I can replace it with a 1000uf cap?

I'm planning a voice coil for a 12'' subwoofer I'm going to build, and I already have the magnet and the frame.

I made a test coil to measure the force factor, and from measuring it's dimensions (plus assuming it uses some common materials) I created this model in FEMM:





From using those materials the force factor fitted right away.

You can see I've already added a voice coil to the model.

My doubt is the following: I planned the coil to be 27 mm tall so it could have a 10 mm Xmax. But, like that, when being fully "down" (like in the picture), the bottom of the coil itself would be 6 mm from the bottom (from hitting that curved part of the bottom).

Considering that I need a bit of former left below the coil (to avoid it from bottomming out when going "up"), this leaves me with very little window to anything. It could easily hit the bottom when going down.

So what you think is the wiser to do?

What you think it's a safe Xmax to avoid the chance of mechanical damage?

Note I'm planning to use this sub in a transmission line enclosure, and I'm planning to use it with a 150 W RMS class D amplifier. I'm not yet sure of how much excursion I'm going to need and how much control the enclosure will offer, but I'm following the parameters of known 12'' subs of similar power rating.

Frankly, I keep building projects that require way too many holes thus the chassis are always tedious to drill by hand. Is there a common internet outlet for custom chassis that is used on diyaudio?

I got a quote from protocase for a tube guitar amp chassis but at $600 a chassis it's a bit steep.

So we know that with diaphragms undergoing pistonic movement, the radiation pattern transitions from spherical/hemispherical to something that looks more like a beam as the frequency increases. The reason for this is because as the wavelength shortens, the sound waves produced at different areas of the diaphragm start to destructively interfere (combine out of phase) at the listening/measuring point, instead of constructively as they would at longer wavelengths.

What if we reduced or blocked the output from one part of the piston (in this case a dome tweeter) so that only a smaller portion would radiate to the point of interest? In theory, this would increase the frequency at which the dome would start to beam. One way to do this would be to put a thick sheet of felt over the dome, almost in contact with it, but with a small circular hole right over the tip of the dome. The portion of the dome visible through the hole would radiate as normal, as long as the listening/measuring angle was not occluded by the periphery of the hole, but all the other parts of the dome would not be able to contribute their sound energy.

So, this should work to improve off-axis response at high frequencies, but we've done nothing but turn one dome tweeter into a smaller dome tweeter, which is hardly better than selecting a smaller dome tweeter to begin with. The major downside we have now, though, is that the surface area has been significantly reduced which in turn reduces the peak displacement of the dome. This means that we now have less clean output at the low end of the dome's passband. How to get around this? Use a thinner sheet of felt, so that low frequencies (which constructively interfere) are less attenuated, while high frequencies (which generally interfere destructively) are more attenuated. One can imagine that there is a sweet spot, or sweet "range" of thicknesses that may be suitable for this application.

The end result is a dome tweeter that has perhaps a negligible drop in sensitivity at the low end of the passband, a slight drop in sensitivity in the midrange, and a significant drop in sensitivity at the top end of the passband, but with a significantly improved off-axis dispersion at the top. Easily solved with EQ, and the nice thing is, the tweeter is unlikely to thermally overload under normal SPLs since the spectral distribution of energy in almost all kinds of music drops with increasing frequency above 300-500 Hz. Off-axis dispersion is more important in near- and mid-field listening, which comparatively requires less power as well. Excursion is a moot point since the the whole point is to select a felt thickness that hardly attenuates the frequencies where dome displacement is critical.

Unfortunately, all of the above is purely my conjecture... I would love for anyone to put this to the test. I'll even pay for the felt!

First off I have to say that all my knowledge base is in building tube gear, and my solid state knowledge is pretty basic.

I need a gain of about x2 or x3 between the output of my AK4490 DAC with NE5532 output, and my 300b SE two stage amp. Obviously I want the cleanest most transparent solution possible and I'm open to a solid state device, rather than a transformer.

I have no knowledge how to implement this, so I'd be extremely grateful if you could point me in the direction of what I need. I can build circuits and PSUs, though I haven't worked with SMDs. Thank you in advance.

So I just purchased a pair of Tang Band W8-1808 full range driver and started thinking about what I could do with them.

Currently I have a few pairs of unity / synergy horns (300-20k hz) together with some simple and plain open baffle bass speakers. Ofcourse not the best combo since the horns have a very high efficiency and the bass does not.

I like the open baffle / baffle less sound so I want to go all the way with that for this new project and because my new work space (which will also be the listening room) is way smaller than first, I want some smaller speakers.

I am really fond of speakers like the Kyron Audio Kronos or the ones from Reflector Audio.

I want to use my bass drivers that I already have since I like how they sound and perform, these are FaitalPRO 15pr-400. I made a design where both drivers are as close together as possible, thinking of a crossover around 120hz or so to give the full rangers some relief at the bottom end.

BUT now the BIG question, what will happen with this set up? I really dig the look and everything, but will the 15" movement closely behind the full range driver cause distortion? It is firing straight into it, ofcourse the full ranger will move approx. the same but has a cutoff where the FaitalPRO steps in.

Total disaster?? or will this be ok to try?

The frame connecting the two will be laser cut from 5mm stainless steel. As for the legs I have to figure out a nice way that is at a reasonable price...

EKIO is a Loudspeaker Management Application. It lets you customize the sound of your loudspeaker system so that it sounds and performs optimally. The app allows you to easily create a crossover for your full-range speakers. It lets you integrate a subwoofer and equalize your system.

It features:

• Real time audio processing
• Interactive EQ display
• Crossover configuration
• Parametric EQ
• Driver alignment delays
• Flexible routing
• Drivers measurement import
• Unlimited I/O
• 64 bits processing, 44.1 to 192kHz
• Optimized for low CPU usage and low latency

The FREE version is limited to two inputs and four outputs.

We publish today EKIO v1.0.3 which contains a few bug fixes.

To learn more about EKIO, visit our website : www.lupisoft.com/ekio

Regards,
Lupisoft

I'm in the process now of fabricating a project that uses transformer coupling at the input, 600 to 10K line transformer. I would like to get Sowters but for the two models I'm looking at the price nearly doubles one vs the other. The project I'm doing is on another post here, basically a computer desk amp where I might have 6-8 different sources plugged in at once sharing the ground. So I want a transformer input to alleviate ground loops and get some gain.

Can someone more familiar with input transformers tell me what I am getting for the extra money between these two models? I understand that quality vs price is never linear, but I have no problem spending for the more expensive model if the sonic reward is measurably greater.

USD $74

https://www.sowter.co.uk/pdf/8540.pdf

vs...

USD $138

SOWTER TYPE 3575 TRANSFORMER

Here are some of the advantages I've garnered so far for spending more on the 9063 model:

1) I can have a balanced input source as well as all my RCA sources.
2) More headroom and inductance, all the sources will be from op-amps (CD, DAC, Random headphone output of a phone, Bluetooth adapter, my DJ fader, etc). Some sources may be "hotter" than others.
3) More bandwidth
4) Better distortion
5) Having separate secondaries offers more parallel/series design choices for wiring it up.

What do you think? Should I spring for the $138 model? We only live once.

I bought one of these SMSL M300 dacs, and it came with a split dac cable
(one side for power and the other for data).

Now, what's the point of that if you're going to plug both ends in a PC? lol.

Hi All,
We've been cooped up in our house here for weeks due to the covid-19 thing so I figured it was time to do something about some old speaker cabinets I have. After doing some initial internet research, I've come to the conclusion that the only way I'm going to get satisfactory results is with a little help before I jump in.

Please take pity on this noob and thanks in advance for any direction you can provide.