Hi - I just received the 2 Dissipante 3U cases I ordered and I don't see assembly instructions, just a bag of screws and a exploded view picture of a generic case where I can't see clearly which screws are which.. Are there a set of instructions online? I couldn't find any on the modushop or diyaudio store sites..

What a wonderful resource this forum is!

Over the years I've learned and forgotten and then re-learned LTspice several times. This time around, I'm writing up my learnings in blog posts, so that years from now when I've forgotten it all again, at least I'll have a reference 😀

Here's a first post: a basic zener voltage regulator Basic Zener diode voltage regulator * GitHub

Cheers!

With so many cheap Chinese amps available I can't have been the only one tempted to buy something ready made. So rather than completely hi-jack a thread about building amps I thought a new one about what people have bought or are thinking about buying would be good. including pre assembled PCB.

I've bought but it hasn't been delivered yet an Amp claiming to be a 12 watt per channel JLH 1969 Class A amp in two cases one for power supply one for the amp. All is not quite as advertised though - as has since been pointed out to me the heat sink is too small for 12watt class A amp. A closer look at some of the photos shows a pair of OP Amp chips next to the volume pot View attachment JRC5532-JRC.pdf

Here's the Amp
LP Spirit Pure Class A 1969 Amplifier Computer Desktop Mini Merge Split Type HIFI Audio Power Amp|audio power|power ampa class amplifier - AliExpress

We've all seem tube amp hybrids - this looks more like a 1969 JLH hybrid now. It might even deliver the claimed 12 watt per channel what do you think?

I have watched this several times now and I can't really get over how good it is...all subjective of course.

It sounds crystal clear and the picture is also very good if that bothers you. I find playing good music through a good system that includes a good size high quality picture really gives you an immersive experience....i damn near shed a tear!

SOHN - Live with the Metropole Orkest - Full Concert - YouTube

When i power the amp up this resistor starts smoking. If i pull the driver card it doesn't happen. Ive replaced all the transistors and the irs21844s chips.

The OT I'm using has a center-tapped secondary. In its original application, it was grounded at the CT. Is there any reason to choose that over grounding at one end? It would just change the ground reference, which doesn't matter to the speaker, right?

rega RR125

Ok, here it goes: does anyone has any experience with Rega drivers or their speakers (like Kyte, RS1 and so on...). I had some decade ago their small Kyte speakers on stands and like the big, spacious soundstage with realistic timbre and good vocals. Only big speaker offered me later better performance.
I had some fostex (fe206e in front horn and fe103 but they seem to make sound too monitor like and not so lifelike). I admit I forgot the 103 performance but remember liking them somehow with smaller pieces of music (vocals, chamber), but did not like their smallish power and dynamics. The sound wasn´t as big as with Kytes either.
Now, I got some old JR149 speakers that have the bass 5" unit missing but the tweeter is there. They look promising as they are of oval aluminium shape and will use them as my working speakers. That means 1m max. away and fed by pc with DAC and amp (still deciding to buy either a smaller tube amp or some chip T-amp-never heard them and want to try one, now I have quite good old Sony reciever, the STR6046 model).
My question is - this driver RR125 from Rega or some new Fostex like FF 125 WK full range.
There is also possibility that I replace the tweeter and put some planar ribbon there to cover above 7khz if the RR125 driver doesn´t go so high as FR (something like jr149 , below).

What scares me is the aluminium dustcap on the FF125 WK. I usually detect metal membranes immediately and my ears are fixed on paper sound as an ok element. Even big planars don´t play for me. Khm, ribbon tweeter... maybe it will iritate me also 😉
I do listen to large orchestral music and right now I have some Monacor sph68x drivers (spectrumaudio) installed in and they can cope with that quite ok but their resolution is not on par with regas and fostex.

Any suggestions about different driver or maybe just on sound of fostex ff125wk, regarding the alu dustcap.

thank you in advance

I read this:
thread
and it seems that ff125wk is quite liked.

!!
T

Hello!

Can I use two of this and make a bridge conection? ZHITING TDA7293 Mono Amplificador de Potencia de Audio Digital monocanal Junta AC 12-32V 100W: Amazon.es: Electronica

I can get it very cheap and have it with the advantages of prime 😛😀😀😀

Hello experts in speaker measurements.


I glanced over at the Stereophile measurements for the Gobel HE Divin Marquis speaker and ran into a very interesting chart. Besides being commendably flat (for a commercial speaker), look at the regularity of the humps and valleys between 1 kHz and 10kHz:





Is this from the (what I assume is) a Beyma AMT or is it attributable to edge diffraction, or something else?


Best,


Erik

I have a ScanSpeak Discovery 30W/0-00 12" Passive Radiator for sale. It matches the 30w/4558t-12-Subwoofer. I bought it to use in my car with the 4558 but it did not work out in the car environment. The passive has less than 1 hour on it but I did manage to poke a small hole in the surround while removing it from the enclosure, I've repaired this and it is hardly noticeable. The passive also has a white gasket which I will remove or leave on at the buyers request. It will be shipped in the original box at buyers expense.

$60. OBO

Here is a link to my subwoofer thread:

ScanSpeak 30W/4558T and 30W/0-00 sub failure.


ScanSpeak Discovery 30W/0-00 12" Subwoofer Passive Radiator

ScanSpeak Discovery 30W/4558T 12" Subwoofer

Hi all,

I build a reset circuit similar to the attached schematic which i found in the internet.
The only thing i changed is resistor to 100k and the 0.1uf cap to 47uf to have a delay of around 5 secs. The output 3 is triggering a BC557 transistor instead of the 74ls05. The goal is to set a reset line once to 0v after 5secs for a short time and release it after.

It seems to work for triggering the transistor and setting the line to 0.6v after 5secs, but the output stays high. How can i change the circuit to set the output 3 of the ne555 back to 0 after 0.5secs?

Thanks

Should I use Nichicon KL, KG, or Panasonic FM for the capacitors? Should I use LT1468 or AD797ANZ for U1 and U2 in the oscillator? Should I replace both U1 and U2? If I use the AD797, which compensation components do
I remove? Which ones do I remove if I use the LT1468?

Here is my parts list so far:

Pots:
(2) 3339H-1-202LF 4 turn 2k
51SAD-U25-A15L 1 turn 10k

IC:
AD797ANZ

Caps:
see attached

Hello People

Picked up an old school dac, well the first separate dac ever made no less ( from my research... )

Well it dont work 😉 It powers up. Mutes with no input ( has a display to show ) and unmutes and gets a sample rate ( again light comes on , well 32k and 48k do bulb gone me thinks in 44.1 but makes no output regardless so pretty sure its just dead bulb there ) Relays open and close on mute and unmute on headphone and line out.

So I know its getting power to the analogue section as psu measures good and there is power in some places around the analogue section. Digital must be running somewhat as it see's the signal ( various sources such as cdp and computer soundcard )

There is no audio on the headphone or fixed or variable line out. I guess I need to measure if there is any audio in the signal chain. Not sure If I can do this without a scope...... I guess I should be able to measure some voltage somewhere with a test tone running on the input. Board layout is clear and I have the circuit diagram....


Any advice on where to go next would be much appreciated. I know the financial gain might not be worth it but its a challange ....

Dave

I spend all day setting up a Pi Zero W with shairport-sync and bruteFIR. It works fine using the alsa loopback method, but I still have to start bruteFIR manually. This is my unit file, is there anything wrong?

Hi, Checking a Banda Viking 15,000. I'm getting 150 volts across the speaker output. Meter positive on the speaker positive. Negative on the negative. No shorted outputs. Looks like this amp only has a -rail.

Hi All,
Recently I bought a TEAC VRDS-10 and using it as a transport. I am extremely happy with the result of this transport. However I also now have an option to buy a TEAC VRDS 25X. It will cost me a lot more...around $1500. That is thrice the cost I paid for the VRDS-10. But I have heard lot of good things about this player so I thought I may want to give it a try. Also the 25X is a more recent model and is in mint condition so it would hopefully give me longer service.

But But But, the milllion dollar question is.......how much better is the 25X as a TRANSPORT compared to the VRDS-10 ??

I know its transport is similar to the VRDS-10 but has some additional mods...now with all that will it be a significant upgrade from the VRDS-10 ? Please do look at the price factor also. I do not want to just go for it for the sake having a newer better model unless it really takes the whole game to a higher level.

I was initially thinking of using the VRDS-10 for a couple of years and then as I save some money, I would have tried to go for a newer Esoteric model. But this VRDS 25X is a bit tempting so I thought I would ask people who have more hand on with these machines and only then take a call.

Please suggest asap because I have to take this call soon.

Hi,

Have ordered 4 boards from the diyaudio store to make a pair of Amp camp amps and was wondering where the UK people buy the heat sinks from? The rest will be ordered from digikey uk.

Thanks,Rob.

Assume I design a simple 4th order boom box, single driver, and single port. Assume the driver is 10 inch sub, calculated box volume is .75 ft^3. I am also very meticulous in my measurements. I also take into consideration the port volume and the volume of the back of the woofer in the over all box volume. After construction is complete, I take the time accurately measure the compliance ratio of the box with an impedance curve in its sealed state (port sealed off) and in its vented state. It turns out from (alpha=Vas/Vb) that the box volume is different from what I initially designed and therefore the tuning frequency is different. Now I want to adjust the port length to adjust the tuning frequency of the enclosure to what I thought it was going to be to start with. At the same time by extending the port the box volume increases (or vise versa). My question is. When I calculate the new port length do I add the additional port volume to the port length equation? I don’t know what that is until I calculate the port length from that equation. Any thoughts. Even in the initial design you can’t accommodate for the added box volume from the port because you can’t calculate the port length with out knowing the additional port volume. You can’t get the additional port length because you don’t know the final box volume.

hi all
ive juse aquired a sony das 702es dac.
the trouble is it has some problems in the form of noise.
its fine when first switched on,then after about a hour and 40 minutes it develops a noise similar to static from a radio on the left channel when playing music,if i stop the music playback then the static stops through the left channel but is replaced by a loudish wooshing noise through both channels this time??
anyone have any ideas,clues where to start?,i was going to recap the dac but that will cost quite abit,i dont mind doing it as the breif listern i had of it seemed quite decent,however i dont want to invest a small fortune if its a problem i cant sort out,also opinions regarding the quality of this dac soundwise would also be appricated compared to todays offerings for those that have owned or heard them.
many thanks in advance for any advice/help.
all the best
smithie.

Looking to make a second amp, this time with some higher powered modules.



I am thinking of the Dissipante case, but was wondering what purpose/how well the heat sinks work if I am mounting everything to the base plate add-on?


I doubt the base plate transfers heat effectively to the actual chassis for heat dissipation, correct?

I live just north of London and am hoping to find someone not too far away who could help me design a surface exciter mount.
Any links would be greatly appreciated.

Hi,

Just a little post to introduce myself.

I'm 28 and I live in Belgium, I'm a really audio passionate, I build cabs for 8 years now, at the beginning based on internet plan but I started create mine own design 2 years ago and now I'm totally addict.

At the beginning of the pandemic I couldn't work so I go deeper and deeper into my knowledge, cad program and simulation software like akabak2 or 3. Now I'm doing that all the day every days 🙂

See ya

Sale:
6С33С-В usual — 140 pcs. for $20 ea.
6C33C-B — with two bumps on the top — 30 pcs. for $20 ea.
6S33S Svetlana brand - 2 pcs. for $30 ea.
Sockets for 6S33S – 48 pcs. for $10 ea.,
Sockets for 6S33S used – 4 pcs. for $8 ea

The Sounds of LS 3/5A Vol 2
$24.00





1. Mozart, arr. Savall: Alla turca. Allegretto

2. Bocini: Ballata No.3

3. Gershwin: Fascinating Rhythm

4. Vivaldi: L'Inverno (Winter) – Allegro

5. Handel: Lascia ch’io pianga (from Rinaldo)

6. Monti: Czadas

7. Lowe/ Turk/ Mike, arr. Mealey :Medley: Teddy Bear/ Are You Lonely Tonight/ Treat Me Nice

8. La Luze De Oro (musica Philippe Eidel/ poesia Biagio Marin)

9. Falla: Introducciò y danza del Corregidor

10. You Belong to Me

11. Bizet: L’Arlésienne, Suite No. 2, Op. 23: III. Menuet

12. Sur ce chemin (On This Path)

13. Farbay di Teg (Those Were The Days)

After ages of dithering, I finally pulled the trigger on Aleph J boards and two Universal PS boards from the DiyAudio store. I am now putting together the BOM for the project. With respect to the power supply, I have a couple of questions before I can order the parts. (If this post should be in the Aleph J build thread, please let me know.)

First, I know that for a stereo build 8 caps of 15,000 uF each are recommended (for a total of 60K per rail or 120K total). I also know that since each psu will only power one channel, I can reduce the capacitance somewhat. I cannot, however, find anything that says precisely how much. Is half appropriate? Is there any advantage to having greater capacitance? I could use 120K in each channel if that would be advantageous. I recall reading somewhere that too much capacitance in a ps capacitor bank can be counter productive. Can someone help me out on this? I tried Duncan, but that appears to be a little over my head at the moment.

Second, I have discussed in other threads that I have 4 ohm speakers and thus would be creating extra heat to no good effect if I run the amp at +/-24 volts (unless I increase the bias beyond the capacity of my heat sink). (Incidentally, I will be using two DiyStore 4U 300 mm heatsinks, one on each monoblock.) I would like to aim for +/-19-20 volts. Would a 15-0-15 volt transformer work for that? Would I be better off using the typically recommended 18-0-18 transformer and then adding some resistors to reduce the voltage a bit?

Thanks for any help anyone has to offer.

Jazzzman

I live just north of London and am hoping to find someone locally to help me design and build the best mount for a surface exciter.
Any suggestions of people would be greatly appreciated.

Call me crazy but .... Would you see any issue with machining the copper off the back of the pcb with a cnc wood router? One could draw the circuit in their cad software and then "engrave" the unwanted copper away and drill the holes to feed your component leads thru? It would work for simple circuits, or if there is plenty of real estate available, for larger projects. Theoretically, it could be quicker and easier to assemble and solder the board than to do point to point wiring.

No nasty chemicals, or photoresist, or ....

Dear Forum,

I assume that my tube's gotten out, as out of nothing I heard a hum getting louder from my QUADs right channel.
I immediately turned off my amplifier. Checked the biaset's 1,56, whereas after turning on the amp, the left side stated 1,56 correctly after about 1 min, but the faulty right channel didn't stop at 1,56 but started to rise uncontrable, and around 3,00V, the 'faulty' tube's plate started to glow.

What do you think could be the problem? A friend of mine advised me to oversolder all the legs of the tube, that it could be some kind of miscontact.

Anyway, I am planning to swap all the four power tubes, so ordering a quad of el34s, but I have no idea which four should I buy.
I read pros and cons about the Russian Mullards, JJs and other manufacturers products. I have no coverage now for NOS solutions.

My question is that if you have any requirements, experience with these new EL 34's, and could suggest a manufacturer or a good NOS cost/performance ratio set for me.

Thank you for your help in advance!

Hi All

Just giving a Musicl Fidelity F16 a clean u and renewing main caps as they are dry as a bone(never heard a capacitor rattle before)

Looked at rectifier and noticed no caps across diodes to absorb switching noise but Philips orange drop caps wired up like this



Have seen caps across ac inputs before but never ac to ground

Anyone any ideas why its like this?

Ta for any info

John

I have just bought a Leak 2001 Transcription turntable which I would like to do up. The suspension is kind of unique as it uses 3 silicone fluid filled balloons and 3 rubber grommets (thick rubber rings). The 3 balloons look okay but I am replacing them with KAB Sorbothane pods.

However I am still looking for new mounting hole grommets. Does anyone have an idea where to buy those? The rubber of the originals is kind of soft.

Hi all, sorry if I'm in the wrong part of the forums.. This is my first post and I'm not familiar with this site...

I'm having some weird issues with my mixer and what wondering if I could get some help diagnosing the problem. Everything works but I have to turn up the trim all the way up on channels 1-4 to get the green trim light to light up and also causes the red clip light to light up...
Channel 5-6 Instrument/Mic (Hi/z) I have to turn the trim all the way down and the trim light still comes on with the red clip light.
I haven't used my amp in months due to me having surgery but I know something is not right.
Any Ideas?

I am trying to time align a horn with a woofer, and I get about equal frequency response from two different setups. I cant decide which one looks best.

From the attached spectrograms, which one would you choose?

For over 20 years I have had a stereo pair of Peerless SWR 308 / 830500 drivers, each in a 97 liter bass reflex enclosure tuned to 19 Hz. These have proved to be as perfect as I could have hoped for, but unfortunately these have been discontinued as well as Peerless XLS-12.

Considering a similar setup, with a less than 100 liters reflex box tuned to 19 Hz, which of the current subwoofers would give the highest SPL [dB]/W/m, with a quite flat amplitude response, between 20 to 30 Hz? *)

Quickly simulating on-line with www.micka.de ( Vb = 97 l, dia = 10 cm, len = 59.7 cm, Ql = 5, temp = 20*C ) could find at least the following:

Discontinued:
Peerless SWR 308 / 830500 ~82.0 dB/W/m, Xmax 12.5 mm
Peerless XLS-12 / P830500 ~82.0 dB/W/m, Xmax 12.5 mm
Current:
Dayton Audio RSS315HO-44 ~81.5 dB/W/m, Xmax 14.0 mm
FAITAL PRO 12HP1060 ~80.5 db/W/m, Xmax 12.0 mm
SB Acoustics SB34SWPL76-4 ~82.0 dB/W/m, Xmax 15.0 mm
Scan-Speak 23W/4557T00 ~81.5 dB/W/m, Xmax 13.0 mm
Scan-Speak 28W/4878T00 ~81.5 dB/W/m, Xmax 14.0 mm

From these, the SB Acoustics driver looks the most interesting on paper. But, an advice or sharing your good experiences with these or other reasonable drivers would be much appreciated.


EDIT: *) Due the appearance of a frequency response plot, term Extended Bass Shelf (EBS) alignment has been sometimes used.

Hi,

I am encouraging myself in to DIY project 3way floorstander. There few interesting plans available and after searching I found Satorique 4 floorstander. All details are here, except for crossover, of course 🙂 Any one have any information of parts list for the crossover?

More details are here:
Speaker instructions 2019 | Loudspeakerbuilding

Thanks

Hello,
I have a desktop setup that needs some new speakers.
I think I am highly limited by speaker placement/application and looking for feedback.
Speakers are about 4” off the back wall.
Around 36” apart and 36” from my head.
Can be up to 16” tall by 12” deep by 9” wide.
Budget under $600.
Prefer DIY.
Listen to pretty much everything and genres.
Amps range from 300B set to pp EL84 to pp KT88 to 6V6.

Currently run RBH R5BiR.

Background
This build started as a rebuild of my Infinity 3 Way bookshelf model RS8B speakers. I bought them in the early 80’s and when the surrounds went I made the mistake of replacing the drivers instead of re-foaming. When I measured them about a year ago I discovered how bad the response was. I spent a lot of time trying to model them with the replacement drivers I had used with no luck. Additionally all the drivers are not flush mounted making for some ugly diffractions. I realized that to salvage them I would have to replace the baffle and crossover. At this point I decided to just start over and planned to use the Audax HM170Z0 woofers in a new box and crossover.

Split I2S signal between dac chips

Hi,

I am planning to build a dual-mono dac (first a stereo from usb, then a multichannel from hdmi).
My question is, how can I share the I2S signal with the 2 chips.
So here is my idea. (feel free to make constructive comments)

- There is a clock syncing everything together.

- The USB board (something from alliexpress) provides the I2S signal (which need to be duplicated somehow)

- The I2S is proccessed by 2 pcm1795 (one for each channel). These will be configured to be mono.
- Then the current to voltage conversion will be handled by 2x2 NE5534 opamps (2 for each channel)
- Finally use the pga2311 for volume control (not entirely sure about this: if i give up on dsd, then i will use the dacs internal solution)


The final version will be printed by jlc pcb.

Hi, how are you all?

I'm trying to add this bluetooth module to an amplifier. I have a problem with krc-86b v4.0 module | Electronics Forums

I opened a wall phone charger and soldered it to the AC line inside the amplifier so it
can turn on when i turn on the amp, then soldered the module to the 5v charger. Between the AUX input of the amplifier and the Audio Output of the bluetooth module i used a ground isolator.

The thing is that i'm getting this digital noise when the bluetooth is
not in use. The noise gets better when the bluetooth is in use but it's there.

Any ideas of what to do to remove the noise?

Hi everyone. I got one of an old Yugoslavian record player. It is a iskra-riz traviat stereo. I know this is by no means an audiophile record player but it is a nice looking and pretty decent build quality player and i really want to fix it. Basically when I plugged it in one channel was making a loud humming like when you plug a speaker directly into the mains frequency AC so i quickly turned it off. So I pulled out an amplifier and checked it. There was nothing visible. It has a single diode and a 12v 2000uf capacitor for rectification. I measured 8.5v across the main capacitor. So I tried powering amplifier from my bench power supply. I set the voltage to 8v and current limit to 200ma and gave it an input. This time there was no humming but at first it pulled 150ma and one channel worked perfectly and then when i started to test the bad channel current started to drop and channel started making a squealing noise. I instantly powered it off. But under that squealing I could still hear a very distorted music. Can someone please help me i am now scared to do anything else. I am afraid of blowing up these vintage transistors. It has AC180 and AC181k output transistors.
I recorded a video of a pcb. Here is a link ( don't worry about disconnected main capacitor that was just me testing things...

iskra-riz traviat stereo amplifier board. - YouTube

4 pots are volume and tone control for each channel.

My Android smartphone is weak in recording loud sound events since it crackles destroying every audio detail. So, I tried to find out a good app to enhance the device's microphones. As a result, I got several apps in which most of them require root access. I don't have root access and I'm not willing to do it. Instead, I got VirtualXposed APK which said to be an app that could run root apps without root access. My question, Is it practically possible to apply sound and volume configuration virtually to be effective on the Android OS?

Hi!

Anyone familiar with Ghost resonance? A hardening effect with L-R 24db slopes.






Some info from Lenard Audio

A mid speaker crossed over in isolation. 2nd order 12dB/octave crossovers attenuate the music without hearing a tone or colour change. Higher order crossovers attenuate the music causing a subtle but noticeable tone or colour change (hardening) in the music. When recombined with the other speakers this tonal change is not directly noticeable.
Crossover distortion

Active Crossover are created by electronic L. C. resonant circuits, or software digital assimilations of them. The slopes of crossovers represent a part (one side) of a resonant note. This note is not heard directly, but the steep slopes of third and fourth order crossovers can reflect harmonic interference (sideband distortion) within the music. Early research referred to this ghost resonance as transient distortion. Conclusive research in this area has not been completed.​

Understanding how speakers work and are tested - in simple terms

On the long road to building a better speaker, after some study (possible not enough) and some experimentation (again more is needed) I feel I need to get to the basics here and try to piece together how speakers, and in the broader context, how audio systems work, before I progress any further.

My starting point is the following animation.

How loudspeakers work - Explain that Stuff

The amplfier sends an alternating current to the speaker, the cone of the speaker vibrates at this frequency. Assume a sine wave signal. The vibration is transferred to the air, and reaches the ear. The eardrum vibrates in according to the changing sound pressure and the auditory signal is sensed by the brain.

I have used my own words for clarify and simplicity, and also as a basis for correction.

Sound is transmitted as a transverse wave, consisting of varying sound pressure as shown in this page:

The Nature of Sound

When a sound is created, it is actually a short series of comressions and rarefactions, spanning from a few milliseconds upwards. So there is no single 'sound' as it were, but a short duration sequence of pulses, which are of such short duration we refer to it as 'a sound'

Have I got it right so far?

Hi all,

I was checking the details of these three drivers from Dayton Audio:

• PS220 8" full range
• PS180 6-1/2" full range
• PM180 6-1/2" wideband midbass driver

Looking at the FR curves, and reading whatever I can understand of the spec, I can't see why one is called wideband and the other two are full-range. What am I missing?

I wish the cleverest folks out there would devise a device (maybe an external one) that would mechanically turn the volume knob or stick behind the knob on the TU 8600.

I have ideas but I'm not that mechanically inclined (I'm only handy).

I've seen people take a cheap preamp and place it under their volume knob and have it rotate the unit without a remote by turning a rubber band. That's a start.

Essentially I am asking, hey, we have external power supplies, why not invent an external remote volume device that attaches to the front of the amp?

Now, if one could be fashioned internally--all the better (maybe not sonically)--yet there's no room in the Elekit to do anything internally.

It's 2020--I don't care if it's Elekit or AudioNote or some boutique amp.... I need a remote!!

Like I say these three caps values seem confusing.

Years ago, I bought Bob Brines plans for FT-1600 MkII with Fostex FE167E speakers. My brother and I built them and I absolutely love these speakers. We listen to them every day. After having 3 children, the FE167E have not faired well. They have been colored with crayons, whizzers squished/wrinkled, smooshed, pushed, pulled etc. Ya I know, grills... ugh. Needless to say they are not at their best.

What driver can be used in place of the FE167E?

Not overly fond of the FF165WK's color scheme but have read this is a good drop in for FE167E. Any others that would work well in this enclosure?

Should i put C1 and C2 a cap?
Is it ok to put power DC 18v and Audio in the same cable?

im looking for low noise. i just only need 1uf. 1uf film is so big in my space but if necesarry i will put two each side.

Hi .
Can anyone help with a question that's puzzled me for some time - the RCA type 59, seemingly a IDH version of the 46 triple grid pentode of 1930s is never seen used in any amp (that I can find on the web) I've used these in SE amps successfully for some time. Being in the UK there is little info and so the question - why are they not used? after all, most others of that period are used frequently. Any thoughts appreciated.
Thanks.
David.

i have just put up the Frugel-Horn Project page... and the 1st alpha version may be playing music by the end of the weekend.

http://www.planet10-hifi.com/frugel-horn.html



dave

Hello I am new to this forum looking for help with my receiver. It's a sony str-av210. When I try to set a preset it will set. However if I turn the unit off for more then 10 seconds they reset back to the default. Any idea what could be causing this?

Hi all, & hope all's well.. Here's a pic of the back panel of my Bell & Howell 12643, aka model 138, & the associated schematic (in 2 parts), & not wanting to remove that jack, can anywhere help me make heads or tails of it?
Many thanks in advance for any assistance.
Kenny

Hi! as the title says, does anyone has that spice model? i've been searching and i cant find it nowhere, thanks in advance.

I’m looking for a completed Soekris Dac along the lines of the 1321. I can’t seem to reach Soekris or the US Distributor, Mod House, for a new unit, so figured I’d cast a wider net.

Edit: sounds like the 1321 might be phased out and replaced by an updated version, which explains my issue with finding a new copy. Either way, still looking.

Hi there,
Im looking at a diy dual rail power supply for my naim preamp, +24v 0 0 +24v.
Having trouble locating a dual center tapped transformer? 25 0 25 x2
Can two identical 25 0 25 transformers work?
1 for each rail?

Thanks
Mike

Hi,

Which is the way to go for powering a DSP ADAU 1452?

I have:
-. Aux. output from my Class D amplifier
-. A Meanwell 5v power supply that I can fit inside the case
-. External 12v wall wart

Or maybe adding a DIY RF filter to one of those?

Looking forward to your reply!

built by Ed Padden - sturdy case - USB and coax SPDIF input. Edcor transformers - $135 shipped CONUS. Paypal only.

I am trying to find the source of the 120Hz buzz coming out of my speakers. At least I think it is 120. Anyhow I disconnected all input to the amp and connected the end of the speaker cable to one of the inputs to the scope. The other input to the scope has a 120Hz from a signal generator. Be aware that I am a total newbie to this and I don't really know what I am seeing on the scope from the amp. I expected a much cleaner picture.
So, am I going about this in the correct manner ?
If not, which is likely, please guide me.

I'm planning a TL subwoofer on a napkin, so just doodling.
I've noticed that most TL subs seem to have their vent existing on the same surface as the driver, generally just below it, but Im wondering whether this is absolutely essential?
What I want to do is fit the 15-inch driver to the front of a tallish box, near to the bottom so it is roughly at one-third of the line distance (at S1/S2) and the vent would then exit out of the base, so to speak (so the sub would need to be raised up on feet).
Alternatively, if i flipped it, the driver would be near the top of the front surface facing the listener and the vent would exit out the top towards the ceiling.

Or does this mess up the 'merging' of the front and rear waves?
On first principles, I'd expect no problem with such a design but what do I know?

I'm curious about the digital output (optical & coaxial) from a Yamaha CD-S700 as when hooked up to a Cambridge Audio DacMagic 100, there is no sound even though the correct sample rate lights up on the DAC indicating a locked signal. There is a direct mode on the CD-S700 that turns off the display and digital outputs and have that turned off but have tried both ways. There's no clues in the service manual and there's no menu in the player to play around with settings.

I did read a user on a Dutch site had a similar issue but there was no answer to his question.

The CD-S700 does digital output to my Yamaha AVR with no issues and all other equipment such as TV, CD players, DVD and BD work with the DacMagic 100.

The DAC will not be used with this CD player as was installed for other equipment but has me very curious as I thought digital outputs either optical or coaxial would be standardised.

Hi there,

I'm relatively new to the world of pro audio. I've built a pair of subs and a pair of kick bins that I absolutely love, but I've been using a pretty ratty pair of Eons as the mid tops. I wanted to change that, and threw together a pair of cabinets using the extra birch I had from the kicks and subs. I've attached an image to give you an idea of what they'll eventually look like.

Each cabinet will contain two Eminence Delta 10A speakers sharing the same enclosure volume of almost exactly one cubic foot (and a compression driver/horn in a separate chamber above). I got a great Ebay deal on these four drivers with the intent of building something comparable to the "Small Vented Cab" described by Eminence here (except with two drivers and roughly twice the enclosure volume): https://www.parts-express.com/pedocs/more-info/290-412--eminence-delta-10a-cabinet-design.pdf

My dilemma is that I can't find anywhere sane to put the two 3" ports! My only real solution would be to mount them in the back of the trapezoid, but I've read that ports shouldn't be behind drivers if you can help it. I've also looked at using up to four 2.5" ports on the baffle, but the length of these would be very short to maintain the 95hz tuning frequency of the box I'm going for, and I've read that air velocity is a concern.

One thing worth noting is that I'm designing these to be high passed at 200hz--I think having them play down to 125hz as is possible in the linked Eminence cabinet design might be nice if I need it (say if I were to pair it with just my subs instead of my subs + kick bins).

Sadly, I don't have a windows machine so I can't get WinISD. I'm hoping someone could kindly help me with modeling port air velocity with the four 2.5" (or even four 2") ports (maintaining a 95hz tuning frequency for the 1 cubic foot box) to see if it's untenable at any point 200hz or above.

Alternatively--since the two deltas will be used chiefly for midrange (and not being able to go down to 125hz wouldn't really be a dealbreaker)--should I consider just leaving their enclosure sealed with a volume of 1 cubic foot? I've seen something similar done in this plan, here: Speakerplans.com

If someone is able to model excursion and frequency response in particular, that would be amazing. I'd also love to hear any general opinions regarding vented vs sealed enclosures for PA midrange.

I'm really thrilled to be building speakers and will be certain to keep this community apprised of my progress!

Hi there,

anyone have an opinion on this one? A friend is looking at it but I couldn`t help him much. Will be used with a Bluesound streamer.

looking to get a diy aleph 5 made or if you have one to buy it. anyone out there interested?

I repaired the power supply and 2 shorted irf640's on this memphis amplifier. However something is still damaged. Regulated is +-15, the power supply runs smoothly without the rectifiers. With the rectifiers in curcuit the amplifier flashes in and out of protection, the amplifiers draws about 2.5amps of current then not. Its fast the ammeter just swings as it attempts to power up. I could use some help identifying the problem in this protection curcuit.

Anyone tried the eton series Arcosia drivers? They've been out for a while, but no one talks about them. The Orchestra series is yet not be released.

I’ve had my 8200 DX for a few months and have loved every minute of it. I kept the amp in ultralinear mode since I first plugged it in and loved the sound. I decided to try triode mode this weekend, which is accomplished by cracking the case and moving a small jumper for each channel. Wow! The sound got even better, at least to my ears. I’ve read that amps using triodes tend to have a gorgeous mid-range but a less taut low end. That has been my experience as well with the 8200DX, but the bass sounds quite defined and satisfying all the same. Piano and horns, though, sound like they are in the room with me. The whole sound of my albums is fuller and richer. Maybe I’ll switch back to ultralinear mode in the future, but right now, I am loving how my albums are sounding.

hi all,

I have this amp with shorted output transistors for one channel.
There is a capacitor that connecting rca input positive signal to the secondary ground via a resiator. The designation on the board shows as it is ceramic disk type capacitor but I found 10uf 16v caps. I found those caps burst for two channels. Others two values gone too low. I expecting if somebody had interfered with them or I dont know if it is factory itself. Attaching image of C301 and C401.
Please suggest what to use.

I've seen some interesting hybrid amps about but very little information on how they sound. I'd like to get a bit of a feel for how different approaches to hybrid amps have on the sound.

By hybrid I don't mean some sand somewhere in amongst the glass (such as a CCS plate load) - but something more substantial such as SS gain stage feeding tube output via OPT, or tube gain stage feeding SS output buffer.

Thanks.

I was designing a part of my power supply when I was running trough the datasheet and the basic application notes of the TL431 and I found two images that particularly interested me.

One is a "precision shunt regulator" and the other one is a "precision current limiter".

Firs I want to talk about the current limiter. its essentially a really good constant current source or sink when you use it that way. Its a two wire contraption and it fits perfectly into old tube amplifiers as a CCS to directly replace a resistor because its a two wire device. Doesnt need any power to power a op amp none of that nonsense.
I know its not as easy a a depletion mosfet cascode or a speciffic component meant for CCS. Most of the CCS components are limited with minimum current 8mA and the voltage and so on. (the IXS something something part number if you look in its datasheet more in depth the limmitation is there. Doesn't mean it wont work but its not ideal or bordeline stable)
This could basically work with practically anything. the TL431 is not dependant on the voltage across the entire device so you dont fry it not even if you were to put 600V across it because all the work would have been done in the transistor(dont take this literary because it does not work below 2.5V and some current to open the transistor so there is a lower limit to this). You can put this in the anode or the cathode of any tube. You just need to do some little math to figure the resistor values and voila got your 100% accurate current source / sink.

The second image is the shunt regulator. This one interested me because of a other topic here on the forum where we discussed instabillity caused by drifting bias on the cathode resistor at high loads. I realised we can use the 431 as a shunt regulator so we can set the bias of the tubes on a cathode biased amplifier just like we would in a fixed bias enviroment.
Trained eyes that know something about the 431 would relise that even a EL34 amp like the mullard 5-20 would exceed the voltage capabillity of the 431 (I found the bias voltage on 470R resistors with mine at 450V B+ to be 35-37V and the 431 is maxed in 33). Simple solution put a 15V zener between the 431s anode and the base of the transistor now you got the voltage range extended by the zener voltage so you can even run larger tubes like this. Even KT88s.
And this would be best of all also a drop in two wire replacement for a regular old cathode resistor.
(in the schematic replace the input resistor with a power tubes cathode and VI as the vacuum tubes anode voltage and there you go now you have a rather precise bias that should never fail.) Its like putting zeners in the cathodes but better because you can infinitely adjust it in a certain range. Also the curve of this contraption should be A LOT SHARPER than that of a regular old zener. For stabillity reasons I would leave in the cathode bypass capacitors or replace it with something a lot lower cappacity and something that will never ever go bad (1uF MLCC cappacitor and yes you can get these SMD caps in this capacity at quite the voltage ratings or a film 1uF capacitor, maybe even a SMD tantulum would be okay. It wouldnt be stressed so much anyways.)

All sounds ideal so Ill make this real in full SMD except the power transistor for the shunt regulator. The CCS even at 10mA in a phase inverter (lets say 120V on the cathodes is just 1,2W so I can easily get away with a D2PAK and some heatsinking pads.

Hello,

Have a Topping D50s and would like a bigger soundstage.

As I understand it has a swappable buffer op amp, that currently has a LME49720 op amp. Any suggestions for an op amp in this unit's buffer stage?

(Has ESS9038QM DACs and OPA1612 Soundplus in I/V stage if I understand correctly?)

Any suggestions/advice appreciated?

Hi Happy Xmas to all members.
This is my first experience building a 2.5 way based on Nomex 164 designed by Troel using Peerless HDS midwoofer renamed now Tymphany 830875 and ex Peerless HDS tweeter 810921 now remaned Scanspeak D2608 91300.
In the past I have experienced only 3 ways with 10 in woofer. So I will probably have to tune my ears to bass coming from 6.5 driver asnd hope I shall not be disappointed.

Hello all,


I am considering a FAST-like speaker with :

• Full range Fostex FE126En
• Woofer Monacor SPH-220HQ in 30 litres sealed enclosure
• Monacor SAM-300D plate amp for the woofer

I would like to reach down to 40Hz.

I am afraid that would be misusing the woofer, because when simulating it (WinISD) in a sealed 38 litres I hit xmax with only 15W (out of 100W admissible) with 100dB SPL. Further more, the SAM-300D includes a 3dB bass boost at 40Hz, which adds a little excursion, reducing admissible power.

Is that a design flaw ?
Is the 100dB SPL too low ? I suppose that is RMS value, so what margin does it leave in terms of crest factor headroom, could I actually play music at 100dBrms SPL ?

I don't particularly play music loud, I just want to avoid an undersized system (FWIW the room is about 5m x 5m 3m ceiling, open into a 2nd room the same size, open into a third).

Thanks for your advice and input.

What do we know about the W6-1914SB? I ran across this 6in honeycomb diaphragm neodymium motor midrange today. I looked at the response curve and it seems wide and flat and with decent sensitivity. I think it won’t make much bass but could be a good top for a FAST/WAW.








Data sheet:
https://www.parts-express.com/pedocs/specs/264-905--tang-band-w6-1914sb-spec-sheet.pdf

In power amplifiers of this series are to find two kind of electrolytic capacitors behind the rectifier :

A. Large can versions with screw terminals and low-ESR e. g.
FTcap (F&T) GMB 47310075145 (Ø 75mm x 145mm, ESR = 3-4 mΩ)
%product-title% kaufen
or similar like Mallory, Cornell-Dublier or Sprague
NOS Mallory 10,000UF 75VDC CGS103U075V3C Electrolytic Can Capacitor.
https://static6.arrow.com/aropdfcon...f45da10ee14f2ad1ac33/3632267624208725550c.pdf
Sprague 36DE213G050BB2A 21000uF 50V Aluminum Electrolytic Capacitor: Amazon.com: Industrial & Scientific

The following models use this kind of capacitor
1) X-150 (not X-150.5)
2) X-350, X-350.5, X-350.8
3) X-600, X-600.5
4) X-1000 (from X-series first amplifier ever)
5) XS-150 (two devices /each channel due to outdoor power supply)

B. Small versions (mounting type "Snap-In") with high capacity in large quantity e. g.
Panasonic ECO-S1HP103CA (Ø 25mm x 50mm, ESR = 36/27 mΩ)
Blocked
or similar:
Nichicon LLS1K472MELA/LLS1J682MELA/LGU1H682MELA/LGU1J472MELA
https://uk.rs-online.com/web/p/aluminium-capacitors/8526298/
https://eu.mouser.com/ProductDetail/Nichicon/LLS1J682MELA?qs=CTiUoleKpMEAuBr9VqiAJg==
https://uk.rs-online.com/web/p/aluminium-capacitors/1671486/
https://uk.rs-online.com/web/p/aluminium-capacitors/8466962/
EPCOS B41252A8478M000
https://uk.rs-online.com/web/p/aluminium-capacitors/7714721/
Vishay (formerly BC) MAL225631682E3
https://uk.rs-online.com/web/p/aluminium-capacitors/1730638/
KEMET (formerly BHC-Aerovox) ALC70A472BD063
https://mt.rsdelivers.com/product/k...μf-electrolytic-capacitor-63v-dc-snap/1813462

The following models use this kind of capacitor - at least according the top view images without cover:
1) X-150.5 (not X-150)
2) X-250, X-250.5, X-250.8
3) XA-25
4) XA-30.5, XA-30.8
5) XA-100.5
6) XA-200, XA-200.5

The great advantage of using large can versions are lowest ESR, very reliable and very long life time 10000-15000 hours) so as best possible sound results in all respects.
Disadvantage here is high space requirement and very high costs, even when considering volume discounts.

The great advantage of using small versions is very low cost and the very little need of space required with a very high total value of capacity. Disadvantage here is the short life time around 2000-4000 hours -at least according the datasheets and poor dynamic behavior in listening tests compared to bulky and space-consuming capacitors with screw terminals.

And now my questions:
1) What is it based on, when to use the small (Ø 25mm) caps (small cv product) and when to use the large capacitor cans with screw terminals?
2) When buying X-XA-XS power amp devices in used condition, it is better to prefer the ones with screw terminated can electrolytic cap versions ?

Thank you very much for an advice.
In the attachment images from X-150 and X-150.5

--- Hammer Dynamics Super 12 Speaker NOS speaker -- KIT -- for sale asking $599.00 - A great Full Range Speaker KIT!

-- 97 db Speaker - works well with Tube or Solid state

--Full Range Driver

--Small coaxial mounted Tweeter

-- Kit actually cost -- $ 1,260.00 in it's final year .

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=32729&stc=1&d=1212251296

nice little chokes for those low current tube demands

$45 a pair including shipping in a medium ($15.05) Priority box.

screw spacing ~ 1 5/8"

Paypal only

the thd for this circuit has been measured at 10KHz 10W as 0.002%, however my in my sims i get 0.03% 😕


https://www.diyaudio.com/forums/group-buys/307077-peeceebee-v4-gb.html

I have not been on the forum for quite a while and I expected to find the definitive amplifier protection circuit had been developed and accepted as the ultimate circuit but my search did not discover such. Is there a circuit that is, more or less, considered the best for high power DC output amplifiers?

Hi all,

First time poster here. I just recently bought a Denon PMA 1060 stereo amplifier which has an issue. The audio will cut out at about quarter volume. The actual volume varies slightly with different music (louder music will cut out at a lower volume, quieter music will cut out at slightly higher volume). I have to power cycle the amp to restore audio but if I go too loud again, it will cut out.

I'm guessing the protection circuit has kicked in but don't know why.

I've checked for stray strands of speaker wire, but I use banana plugs and don't see any stray wires.
I have tried left and right channels connected by themselves, with no change.
I have tried the second (B) set of speaker terminals, no difference.

The speakers connected are Aaron ATS4, rated at 160W at 6 ohm so should be able to handle the power. The amplifier I replaced but is still working doesn't cut out with these speakers at quite loud volume.

I do have a multimeter, but am not strong with amplifiers or analog electronics. I've measured the voltage across the speaker terminals and there does not appear to be a big DC offset voltage on the terminals. I've found a service manual online and there is a procedure to adjust the idle current, but I don't think that would cause this issue, would it? From what I've read, too high idle current makes the amp run hot, and too low affects sound quality. I don't think either of this is happening in this case.

I'm wondering if anyone knows what the issue might be? I can take it to a repair shop who seem confident on what the problem is, but wondering if it's a cheap and/or common fix, or more complex!

Thanks in advance.

Hi ! sorry if i jump in but i really need some advice on car audio amps.
First of all i have absolutely no experience with car audio.
I do not listen when i drive for safety reasons (the music distracts me a lot).
Anyway ... i see many car audio amps around ... new and used.
So i thought about using one of them as a power amp in my stereo system.
I have already bought this to power it ...

LEDMO 12V 20A Alimentatore Interruttore AC 110/240V to DC Trasformatore di Alimentazione 240W: Amazon.it: Fai da te

One thing that i like very much is the gain control that can be found on i guess all car audio amp. I have a preamp with a high gain and that attenuator could be very useful for me.
So the question is ... what to buy ? i really need only 20-30 Watt/channel but with good current
Any advice and suggestion would be very welcomed and appreciated.
Kind regards, gino

Hello, I'm fairly new to the world of solid state amps, more of a tube guitar amp guy. A buddy brought me a Parasound HCA1000A which needed new filter caps. The amp seems to be working fine now but I would like to verify that the bias is correct. My understanding is that the bias calculation/adjustment procedure is to measure voltage across output transistor emitter resistors then use ohms law to drive current and adjust for 30-40 mA. So I'm measuring voltage on the
0.33 ohm emitter resistors on the big 2SC3519 and 2SA1386 transistors but I measure 0V on all of them. Is there something I'm doing wrong?

J.