various TUBES triodes : pentodes
selling some tubes left in my garage : 8x 71A DHT triode ( 6 globe : 2st shapes NOS) 150€
4 type 26 globe DHT 100€
pair of pentode 350B ( 6L6) NOS 100€
pair of pentode MULLARD EL33 NOS 100€
pair of pentode Tungsol 5881 ( 6L6) 60€
pair of RCA 2A3 NOS 150€
pair of rectifier RCA 5R4GY NOS 80€
shipping included for all E.U
thanks.
4 type 26 globe DHT 100€
pair of pentode 350B ( 6L6) NOS 100€
pair of pentode MULLARD EL33 NOS 100€
pair of pentode Tungsol 5881 ( 6L6) 60€
pair of RCA 2A3 NOS 150€
pair of rectifier RCA 5R4GY NOS 80€
shipping included for all E.U
thanks.
ALLO Digi One Signature + Khadas Tone Board
I'm selling an Allo Digi One Signature with acrylic case(SOLD) +
Khadas Tone Board + Aluminium Case(SOLD)
I bought it for an project but I never used it, it's tested and works fine. I'm asking 130€ for the Digi One Signature
and 35€ for the KHADAS Tone Board
+ shipping
Khadas Tone Board + Aluminium Case(SOLD)
I bought it for an project but I never used it, it's tested and works fine. I'm asking 130€ for the Digi One Signature
and 35€ for the KHADAS Tone Board
+ shipping
Quad 34 setting higher outut level than standard 0,5Volts
- Analog Line Level
- 2 Replies
I want to gain output level for an Quad 34 preamplifier. Seems to be pretty straightforward with this attached guide.
Simply change R118 and 121 for a short and put 3,3Kohs in R119 and 122. This done to be able to have the right inputlevel for a old Quad 2 who likes 1,6volts . I also have a bunch of 33s and others that reqire 0,5V.
I have seen others set a potentiometer in the back of the 34 to be able to change output settings. Anyone now how to do this mod?
Simply change R118 and 121 for a short and put 3,3Kohs in R119 and 122. This done to be able to have the right inputlevel for a old Quad 2 who likes 1,6volts . I also have a bunch of 33s and others that reqire 0,5V.
I have seen others set a potentiometer in the back of the 34 to be able to change output settings. Anyone now how to do this mod?
Can anyone ID this 3-way or any of its drivers?
Does this look familiar to anyone, either the unit as a whole, or the individual drivers?
Note the woofer has a 5-hole mounting pattern.
Apologies for poor pic quality 🤢
Note the woofer has a 5-hole mounting pattern.
Apologies for poor pic quality 🤢
DM601-S3, DSP based active bi-amp design and result
A month ago I have modified B&W DM601-S3 crossover according to Rutcho's design but I have noticed that the top end is too suppressed and it sounds dull and lifeless. Now I have completely removed the passive crossover with a remaining 10uF film cap (Janzten Standard-Z Cap 400v) in the tweeter signal line and used DSP crossover and 2 separate amplifier channels to drive the speakers. I used an AV-Receiver with HDMI input and 5.1 output (Yamaha RX-V373). The PC runs Ubuntu Server 20.04 with Media Player Daemon, Ecasound and Richard Taylor's LADSPA plug-ins. PC connects to AV-Receiver using HDMI audio. The front L/R channels are connected to the Woofer (LF) input of the speaker. Surround L/R channels are connected to the Tweeter (HF) input of the speaker and Subwoofer pre-out is connected to the subwoofer. With appropriate settings in the software the digital music source is being split into HF/LF/Sub sections and sent to each respective channels.
The software I used is VituixCAD. I firstly re-created the factory crossover in the simulation, with the approximate tweeter offset of 28mm, I am able to fairly accurately simulate the response. Then I spent a couple of weeks running simulations using all sorts of different configurations and came up with this final arrangement in the 2nd picture. The result is a ruler flat response with +/- 1db accuracy from 200Hz to 15Khz and an intentional slight drop off at the top end. The phase matching is as close as I could get, with two drivers matching closely from 2.5Khz all the way up to 7.5Khz. The crossover frequency is same as factory setting at 4Khz since the tweeter's Fs is at 2Khz and I don't feel comfortable crossing it any lower.
The settings is as follows: Mid-woofer has a 4th order LR low-pass filter at 3.5Khz and a Parametric EQ filters to counter for elevated response at 1.3Khz. The drop off at the lower end is because I crossed it over with the subwoofer at 80Hz and the 4th order LR high-pass filter is also embedded in mid-woofer's DSP parameters. The tweeter is a bit more complex. It consists a 4th order LR high-pass filter at 3.7Khz, a high-shelf filter at 15Khz to fix tweeter's top end droop and another 1st order high-pass filter at 3.7Khz. Together with the 10uF series capacitor it forms a 6th order filter crossed at 4Khz. This is because woofer and tweet have different rate of roll off at the crossover frequency and it must also be taken into consideration. Tweeter is padded down electronically at -3.5db so padding resistor is not needed. As a result the amp should have better damping factor to control the tweeter. Phase of tweeter is inverted, also electronically, to bring it closer to the phase of the woofer at the crossover frequency range. A delay of 76us is added to adjust the phase of the tweeter so it matches exactly the woofer's phase at 4Khz.
As a result, both drivers have steep roll off after crossover so woofers' break up and tweeter's resonance have been reduced to minimum. Tweeter at Fs of 2Khz is already -30db down and woofer's worst break up at 10Khz is off the chart (probably -40db down).
The next step is to fine tune the delay. I used the approximated 28mm tweeter Z offset as a starting point. Invert the tweeter phase (which is now as easy as editing one parameter in the dsp) then adjust the delay until I get the deepest null at the crossover frequency when running a frequency sweep.
For now it already sounds really good. Lots of details in the top end while not being shrill at all. Mid range is very tight and immediate. Along with a flat response and tight phase matching, it sounds a lot cleaner than before.
I have converted the CAD design into Linux Ecasound profile so if anyone is interested in doing Linux PC based DSP can look at them:
tweeter.ecp
# Tweeter driver
tweeter = -el:RTlr4hipass,3700 -el:RThighshelf,3,15000,1 -el:RThighpass1,3700 -eadb:-3.5 -ea:-100 -el:delay_0.01s,0.000076
mid.ecp
# Mid-woofer driver
mid = -el:RTlowshelf,5,80,0.65 -el:RTlr4hipass,80 -el:RTlr4lowpass,3500 -el:RTparaeq,-4,1300,0.8
woofer.ecp
# Subwoofer
woofer = -el:RTlr4lowpass,80
Audio-output section of mpd.conf:
audio_output {
type "pipe"
name "HDMI 5.1 DSP Crossover/EQ"
command "ecasound -q -z:nodb -z:mixmode,sum -a:woofer,mid,tweeter -f:s32\_le,2,44100 -i:stdin -a:woofer -
pf:/etc/woofer.ecp -chmix:1 -chorder:0,0,0,0,0,1 -a:mid -pf:/etc/mid.ecp -chorder:1,2,0,0,0,0 -a:tweeter -pf:/etc/tweeter.ecp -chorder:0,0,1,2,0,0 -a:woofer,mid,tweeter -f:16,6,44100 -o:alsa,hdmi:CARD=PCH,DEV=0"
format "44100:32:2"
}
The DSP software configuration I did was according to the blog by Richard Taylor: https://rtaylor.sites.tru.ca/2013/06/25/digital-crossovereq-with-open-source-software-howto/
The Crossover hardware upgrade I did was according to the article by Rutcho: http://rutcho.com/tweaks/01_bw_dm601s3/bw_dm601s3.html
Image 1: Original crossover simulated in VituixCAD
Image 2: DSP crossover simulated in VituixCAD
Update: I think I made a mistake of ignoring the Y axis offset between tweeter and woofer. I have added the measured 135mm vertical offset to the woofer and had to update the Z offset of tweeter and delay to make it work. The result is the tweeter delay has been modified from 71us to 76us. I have also removed a 1db Param EQ on the woofer which is more or less useless and only complicates things. I haven't done the actual measuring yet as I don't have a calibrated mic and I will try to get one soon.
One more thing I cannot enphase enough: Have a tweeter protection cap at all times! When I test ran this setup, the software configuration was incorrect so I ended up sending full range audio signal to both drivers. The tweeter sounded so loud and has more low frequency signal that I remember, until I discovered that the DSP plugins were not at the right place and the software couldn't find them! If I didn't have that 10uF cap in there my tweeters would have already been blown. I almost learned it the hard way so I will always have a cap in tweeter's signal line because the risk is not worth any sonic improvement of removing it.
I am pretty new to speaker design and measurement. I appreciate if people here can point out any obvious issues that I'm not aware of.
The software I used is VituixCAD. I firstly re-created the factory crossover in the simulation, with the approximate tweeter offset of 28mm, I am able to fairly accurately simulate the response. Then I spent a couple of weeks running simulations using all sorts of different configurations and came up with this final arrangement in the 2nd picture. The result is a ruler flat response with +/- 1db accuracy from 200Hz to 15Khz and an intentional slight drop off at the top end. The phase matching is as close as I could get, with two drivers matching closely from 2.5Khz all the way up to 7.5Khz. The crossover frequency is same as factory setting at 4Khz since the tweeter's Fs is at 2Khz and I don't feel comfortable crossing it any lower.
The settings is as follows: Mid-woofer has a 4th order LR low-pass filter at 3.5Khz and a Parametric EQ filters to counter for elevated response at 1.3Khz. The drop off at the lower end is because I crossed it over with the subwoofer at 80Hz and the 4th order LR high-pass filter is also embedded in mid-woofer's DSP parameters. The tweeter is a bit more complex. It consists a 4th order LR high-pass filter at 3.7Khz, a high-shelf filter at 15Khz to fix tweeter's top end droop and another 1st order high-pass filter at 3.7Khz. Together with the 10uF series capacitor it forms a 6th order filter crossed at 4Khz. This is because woofer and tweet have different rate of roll off at the crossover frequency and it must also be taken into consideration. Tweeter is padded down electronically at -3.5db so padding resistor is not needed. As a result the amp should have better damping factor to control the tweeter. Phase of tweeter is inverted, also electronically, to bring it closer to the phase of the woofer at the crossover frequency range. A delay of 76us is added to adjust the phase of the tweeter so it matches exactly the woofer's phase at 4Khz.
As a result, both drivers have steep roll off after crossover so woofers' break up and tweeter's resonance have been reduced to minimum. Tweeter at Fs of 2Khz is already -30db down and woofer's worst break up at 10Khz is off the chart (probably -40db down).
The next step is to fine tune the delay. I used the approximated 28mm tweeter Z offset as a starting point. Invert the tweeter phase (which is now as easy as editing one parameter in the dsp) then adjust the delay until I get the deepest null at the crossover frequency when running a frequency sweep.
For now it already sounds really good. Lots of details in the top end while not being shrill at all. Mid range is very tight and immediate. Along with a flat response and tight phase matching, it sounds a lot cleaner than before.
I have converted the CAD design into Linux Ecasound profile so if anyone is interested in doing Linux PC based DSP can look at them:
tweeter.ecp
# Tweeter driver
tweeter = -el:RTlr4hipass,3700 -el:RThighshelf,3,15000,1 -el:RThighpass1,3700 -eadb:-3.5 -ea:-100 -el:delay_0.01s,0.000076
mid.ecp
# Mid-woofer driver
mid = -el:RTlowshelf,5,80,0.65 -el:RTlr4hipass,80 -el:RTlr4lowpass,3500 -el:RTparaeq,-4,1300,0.8
woofer.ecp
# Subwoofer
woofer = -el:RTlr4lowpass,80
Audio-output section of mpd.conf:
audio_output {
type "pipe"
name "HDMI 5.1 DSP Crossover/EQ"
command "ecasound -q -z:nodb -z:mixmode,sum -a:woofer,mid,tweeter -f:s32\_le,2,44100 -i:stdin -a:woofer -
pf:/etc/woofer.ecp -chmix:1 -chorder:0,0,0,0,0,1 -a:mid -pf:/etc/mid.ecp -chorder:1,2,0,0,0,0 -a:tweeter -pf:/etc/tweeter.ecp -chorder:0,0,1,2,0,0 -a:woofer,mid,tweeter -f:16,6,44100 -o:alsa,hdmi:CARD=PCH,DEV=0"
format "44100:32:2"
}
The DSP software configuration I did was according to the blog by Richard Taylor: https://rtaylor.sites.tru.ca/2013/06/25/digital-crossovereq-with-open-source-software-howto/
The Crossover hardware upgrade I did was according to the article by Rutcho: http://rutcho.com/tweaks/01_bw_dm601s3/bw_dm601s3.html
Image 1: Original crossover simulated in VituixCAD
Image 2: DSP crossover simulated in VituixCAD
Update: I think I made a mistake of ignoring the Y axis offset between tweeter and woofer. I have added the measured 135mm vertical offset to the woofer and had to update the Z offset of tweeter and delay to make it work. The result is the tweeter delay has been modified from 71us to 76us. I have also removed a 1db Param EQ on the woofer which is more or less useless and only complicates things. I haven't done the actual measuring yet as I don't have a calibrated mic and I will try to get one soon.
One more thing I cannot enphase enough: Have a tweeter protection cap at all times! When I test ran this setup, the software configuration was incorrect so I ended up sending full range audio signal to both drivers. The tweeter sounded so loud and has more low frequency signal that I remember, until I discovered that the DSP plugins were not at the right place and the software couldn't find them! If I didn't have that 10uF cap in there my tweeters would have already been blown. I almost learned it the hard way so I will always have a cap in tweeter's signal line because the risk is not worth any sonic improvement of removing it.
I am pretty new to speaker design and measurement. I appreciate if people here can point out any obvious issues that I'm not aware of.
FS: SEAS W15CH001 [x2]
Gently used in a project that I retired several years ago. Have been boxed in temperature/humidity controlled environment. In perfect functional condition and shows few signs of use. Brilliant drivers when properly implemented into a design, IMO. $435/pair CONUS shipped including PayPal G&S fees.
OB Single Driver Eq
- By peppennino
- Pass Labs
- 22 Replies
The idea comes from Papa's Equalizer presented by Dana on BA2021, talking about next Speaker Camp event. Nelson made a small Eq in order to give a bump on lower freqs, something similar as seen to ACN/B5.
So, as it could be very helpful for large OB speakers with single driver (only the fullrange), why not combine that cell with a variable notch like on B5? It will probably be amazing with big fullranges like AN or Lii (especially 15 and 18"). What do you think?
Cheers,
Vinz
So, as it could be very helpful for large OB speakers with single driver (only the fullrange), why not combine that cell with a variable notch like on B5? It will probably be amazing with big fullranges like AN or Lii (especially 15 and 18"). What do you think?
Cheers,
Vinz
LifeO4 pure power supply MkII with battery holder + ES9028Q2M DAC HAT
LifeO4 pure power supply MkII withsoldered battery holders
Since I collected a lot of parts in the past for projects I planned but for different reasons
never started. I now have to clean up a little bit.
I have a IAN Canada LifeO4 pure power supply MkII Board with soldered Battery holders, only used some hours for testing.
140,00€, shipping included within EU, for other countries please ask for shipping costs. SOLD!!!
+ an unopened IAN Canada 9028Q2M DAC HAT for 35,00€, shipping included
Since I collected a lot of parts in the past for projects I planned but for different reasons
never started. I now have to clean up a little bit.
I have a IAN Canada LifeO4 pure power supply MkII Board with soldered Battery holders, only used some hours for testing.
140,00€, shipping included within EU, for other countries please ask for shipping costs. SOLD!!!
+ an unopened IAN Canada 9028Q2M DAC HAT for 35,00€, shipping included
busted the potentiometer on my Thorens TD203
- By amiga505
- Analogue Source
- 10 Replies
hello. yesterday while trying to adjust the speed on my Thorens TD203 turntable I busted the 33 1/3 RPM potentiometer, now no matter how much I rotate it, nothing happens. I looked it up, apparently this happens a lot as the thing is very tender and the instruction manual makes this task look rather simple. after the 33 1/3 RPM debacle I unscrewed the controller housing and adjusted the 45 RPM potentiometer live, applying caution - this worked like a charm. so, the question is - can the 33 1/3 RPM potentiometer be replaced? also, could I perhaps get away with an affordable variable (bench) PSU? if I understand correctly, I need to adjust DC voltage the motor receives.
whazza "Hyper Bass Reflex" ?
- By freddi
- Subwoofers
- 11 Replies
[ DIY ] Hyper Bass-Reflex Type Enclousures (for Single Driver) - DIY - Loudspeaker | Low-end Speaker Craft
tough to wrap pea-brain around this thing and how it might vary as the maker
works with little fullrange drivers - in the try below, it looks like a MLTL
Rough stab at a "hyper bass reflex" roughly using the "rules" below for the low qts B&C 12pe32 vs similar bulk reflex
Hyper Bass Calculations
tough to wrap pea-brain around this thing and how it might vary as the maker
works with little fullrange drivers - in the try below, it looks like a MLTL
Rough stab at a "hyper bass reflex" roughly using the "rules" below for the low qts B&C 12pe32 vs similar bulk reflex
Hyper Bass Calculations
High frequency roll-off
- By jcalvarez
- Tubes / Valves
- 17 Replies
Hello everyone!
I have been doing some bandwidth measurements on a SE prototype amp, and I can see a decrease of the output voltage at higher frequencies, reaching -2.5dB at 20Khz (pure resistive load):
I have checked the levels at g1 of the output tubes, varies very little:
1Khz: 106Vpp
20Khz: 103Vpp
The only think left is the output transformer, which is from Aliexpress. Should I assume most of the high frequency roll-off is happening due to the output transformer? The amp is not using global negative feedback, below the schematic for reference.
Link to the output transformer: https://www.aliexpress.com/item/4000899015634.html?spm=a2g0o.order_list.0.0.367c18020HinhR
Thank you!
I have been doing some bandwidth measurements on a SE prototype amp, and I can see a decrease of the output voltage at higher frequencies, reaching -2.5dB at 20Khz (pure resistive load):
I have checked the levels at g1 of the output tubes, varies very little:
1Khz: 106Vpp
20Khz: 103Vpp
The only think left is the output transformer, which is from Aliexpress. Should I assume most of the high frequency roll-off is happening due to the output transformer? The amp is not using global negative feedback, below the schematic for reference.
Link to the output transformer: https://www.aliexpress.com/item/4000899015634.html?spm=a2g0o.order_list.0.0.367c18020HinhR
Thank you!
Cary SLA-70B biasing issue
- By Jaybird840
- Tubes / Valves
- 0 Replies
Hi All,
I recently acquired this Cary Audio SLA-70B and am really surprised at how good it sounds. I've had a couple of other Cary amps, and this one is the best of them. Anyway, the previous owner had broken a tube, and replaced it with a mismatch. I just plopped in a quad of cheaper chinese el34's to make sure it is up and running in good health. I went to bias the tubes, and discovered that the procedure outlined in the Cary literature doesn't work. The tube fuse has been completely bypassed somehow--you can remove the fuse, and the amp still runs fine. Upon internal inspection, it is obvious why--the fuse socket is disconnected. So that leaves me trying to figure out how to bias it. I have circled what I believe is the biasing pot in blue on the picture. I attempted to measure the current below the resistor that sits between the pot and where it is grounded on the capacitor, but could not get any current to register with the amp on and warm. Any guidance would be appreciated. I would also be interested in rewiring the tube fuse back into the circuit. --Jaybird
I recently acquired this Cary Audio SLA-70B and am really surprised at how good it sounds. I've had a couple of other Cary amps, and this one is the best of them. Anyway, the previous owner had broken a tube, and replaced it with a mismatch. I just plopped in a quad of cheaper chinese el34's to make sure it is up and running in good health. I went to bias the tubes, and discovered that the procedure outlined in the Cary literature doesn't work. The tube fuse has been completely bypassed somehow--you can remove the fuse, and the amp still runs fine. Upon internal inspection, it is obvious why--the fuse socket is disconnected. So that leaves me trying to figure out how to bias it. I have circled what I believe is the biasing pot in blue on the picture. I attempted to measure the current below the resistor that sits between the pot and where it is grounded on the capacitor, but could not get any current to register with the amp on and warm. Any guidance would be appreciated. I would also be interested in rewiring the tube fuse back into the circuit. --Jaybird
Marti CLA40-H Modification Help ( First Mod Project )
- Parts
- 0 Replies
Hey all, I recently bought a Marti Electronics CLA-40H and I'm going about making some aesthetic changes. I'm going to relocate a bunch of switches as well as get a new aluminum faceplate. This is my first big project! Any help at all would be amazing. The first three pictures below is the way it looks now and the last picture is the type of mod I'm aiming to achieve.
Marti CLA40-H Manual
Switch Type Changes & Relocation
There are two switches on the back that I'd like to change from slide switches to Potentiometers and move to the front. Any advice or help finding them would be much appreciated.
1. The first one Is a Stackpole DPDT Switch ( 3a 125vac, 1.5a 250vac, .5a 125vdc ).
2. The second one is a DPDT Switch from switchcraft ( 3a 125vac, .5a 125vdc )
On/Off Switch
There doesn't appear to be an On/Off Switch. Where in the circuit would I add that? And how!? Like the one below
On/Off Light
Like the picture below I'd like to add an On/Off Light. Where in the circuit would I add that? And how!?
Thank you for any help you can provide
Marti CLA40-H Manual
Switch Type Changes & Relocation
There are two switches on the back that I'd like to change from slide switches to Potentiometers and move to the front. Any advice or help finding them would be much appreciated.
1. The first one Is a Stackpole DPDT Switch ( 3a 125vac, 1.5a 250vac, .5a 125vdc ).
2. The second one is a DPDT Switch from switchcraft ( 3a 125vac, .5a 125vdc )
On/Off Switch
There doesn't appear to be an On/Off Switch. Where in the circuit would I add that? And how!? Like the one below
On/Off Light
Like the picture below I'd like to add an On/Off Light. Where in the circuit would I add that? And how!?
Thank you for any help you can provide
Afternoon Delight
- Music
- 7 Replies
I noticed "Afternoon Delight" on the "One Hit Wonders" thread on another board earlier this week. It was a No. 1 hit in 1976.
They never had anything in even the top fifty again.
I hadn't heard it in decades but I've always liked the harmonies.
I noticed a copy on eBay for £3.99 with free postage, so I said, "hang the expense" and bought it.
I'd bought another single a month or so ago, but hadn't yet put it in one of my jukeboxes.
So I've been on one of my jukebox enthusiast's website and downloaded the title cards in PDF form to cut out and use. This is a free service, I hate seeing jukeboxes with hand-written title cards.
You go on the site, type 'em up in styles, colours and fonts of your choice and print them off.
![[IMG]](https://www.gardening-forums.com/attachments/screenshot-2022-05-07-120206-png.89621/ "[IMG]")
I bought the Rainbow one on eBay a few weeks ago for about the same money.
Forty-two years ago, we had a birthday party for my wife's 40th birthday.
There were a few of my friends there from my squash club, but mostly hers, who were of similar ages. I'd made up a few cassette tapes of contemporary popular music that would appeal mostly to her friends, but included these two. There was a bit of a shocked reaction from some of her friends, unfamiliar with heavy metal. It always makes me smile when I think about it. I've not yet put it in.
Anyway, the new record arrived today. Unlike iPods, if you want to put a different record in a vinyl jukebox, you have to choose one to take out. In this case Stevie Wonder has joined many others in my "retro" record rack.
There you go.
Login to view embedded media
They never had anything in even the top fifty again.
I hadn't heard it in decades but I've always liked the harmonies.
I noticed a copy on eBay for £3.99 with free postage, so I said, "hang the expense" and bought it.
I'd bought another single a month or so ago, but hadn't yet put it in one of my jukeboxes.
So I've been on one of my jukebox enthusiast's website and downloaded the title cards in PDF form to cut out and use. This is a free service, I hate seeing jukeboxes with hand-written title cards.
You go on the site, type 'em up in styles, colours and fonts of your choice and print them off.
I bought the Rainbow one on eBay a few weeks ago for about the same money.
Forty-two years ago, we had a birthday party for my wife's 40th birthday.
There were a few of my friends there from my squash club, but mostly hers, who were of similar ages. I'd made up a few cassette tapes of contemporary popular music that would appeal mostly to her friends, but included these two. There was a bit of a shocked reaction from some of her friends, unfamiliar with heavy metal. It always makes me smile when I think about it. I've not yet put it in.
Anyway, the new record arrived today. Unlike iPods, if you want to put a different record in a vinyl jukebox, you have to choose one to take out. In this case Stevie Wonder has joined many others in my "retro" record rack.
There you go.
Login to view embedded media
Yamaha B-2
- Solid State
- 5 Replies
Been hunting for one for some time, but wasn't going to spend 2k, ormore and then have to go through it all on top of it. I found one that has a few dings and made an offer for 1k. The guy took it, so sometime if the next month I will have this wonderful old girl on the lab.
Let's hope I didn't get hosed.
Hell as long as the FETs are good, I can't lose anyway. It was said that it is working fine, we shall see.
JT
Let's hope I didn't get hosed.
Hell as long as the FETs are good, I can't lose anyway. It was said that it is working fine, we shall see. JT
6SL7 or 6SL7GT for broken Tubalizer
- By Sonusthree
- Tubes / Valves
- 108 Replies
6sl7 or 6sl7GT for Broken Tubalizer
Hi everyone,
I have just received an Audiodigit tubalizer that unfortunately isn't very healthy.
http://www.audiodigit.com/?section=81
This is my first experience of valves and hopefully will lead to more adventurous things.
THe Tubalizer is placed between my CD Player and Integrated (14KOhm input impedance) solid state amplifier.
It distorts very badly with any input. It is slightly better with very small signals (-12dB) but not at all satisfactory. I have tried many sources and different power supplies and 'tuning' settings.
I am using a 12v 1.2Amp regulated linear supply with the correct polarity. I have also tried other supplies with no change. My power supply gives 12.06 Volts (unloaded) and the regulator is passing approximately 6 Volts and the tube glows slightly near the top as it should.
I have redone all the soldering to be sure and measured 5.7Volts at the ground of the RCA outputs (This is as it should be.)
This device is only made from a handful of caps and resistors with a 6 Volt regulator and a Sovtek 6SL7.
Surely it must be a faulty Tube? What else could be wrong here? Any help would be very much appreciated. I would eventually like it to be my CD players output device when I get it working.
I feel I should buy a spare valve for test purposes but what is the difference between a 6sl7 and a 6sl7GT?
Please help
Hi everyone,
I have just received an Audiodigit tubalizer that unfortunately isn't very healthy.
http://www.audiodigit.com/?section=81
This is my first experience of valves and hopefully will lead to more adventurous things.
THe Tubalizer is placed between my CD Player and Integrated (14KOhm input impedance) solid state amplifier.
It distorts very badly with any input. It is slightly better with very small signals (-12dB) but not at all satisfactory. I have tried many sources and different power supplies and 'tuning' settings.
I am using a 12v 1.2Amp regulated linear supply with the correct polarity. I have also tried other supplies with no change. My power supply gives 12.06 Volts (unloaded) and the regulator is passing approximately 6 Volts and the tube glows slightly near the top as it should.
I have redone all the soldering to be sure and measured 5.7Volts at the ground of the RCA outputs (This is as it should be.)
This device is only made from a handful of caps and resistors with a 6 Volt regulator and a Sovtek 6SL7.
Surely it must be a faulty Tube? What else could be wrong here? Any help would be very much appreciated. I would eventually like it to be my CD players output device when I get it working.
I feel I should buy a spare valve for test purposes but what is the difference between a 6sl7 and a 6sl7GT?
Please help
Python Software AWG for SDS1404X-E
- By NickKUK
- Equipment & Tools
- 46 Replies
A Sunday evening project.
The python AWG project allows a PC to work as an intermediary for the non Siglent AWG for producing Bode plots: GitHub - 4x1md/sds1004x_bode: Bode plot with Siglent SDS1004X-E oscilloscopes and a non-siglent AWG.
Now there's a couple of other options - including AS9850 etc but the most simple example would be to have python create a wave file and play it.
So I'm making a software 'driver' for the git hub software that simply acts as if it was a AWG using the headphone output as the audio output.
The above is the basic structure as an example from the web. It shouldn't be too difficult to change the AWG to use this. Naturally this has all the mac mini filters in the way.. but the same could be done using a PI etc.
After much gnashing of teeth - I managed to get the Ubuntu VM inside VirtualBox running on my Mac mini connected by ethernet to allow the connection from the SDS1104-E. The bode plot is random output as I've not actually got the probes connected to anything!
The python AWG project allows a PC to work as an intermediary for the non Siglent AWG for producing Bode plots: GitHub - 4x1md/sds1004x_bode: Bode plot with Siglent SDS1004X-E oscilloscopes and a non-siglent AWG.
Now there's a couple of other options - including AS9850 etc but the most simple example would be to have python create a wave file and play it.
So I'm making a software 'driver' for the git hub software that simply acts as if it was a AWG using the headphone output as the audio output.
Code:
import numpy as np
import simpleaudio as sa
frequency = 440 # Our played note will be 440 Hz
fs = 44100 # 44100 samples per second
seconds = 3 # Note duration of 3 seconds
# Generate array with seconds*sample_rate steps, ranging between 0 and seconds
t = np.linspace(0, seconds, seconds * fs, False)
# Generate a 440 Hz sine wave
note = np.sin(frequency * t * 2 * np.pi)
# Ensure that highest value is in 16-bit range
audio = note * (2**15 - 1) / np.max(np.abs(note))
# Convert to 16-bit data
audio = audio.astype(np.int16)
# Start playback
play_obj = sa.play_buffer(audio, 1, 2, fs)
# Wait for playback to finish before exiting
play_obj.wait_done()The above is the basic structure as an example from the web. It shouldn't be too difficult to change the AWG to use this. Naturally this has all the mac mini filters in the way.. but the same could be done using a PI etc.
After much gnashing of teeth - I managed to get the Ubuntu VM inside VirtualBox running on my Mac mini connected by ethernet to allow the connection from the SDS1104-E. The bode plot is random output as I've not actually got the probes connected to anything!
