Power cable shielding for messy entertainment centers
Hi All, I am looking for AC power cables with shielding and a good bit of insulation so that they can lay next to source interconnects with minimal interference. I know the best solution is to avoid running interconnects and power in parallel, but sometimes furniture, room layout and practicality conspire against us.
The affordable cable I've found with good insultation also seems to have shielding with large gaps. Depicted below. Is this a problem? Is this shielding doing any good? Would I be better off just getting a regular shielded power cable and putting some hose/tubing around it to force some distance between the AC power and interconnects?
Thanks,
Joe
The affordable cable I've found with good insultation also seems to have shielding with large gaps. Depicted below. Is this a problem? Is this shielding doing any good? Would I be better off just getting a regular shielded power cable and putting some hose/tubing around it to force some distance between the AC power and interconnects?
Thanks,
Joe
FS: GroundSound DCN24 2x4 Digital Crossover DSP (Qty 3)
- By falconsprint
- Swap Meet
- 2 Replies
Attachments
Hello all
- By seanjammy
- Introductions
- 3 Replies
Hi everyone,
My name is Sean, I love in Johannesburg, South Africa. An avid enjoyer of HiFi, decided to beat the Covid blues by building some speakers.
My first couple of attempts (JE Labs OBs using Philips AD100, and a homebred made from a crate), as well as a shot of my main system below.
Browsing the forums has already been a great help. Look forward to being part of this community.
My name is Sean, I love in Johannesburg, South Africa. An avid enjoyer of HiFi, decided to beat the Covid blues by building some speakers.
My first couple of attempts (JE Labs OBs using Philips AD100, and a homebred made from a crate), as well as a shot of my main system below.
Browsing the forums has already been a great help. Look forward to being part of this community.
Ideas to improve a zero-field transformer based circuit
- By Elvee
- Equipment & Tools
- 24 Replies
I am currently trying to convert an old AC clamp meter into an instrument usable for all audio-frequency works.
The probe in question was an "Amprobe", probably made end '60s, early '70s and was part of a graphic recorder.
It is of a poor quality standard, and does not work as a real current transformer: its magnetizing inductance acts as a large part of the shunt, and it worked and was calibrated for a single frequency, 60 or 50Hz.
The detector used a selenium rectifier, which even at that time was already antiquated:
By adding a suitable electronic conditioning circuit, I hope to convert this piece of crap into something usable and accurate.
I have measured its characteristics: ~0.5H, DC resistance ~104 ohm.
Even with a perfect transimpedance input, this results in a LF cutoff >33Hz.
As I need 10x better, I have to compensate the winding resistance by a negative resistance.
Because of the poor shielding, I have opted for a balanced circuit:
R1, R5 define the gain and R3, 4, 6, 7 provide the negative resistance. R4 and R7 are non-inductive copper windings, to compensate the measurement windings.
The result looks attractive, with a response flat to under 1Hz, but that is in sim only: in reality, the circuit also needs to be DC-stable, which it won't be without additional measures.
The first idea to use a blocking cap in series with the winding is not practicable; the combination of low synthetic resistance with a large inductance and capacitance results in a huge VLF resonance.
An additional pole has to be introduced somewhere, but this is no simple task: if the pole has a frequency comparable to the one already present, it will create a large peak in the response.
The pole can be placed at a much higher frequency, but this will also kill the LF capability, and placing it at a much lower frequency results results in huge time-constants and bulky components.
There is another difficulty: for noise and dynamic range reasons, the range switching should be made directly at the transimpedance stage level.
This means switching the 4 resistors, plus the possible DC-blocking caps for each range, and I intend to implement 5 ranges: from 20mA to 200A.
That is a lot of contacts.
I opted for a tradeoff: the only switching at the TIA would be the unit: mA or A. The resistors would be 60 ohm or 60K.
The 3 subranges would be created downstream, by varying the gain. The 2mA range is probably not going to be usable, but it doesn't matter.
With the 60K, a capacitor would be inserted in series with the positive feedback resistor. This would still result in a DC gain >1000: awkward, but manageable:
With the 60 ohm, an additional trick is needed to avoid impossibly high capacitor values:
All of this could be made to work, but it is complicated, clumsy and inelegant.
There must be a cleverer way to implement it, but so far I couldn't think of one.
Any creative suggestion is welcome.
The circuit is essentially a zero-field circuit (the clamp is a transformer), but with the complication of multiple ranges
The probe in question was an "Amprobe", probably made end '60s, early '70s and was part of a graphic recorder.
It is of a poor quality standard, and does not work as a real current transformer: its magnetizing inductance acts as a large part of the shunt, and it worked and was calibrated for a single frequency, 60 or 50Hz.
The detector used a selenium rectifier, which even at that time was already antiquated:
By adding a suitable electronic conditioning circuit, I hope to convert this piece of crap into something usable and accurate.
I have measured its characteristics: ~0.5H, DC resistance ~104 ohm.
Even with a perfect transimpedance input, this results in a LF cutoff >33Hz.
As I need 10x better, I have to compensate the winding resistance by a negative resistance.
Because of the poor shielding, I have opted for a balanced circuit:
R1, R5 define the gain and R3, 4, 6, 7 provide the negative resistance. R4 and R7 are non-inductive copper windings, to compensate the measurement windings.
The result looks attractive, with a response flat to under 1Hz, but that is in sim only: in reality, the circuit also needs to be DC-stable, which it won't be without additional measures.
The first idea to use a blocking cap in series with the winding is not practicable; the combination of low synthetic resistance with a large inductance and capacitance results in a huge VLF resonance.
An additional pole has to be introduced somewhere, but this is no simple task: if the pole has a frequency comparable to the one already present, it will create a large peak in the response.
The pole can be placed at a much higher frequency, but this will also kill the LF capability, and placing it at a much lower frequency results results in huge time-constants and bulky components.
There is another difficulty: for noise and dynamic range reasons, the range switching should be made directly at the transimpedance stage level.
This means switching the 4 resistors, plus the possible DC-blocking caps for each range, and I intend to implement 5 ranges: from 20mA to 200A.
That is a lot of contacts.
I opted for a tradeoff: the only switching at the TIA would be the unit: mA or A. The resistors would be 60 ohm or 60K.
The 3 subranges would be created downstream, by varying the gain. The 2mA range is probably not going to be usable, but it doesn't matter.
With the 60K, a capacitor would be inserted in series with the positive feedback resistor. This would still result in a DC gain >1000: awkward, but manageable:
With the 60 ohm, an additional trick is needed to avoid impossibly high capacitor values:
All of this could be made to work, but it is complicated, clumsy and inelegant.
There must be a cleverer way to implement it, but so far I couldn't think of one.
Any creative suggestion is welcome.
The circuit is essentially a zero-field circuit (the clamp is a transformer), but with the complication of multiple ranges
Attachments
Dolby stereo CP200 in my home THX cinema
- By JBL 4645
- Analog Line Level
- 6 Replies
Attachments
-
67782258_10157287141145149_2406165405069475840_o.jpg -
67941115_10157287141655149_2925406593010892800_o.jpg -
67802809_10157287141475149_3485996272924491776_o.jpg -
69218134_10157331015830149_8765243371632459776_o.jpg -
67909816_10157303268035149_7541509143488626688_o.jpg -
69155451_10157306374610149_1331810075056013312_o.jpg -
67952024_10157306377660149_1123520817083187200_o (1).jpg -
80486418_10157648375150149_8672099798863577088_o.jpg -
67918550_10157287142455149_7394640920030740480_o.jpg -
82024082_10157716732190149_8123197450811867136_o.jpg
How to Configure a 7.1 PC Soundcard as an Active Stereo Crossover?
How to Configure a PC Soundcard as an Active Stereo Crossover?
Could the Asus STX II 7.1 sound card be used as an active crossover for driving a stereo 3 way speaker system with 3 stereo amplifiers?
My question is, is there a way to configure this card to work as a high fidelity Digital to Analog crossover that outputs 6 channels like this:
LL: Low Left (20 - 300 Hz) ---__ Rear Left RCA
LR: Low Right (20 - 300 Hz) ---__ Rear Right RCA
ML: Mid Left (300 Hz - 3Khz) __---__ Front Left RCA
MR: Mid Right (300 Hz - 3Khz) __---__ Front Right RCA
HL: High Left (3Khz - 20Khz) __--- Side Left RCA
HR: High Right (3Khz - 20 Khz) __--- Side Left RCA
If such a thing would be possible, then the Digital signal from the computer needs to be converted only once to analog via this 7.1 soundcard, and the three pairs (Low, Mid and High) could each go to three identical amplifiers after which the signales can go directly to the speakers, bypassing the analogue crossovers entirely.
In theorie this should be possible, with software.
But is it actually possible in reality??
- If not, then why not? Prove why its not possible.
- If yess, then in what way(s) you think it could/might?
- If you have any ideas or suggestions or tips, you are most welcome to share!
Could the Asus STX II 7.1 sound card be used as an active crossover for driving a stereo 3 way speaker system with 3 stereo amplifiers?
My question is, is there a way to configure this card to work as a high fidelity Digital to Analog crossover that outputs 6 channels like this:
LL: Low Left (20 - 300 Hz) ---__ Rear Left RCA
LR: Low Right (20 - 300 Hz) ---__ Rear Right RCA
ML: Mid Left (300 Hz - 3Khz) __---__ Front Left RCA
MR: Mid Right (300 Hz - 3Khz) __---__ Front Right RCA
HL: High Left (3Khz - 20Khz) __--- Side Left RCA
HR: High Right (3Khz - 20 Khz) __--- Side Left RCA
If such a thing would be possible, then the Digital signal from the computer needs to be converted only once to analog via this 7.1 soundcard, and the three pairs (Low, Mid and High) could each go to three identical amplifiers after which the signales can go directly to the speakers, bypassing the analogue crossovers entirely.
In theorie this should be possible, with software.
But is it actually possible in reality??
- If not, then why not? Prove why its not possible.
- If yess, then in what way(s) you think it could/might?
- If you have any ideas or suggestions or tips, you are most welcome to share!
