Not much special here, for the life of me I can't figure out why no one sells the old 5534 external JFET trick as a little module (maybe they do). Can't see this doing any worse.
Yeah, I'm not remembering anything obnoxious about it, just wondering what utility it had. No matter, the quoted part is more salient in the end. Part of me is curious the limits of human performance but that's independent of the fact that I can quite well enjoy music out of earbuds using the headphone out of my laptop.
The best thing I could do here is get myself a step-down transformer to not be blown out of the water by the time the volume hits 10%. Regain a couple bits of resolution.
Thanks Ed for the reminder that this stuff is supposed to be enjoyable.
As in all science - continuous work keeps modifying conclusions and fine tuning the process. There are much more comprehensive and newer work available.
I am not in my home office/computer but I have given the source/name of the latest and greatest book on hearing et al some time ago here.
There are 2 parts over here in DIY land --- what you hear or think you hear and designing the best you can and learning from it.
At one point in this life long process --- I decided to go direct and record my owm music for a reference source. The 30 ips 1/2 track Revox A77 was the machine..... condenser mics et al. One advantage of recording your own music is you know what it sounded like acoustically because you were there and know how the recorder/mic changed it. Never the less, the LP or CD was the issue to see how they differed..... and yes one recording was made into LP ($$).
The difference in sound quality was amazing! Very clean and accurate compared to commercially released sources. And, i could run the tape thru an inverse RIAA for testing LP systems.
This started me to think --- what in the recording side changes the sound so much..... recently, I returned to that question. However, now we can do direct from Master recording downloads and this question is moot now.
As for distortion -- as i said before - both an intellectual exercise but also to keep accumulated distortions from studio/mic to playback in home... requires a very low level of noise and distortion per amplifying stage everywhere in the process. or accumulated distortion can/will be audible. By making my own master tapes I concluded a lot is messed up on the recording side (not counting deliberate affects added).
THx- RNMarsh
Data General, now that brings back memories of my first laptop, floppy disk and all.
If I remember correctly Bongiorno went on to found Sumo electronics, they made some damned nice sounding amplifiers, hate to say it but I liked the Sumo much more than my Parasound, a definite cut above the Parasound in sound quality.
If I remember correctly Bongiorno went on to found Sumo electronics, they made some damned nice sounding amplifiers, hate to say it but I liked the Sumo much more than my Parasound, a definite cut above the Parasound in sound quality.
Sumo
Never did an A/B with the Parasound but as far as the Sumo goes, I'll drink to that!
PM me if you're interested. The noise floor is lower with messages. It also seems to echo a bit in certain forum venues....
Never did an A/B with the Parasound but as far as the Sumo goes, I'll drink to that!
PM me if you're interested. The noise floor is lower with messages. It also seems to echo a bit in certain forum venues....
Maybe the few thousand cheap opamps the signal goes through in recording along with hundreds of feet of el cheapo patch cord. One thing you didn't mention was mic placement which can take days in the studio. Also some mic are perter for some situation. I don't think the recording medium alone cold do it all.
George,
I'm thinking this must have been around 1990 or so when I used those Sumo amps. I can't imagine that they were running in pure class-A, they made way to much power for that if I remember correctly. I think they were around 200 watts per channel at 8 ohms if memory serve me at all.
I'm thinking this must have been around 1990 or so when I used those Sumo amps. I can't imagine that they were running in pure class-A, they made way to much power for that if I remember correctly. I think they were around 200 watts per channel at 8 ohms if memory serve me at all.
Most probably the “Andromeda” then
The “Nine” was of lower power (~60W@8 Ohm)
(attached extract from "Nine", causion on earthing is applicable to all their amplifiers)
George
Attachments
Spectrum analyzer?
Slightly OT:
I am looking for a spectrum analyzer to let me dig into switching noise etc in switching power supplies and class D stuff. My audio equipment takes care of the 1st 100kHz, so I really need an 'RF spectrum analyzer'.
I found a very nice one, also affordable, at Rhode & Schwartz:
http://www.batronix.com/pdf/Rohde-Schwarz/FPC1000/FPC1000_Datasheet_EN.pdf#page=14
About 1.5k here in old Europe, a testament how the Far East products have forced the traditional manufacturers to follow suit with low cost yet high performance.
The problem I have is that all this equipment has 50 ohms inputs. I understand where that comes from, but I'd rather have either a switchable 50 ohms/high impedance, or a high impedance input buffer or something like that. Several vector network analyzers have switchable 50 ohms / 1Meg inputs, for example.
Do any of you know whether there is a solution to this or am I chasing ghosts?
Jan
Slightly OT:
I am looking for a spectrum analyzer to let me dig into switching noise etc in switching power supplies and class D stuff. My audio equipment takes care of the 1st 100kHz, so I really need an 'RF spectrum analyzer'.
I found a very nice one, also affordable, at Rhode & Schwartz:
http://www.batronix.com/pdf/Rohde-Schwarz/FPC1000/FPC1000_Datasheet_EN.pdf#page=14
About 1.5k here in old Europe, a testament how the Far East products have forced the traditional manufacturers to follow suit with low cost yet high performance.
The problem I have is that all this equipment has 50 ohms inputs. I understand where that comes from, but I'd rather have either a switchable 50 ohms/high impedance, or a high impedance input buffer or something like that. Several vector network analyzers have switchable 50 ohms / 1Meg inputs, for example.
Do any of you know whether there is a solution to this or am I chasing ghosts?
Jan
Has anyone tried the (now EOL) BF862 with 5534? I looked but couldn't find anything. Seemed an obvious pairing.
The Agilent 89441A vector signal analyzer has 50/1Meg inputs,
but it is a 6HE boat anchor and at the R&S price point hard to justify.
50 Ohm inputs are dangerous in AF, I have killed the input of my
SNA-33 spectrum analyzer, 20 Hz to 30 GHz @ 1 Hz BW with AF
measurements.
Using the active probes of the scopes (both TEK & Agilent) was
a disaster. IMD and noise without end.
So you'll probably end up with an external preamp for the "mild RF"
range. It's cheap to change a burnt FET op amp. I run the stage
that drives the SA input on +/- 5V, that should avoid killing 50R inputs.
regards, Gerhard
but it is a 6HE boat anchor and at the R&S price point hard to justify.
50 Ohm inputs are dangerous in AF, I have killed the input of my
SNA-33 spectrum analyzer, 20 Hz to 30 GHz @ 1 Hz BW with AF
measurements.
Using the active probes of the scopes (both TEK & Agilent) was
a disaster. IMD and noise without end.
So you'll probably end up with an external preamp for the "mild RF"
range. It's cheap to change a burnt FET op amp. I run the stage
that drives the SA input on +/- 5V, that should avoid killing 50R inputs.
regards, Gerhard
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an active buffer probe...... High Z probe tip to 50 Ohm out. HP made some.... I have one for same reason you want --- high z in and 50 Ohm out to analyzer. Gerhard idea is good.
-RM
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I do own a Tek P6245 1.5Ghz, 1pF 1:10 probe with the probe power supply 1103. I used it with the Bode 100. Great probe but it has a low level hum. I am not sure whether it comes from the probe or from the power supply. Maybe put in a Silentswitcher ;-)
It also has the undesireable 20dB atten.
What is that HP type?
I really don't need GHz BW, 100MHz is probably more than enough.
Jan
It also has the undesireable 20dB atten.
What is that HP type?
I really don't need GHz BW, 100MHz is probably more than enough.
Jan
Hi Jan,
Hi Z inputs aren't normal in the RF enviroment you seek. What might work is a newer digital 'scope with > 12 bit resolution. The FFT function might do what you need, and of course it doubles as your oscilloscope. The only advise I can give you is unless this 'scope costs > $20K, keep your analog 'scope on the bench as well. Expensive digital oscilloscopes will replace an analog scope, but the less expensive ones really only try with varying degrees of success. You might find a Keysight 'scope < $10K that will do the job, but really you should just keep your analogue 'scope on the bench. Remember that with digital 'scopes, you should have 5X the bandwidth of the highest frequency you expect to deal with.
One massive advantage with a Keysight 'scope is that the analogue section has the bandwidth of the highest frequency scope in that series. That means you don't have to worry about the signal analogue stage -3dB down point - unless you buy the top of the line. With a license later on, you can extend the bandwidth if you discover you need more. So you aren't stuck with something to sell in order to update your abilities.
-Chris
Hi Z inputs aren't normal in the RF enviroment you seek. What might work is a newer digital 'scope with > 12 bit resolution. The FFT function might do what you need, and of course it doubles as your oscilloscope. The only advise I can give you is unless this 'scope costs > $20K, keep your analog 'scope on the bench as well. Expensive digital oscilloscopes will replace an analog scope, but the less expensive ones really only try with varying degrees of success. You might find a Keysight 'scope < $10K that will do the job, but really you should just keep your analogue 'scope on the bench. Remember that with digital 'scopes, you should have 5X the bandwidth of the highest frequency you expect to deal with.
One massive advantage with a Keysight 'scope is that the analogue section has the bandwidth of the highest frequency scope in that series. That means you don't have to worry about the signal analogue stage -3dB down point - unless you buy the top of the line. With a license later on, you can extend the bandwidth if you discover you need more. So you aren't stuck with something to sell in order to update your abilities.
-Chris
I'm sure the Tek cost more than the R&S spectrum analyzer...:-(
But the scope solution Chris mentioned may be a solution, I will look into that when I get home (am at the BE cost atm). I have n Agilent low cost digital scope, 70MHz BW, not sur about the resolution but certainly not more than 10 bit.
I also have a TiePie HS3 which can run at 14 bit up til 10MHz iirc.
So, thanks for the ideas - more testing to do!
jan
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