There is a big gap between the sound card type product kludged for test and measurement use and thee HP-TEK-K-H-R&S-SRS-AP type product that we can fill. We can fill that need and keep the cost low enough. Not dirt cheap but low enough. And, not be too hard to build or mfr.
Bob Cordell did it 30 years ago... filled the gap. But those switches were the killer. If the need is still there (it is) and we do this again, it will last 30 years as well.
Thx-RNMarsh
Bob Cordell did it 30 years ago... filled the gap. But those switches were the killer. If the need is still there (it is) and we do this again, it will last 30 years as well.
Thx-RNMarsh
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When the 725 was designed there were no other good solutions for switching so many close tolerance resistors. Its an extremely expensive solution. Creating a tuned notch filter with 1% bandwidth that us tunable from 10 Hz to 110KHz is a lot of steps. Using precision passive components so it is stable and accurate open loop adds to the challenges.
I don't see a reason for continuous tuning of a distortion analyzer. Spot frequencies are completely adequate for the electronic systems we deal with. And even a modest sound card is orders of magnitude better than any transducer I know of so fine for measuring speakers or other transducers.
As I suggested earlier a handful, no more than 5 or 6, fixed frequencies for testing distortion will show all that really is there to learn on electronic systems.
I don't see a reason for continuous tuning of a distortion analyzer. Spot frequencies are completely adequate for the electronic systems we deal with. And even a modest sound card is orders of magnitude better than any transducer I know of so fine for measuring speakers or other transducers.
As I suggested earlier a handful, no more than 5 or 6, fixed frequencies for testing distortion will show all that really is there to learn on electronic systems.
Maybe choose frequencies which are of interest to both acoustics and amp tests.
Thx-RNmarsh
Thx-RNmarsh
You may be able to get a manual from here KAI-Products information: Test & Measurement Instruments and Power Supplies who are the distributors for the Levear (Panasonic) audio analyzers in the US. I have a PDF of the VP7723 manual which may be similar. PM me with an e-mail and I'll send it. Its too big to upload.
Good to see others have started to try the VP-7xxx series of test gear. The VP-7xxx series are great machines and a bargain at the used prices... real sleeper test gear. At this moment in time I have a -22 and a -23 model if I can answer questions about them or corroborate something. .
-RNM
-RNM
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PM sent. Many thanks for the link, I have requested kikusuiamerica for documentation. Hope it works.
Totally agree. Magical device. Thanks for suggestion! I will ask, if I reach a deadlock.
yes. Impossible... the USA rep said he cannot give/get or sell us a manual. must be some intellectual property/strategic issues they are controlling... like protecting their industry and market.
So we either design and build our own or we buy new/used equipment and modify or use 24bit sound cards with add-on interfacing and add-on filters and add-on software etc with limited but still fairly useful results.
Thx-RNMarsh
So we either design and build our own or we buy new/used equipment and modify or use 24bit sound cards with add-on interfacing and add-on filters and add-on software etc with limited but still fairly useful results.
Thx-RNMarsh
I try, but without success. The answer from kikusuiamerica.com:
And later from PTT Company Limited (Tokyo):
I still waiting for your VP7723 manual and will be very thankful to you.
My email: kk [att] levelfive-audio.com
Thanks in advance!
Konstantin.
I have the Panasonic brand --- but the rear panel lable says who makes it for Panasonic. it is not manufactured by Panasonic. There is a mfr of these instruments and there are Brands - different. I don't know who controls the rights to the design. Even though it isn't sold new at this time... I would think a copy could still be found for us by Panasonic. or we get the Levear model and look at their manual/schematics even if it isn't exactly the same (or is it?). Anyway, it is quit a run-around. The Panasonic, Levear and National brands all appear to use similar design concepts to the ShibaSoku. With their own updates and added feature set (like IM etc). As these come with GPIB and other features which indicate they were used a lot in production invirnment.
Thx-RNMarsh
Thx-RNMarsh
yes -- very much into them all. I started with other brands and ended up finding the ShibaSoku but continue to want something fr everyone that is affordable and/or easy to make.
This and the A-P and QA400 threads are spin-offs of the mother one.
I havent seen one of your Megura... maybe others have -- but do you have pictures and its specs or web site?
Thx-RNMarsh
This and the A-P and QA400 threads are spin-offs of the mother one.
I havent seen one of your Megura... maybe others have -- but do you have pictures and its specs or web site?
Thx-RNMarsh
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