Search found 225 matches

by Wolfgang
Tue Sep 21, 2021 5:15 pm
Forum: Computer Audio
Topic: Streaming question
Replies: 2
Views: 451

Re: Streaming question

It's obviously an MP3 file (32kHz, filter cut off at 16kHz) upsampled to wav . It still is MP3quality but is recognized as as 44.1/16 wav. I don't want to draw false conclusions like whether that's Amazon's general policy or not but it's not CD quaity and my test recordings looked like that. I don't...
by Wolfgang
Mon Sep 20, 2021 1:35 am
Forum: Computer Audio
Topic: Streaming question
Replies: 2
Views: 451

Streaming question

I am testing the amazon streaming service and signed up for HD/ultra HD which means that I get their best CD quality streaming. I am recording the songs I like in my studio and play them on my main system as I have no internet access in my music player PC. I realized after a while that the recorded ...
by Wolfgang
Wed Jun 09, 2021 4:41 pm
Forum: Everyones Projects
Topic: 45 SE
Replies: 170
Views: 18394

Re: 45 SE

What's discussed in this article makes even more sense(to me) when "sound" of transformers or psu" becomes a topic.

https://richardsears1.wordpress.com/201 ... teraction/

A discussion would be interesting.
by Wolfgang
Tue May 25, 2021 4:10 pm
Forum: Valves
Topic: SRPP stage useing a 5670
Replies: 19
Views: 5400

Re: SRPP stage useing a 5670

What is the advantage of useing a SRPP input stage as apposed to a normal input stage None, if you don’t need more than let's say 30% of the idle current of a simple SE input stage into the load of the next stage. Simplicity of the circuit and the best suited tube for the job is more in this case I...
by Wolfgang
Wed May 19, 2021 3:44 pm
Forum: Beginners
Topic: Restacking An Output Transformer.
Replies: 60
Views: 7085

Re: Restacking An Output Transformer.

none of that affects the choice of core material Correct. Obviously a misunderstanding on my side! I tried to sort it out and this is where I am at right now. Hope this is correct. 1. High permeability and low hysteresis (amorphous cores) would be good for better linearity and lower harmonic distor...
by Wolfgang
Mon May 17, 2021 12:41 am
Forum: Beginners
Topic: Restacking An Output Transformer.
Replies: 60
Views: 7085

Re: Restacking An Output Transformer.

Yes, I wasn't clear enough. I am comparing parafeed or not considering that NO core material is NOT affected by DC. Maybe I simply misinterpreted this : "The purpose of the airgap is to accept the DC current of the output tube without saturating the core, leaving enough headroom for the sound s...
by Wolfgang
Sun May 16, 2021 7:06 pm
Forum: Beginners
Topic: Restacking An Output Transformer.
Replies: 60
Views: 7085

Re: Restacking An Output Transformer.

Why not? I was referring to some Lundahl OPT information, maybe I misinterpreted it regarding what I called compromises. But it seems that one has to make decisions -which looks like a compromise to me - regarding output wattage,max inductance,lowest frequency and loss (doesn't that refer to the co...
by Wolfgang
Sun May 16, 2021 3:47 pm
Forum: Beginners
Topic: Restacking An Output Transformer.
Replies: 60
Views: 7085

Re: Restacking An Output Transformer.

What would happen if we used the Parafeed cap as part of a crossover? An issue could be that the OPTs primary has a much higher inductance than what would be needed for L for using the OPT as part of x-over filter. Personally I wouldn't trust this kind of operation -even if it were possible - becau...
by Wolfgang
Fri May 14, 2021 3:44 pm
Forum: Beginners
Topic: Restacking An Output Transformer.
Replies: 60
Views: 7085

Re: Restacking An Output Transformer.

Parafeed with CCS is probably the best way because a very high quality inductor for the full audio spectrum must be also very expensive and maybe hard to find. The challenge is to find a good compromise with the plate voltage and idle current so that the CCS doesn't have to operate at crazy high B+.
by Wolfgang
Mon May 10, 2021 8:38 pm
Forum: Everyones Projects
Topic: 45 SE
Replies: 170
Views: 18394

Re: 45 SE

Thanks for the answers. I guess I simply will take my chances and start somewhere .
by Wolfgang
Mon May 10, 2021 4:17 pm
Forum: Everyones Projects
Topic: 45 SE
Replies: 170
Views: 18394

Re: 45 SE

I still couldn't figure out how you made adjustments for the load impedance for all the different tube types which you have used together with the same OPTs and speaker impedance. Did you calculate the details, measure the results? Or did everything simply fall into some kind of "grey zone"...
by Wolfgang
Fri May 07, 2021 7:41 pm
Forum: Everyones Projects
Topic: 45 SE
Replies: 170
Views: 18394

Re: 45 SE

...use proven engineering principles... THERE IS NO MAGIC. I was kind of hoping that the OPT topic would come up at some point because I am considering to build a 2A3/45 switchable SE amp based on a Loftin-White circuit.Shouldn't the quality of the OPT be #1 on the list if we talk about "prove...
by Wolfgang
Mon Apr 19, 2021 5:00 pm
Forum: Assorted Stuff
Topic: Joseph Crowe
Replies: 19
Views: 2833

Re: Joseph Crowe

And what about cancelling distortion (more or less ) using a SE tube amp and a single moving coil speaker with reversed polarity as described in this article (Why SE tube amps?)? Also explains why speaker systems with active x-overs sound generally better. https://www.audiopax.com/e/Article.html I c...
by Wolfgang
Tue Apr 13, 2021 4:28 pm
Forum: Everyones Projects
Topic: 2P29L Preamp
Replies: 16
Views: 2804

Re: 2P29L Preamp

Interesting approach. Basically some kind of a simple active x-over without the options for adjusting and fine tuning. The Muse volume control adds so many opamps that one could use a good active analog x-over and would get the same impact of solid state (if that's a concern) but with all the option...
by Wolfgang
Tue Apr 06, 2021 5:11 pm
Forum: Speakers
Topic: PERSPEX QUASAR ver 2.0 prototype build
Replies: 195
Views: 42541

Re: PERSPEX QUASAR ver 2.0 prototype build

Cathode bypass cap and output cap changes will create some kind of a shelving filter curve which is not useable for xo purpose. A third option that hasn't been discussed is a simple filter in the NFB line but it's also rather a tone control than a real filter suitable for x-overs. Just another idea ...