Search found 229 matches
- Fri May 07, 2021 7:41 pm
- Forum: Everyones Projects
- Topic: 45 SE
- Replies: 170
- Views: 41431
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...
- Mon Apr 19, 2021 5:00 pm
- Forum: Assorted Stuff
- Topic: Joseph Crowe
- Replies: 19
- Views: 7164
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...
- Tue Apr 13, 2021 4:28 pm
- Forum: Everyones Projects
- Topic: 2P29L Preamp
- Replies: 18
- Views: 9528
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...
- Tue Apr 06, 2021 5:11 pm
- Forum: Speakers
- Topic: PERSPEX QUASAR ver 2.0 prototype build
- Replies: 324
- Views: 127288
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 ...
- Mon Mar 15, 2021 6:43 pm
- Forum: General Vinyl
- Topic: Zenith Errors
- Replies: 15
- Views: 16200
Re: Zenith Errors
The Fozgometer incorporates a "LogRatioDetector" developed for surround processor steering logic circuits to measure channel separation. The LEDs show which channel is ON, the signal reading of the analog meter shows the amount(voltage?) of the signal. If left and right channel show the sa...
- Mon Mar 15, 2021 2:53 pm
- Forum: General Vinyl
- Topic: Zenith Errors
- Replies: 15
- Views: 16200
Re: Zenith Errors
Testrecord and Fozgometer is the only thing that really worked for me but is completely overprized. The sound improvement was very obvious. Shouldn't be too hard to build the circuit for a fraction of the resale price. https://www.dedicatedaudio.com/products/fosgate-fozgometer-azimuth-range-meter Th...
- Sat Mar 06, 2021 3:51 pm
- Forum: Assorted Stuff
- Topic: CCS topologies
- Replies: 3
- Views: 2523
Re: CCS topologies
But you can’t use a constant current sink on low transconductance valves. Ok, but my question was going in the direction of what difference it makes using a current regulator vs a voltage regulator. And JBroskie uses both together which makes it even more difficult to understand in case it is about...
- Fri Mar 05, 2021 3:54 pm
- Forum: Beginners
- Topic: Simple Active Low Pass Filter/Buffer
- Replies: 6
- Views: 9128
Re: Simple Active Low Pass Filter/Buffer
With miniDSP and measuring equipment the process would be ideally: 1. OB speakers in the final(expected) room position connected to the amps that will be finally used 2. miniDSP connected to the DAC (ideally miniSHARC before PCM DAC with I2s connection, or external unit), first selection of filters ...
- Wed Mar 03, 2021 3:42 pm
- Forum: Assorted Stuff
- Topic: CCS topologies
- Replies: 3
- Views: 2523
CCS topologies
Don't now if "topology" is the right term here. I was wondering if there is any noticeable difference in how it sounds using a voltage regulator vs a current regulator. Or: why would one use all those extra parts for replacing a 10k/2k (elysium) resistor if a TL738 could be used ? JB (2).p...
- Mon Mar 01, 2021 3:38 pm
- Forum: Everyones Projects
- Topic: 300B Headphone Amp
- Replies: 114
- Views: 52242
Re: 300B Headphone Amp
Nice development, Ray. Looking forward to hear more about how both DACs perform in comparison. I am building an OTL headphone amp for my studio(with the 6AS7, no NFB) and was wondering how you got to the two different output impedances (32/600ohms) with the MP circuit. Do you use output transformers...
- Mon Jan 11, 2021 4:04 pm
- Forum: Assorted Stuff
- Topic: Reel to reel
- Replies: 67
- Views: 25187
Re: Reel to reel
Not to be misunderstood: The +2dB were of course the settings for the peak levels not the general recording level.
- Mon Jan 11, 2021 3:12 pm
- Forum: Assorted Stuff
- Topic: Reel to reel
- Replies: 67
- Views: 25187
Re: Reel to reel
No "stupid questions"! An r2r machine looks cool and sounds cool. I had for many years an Akai GX-630DB and it was the highlight of my sound system. I recorded not only my vinyl for having a compilation of my favorite music but also for the sound. High speed at +2dB recording level produce...
- Fri Jan 01, 2021 6:16 pm
- Forum: Speakers
- Topic: SLOB project
- Replies: 318
- Views: 144202
Re: SLOB project
It looks like you are right! I did some more research and found this: “The phase control setting is a bit confusing and the operation is not explained well in the owners manual. The DCX uses the LP filter frequency setting (even if it's "Off") as the reference point for the phase adjustmen...
- Thu Dec 31, 2020 6:36 pm
- Forum: Speakers
- Topic: SLOB project
- Replies: 318
- Views: 144202
Re: SLOB project
I forgot to mention that I used the miniSHARC PEQs only for adjusting the frequency response of the room. I never tried the x-over option which would be a different thing regarding phase shift and filter types.
- Thu Dec 31, 2020 6:12 pm
- Forum: Speakers
- Topic: SLOB project
- Replies: 318
- Views: 144202
Re: SLOB project
Though measuring phase without the right kit is very difficult. Carma 4 for example shows magnitude and phase together. But even just by looking at the magnitude response one would see if there is a dip around the x-over point which would indicate a problem. I don't think the Ultradrive offers FIR ...