modifications

Short Version: I want to know what basic measurements I should take (before and after making changes) to get a decent picture of how a given speaker is performing beyond what my less educated ears tell me. Long Version: I have 4 sets of vintage speakers from the 1970s that really should get a...

Part 1: Random "Popping" Noise This 771 exhibited random "popping" noise in both channels; measurement of the DC offset at the speaker outputs, demonstrated that the reading would fluctuate widely, reaching at times, several hundred mVs. This behavior was independent of input source and was...

I have done almost every modification found on this site for my AU-9500. (film caps where applicable, new electrolytics throughout, on-semi small signal transistors) While It has come out quite nice, I did not change the outputs (2SA909/2SC1886) or the pre-driver transistors on the F-2029 driver...

There is no DC offset adjustment on this device and Im trying to figure out how to correct the issue. Im getting -17 mv on the left channel and +35 mv on the right. Here is the circuit:

Hi, I’m trying to figure out how many ceramic caps to add and where to add them for noise reduction in the 4-ch section on my Sansui QRX-9001. I’m not having a lot of luck here. Anyone know/willing to help walk me through it/and or have pictures with the ceramics in place?

This is really part 2 of another loong post incorporating the issue of rumble. https://audiokarma.org/forums/index.php?threads/a-properly-operating-lenco-does-not-rumble.895835/#post-13331920 Another common bit of misinformation being freely dispensed by self-appointed :bowdown:‘experts’...

Ever since picking up a pair of technics sb-7000a speakers I've completely dismissed other speaker designs that utilize a flat baffle or non mirrored driver configuration. Up until my acquisition of the technics speakers I had never experienced stereo imaging. I had heard of it and read lengthy...

I have recently acquired an SX-838 in splendid physical condition. I love the looks (not that important), but the sound has less bottom than I would hope for. Hence a bit less of a soundstage and sonic headroom than I would like. Otherwise, excellent sound reproduction. Does anyone know of any...

Hi, First time poster. I've started cleaning up and recapping a Marantz 1030 as a summer project. It's going well. However, one of the things I'd like to do - due to its relative ease - is upgrade the power supply to a better level of regulation. To do this I'm going to replace the resistor to...

I've been playing a while with my Thorens TD-165. I added damping material to the inside of the plinth walls, to the bottom of the faceplate, and lately even to the bottom of the sub-chassis (also around the bearing well) - using a combination of adhesive tar sheets and white tac. I have been...