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resistor relay volume control preamp

Brab

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Jun 2, 2020
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I'm interested in the Topping L70 preamp. Are there other similar preamps with resistor relay based volume control (with remote) to consider preferably cheaper? thanks.
 
AFAIK, the L70 is the least expensive remote controlled Preamp with stepped volume control, that's currently available.
 
A resistor relay volume control preamp adjusts audio volume by switching resistors with relays for precise control and minimal signal distortion
precision and channel balance and easy remote control yes.
Distortion is not really determined by this.
 
precision and channel balance and easy remote control yes.
Distortion is not really determined by this.

At the end of the day, an ALPs motorized blue velvet (conductive plastics RK-27) is arguably a better choice.

I don't think I've ever had a failed one on my bench.
 
me neither. have seen relays and relay drivers fail ...:)

arguably, calibrated attenuation, channel balance, accuracy goes to the relay thingies at the cost of PCB space and power consumptions as well as mechanical noises.
 
I totally agree. Just don't ever use switch cleaner on one. Ask me how I know...
You have to use the right kind that does not affect the plastic film.
 
I'm interested in the Topping L70 preamp. Are there other similar preamps with resistor relay based volume control (with remote) to consider preferably cheaper? thanks.
I was trying to work out if the JDS Labs Element IV DAC & HP Amp in the latest ASR review had a relay switched resistors volume control (R2R) and I stumbled across this thread.
I've been trying to answer similar questions myself. R2R volume controls are the preserve of cost-no-object preamps costing tens of thousands of dollars.
They're expensive to make, and I think we should be grateful that Topping makes the L70 with R2R and performance that rivals the best preamps, too. We live in fine times.

The alternative Sabaj A10h has already been mentioned, but the Sabaj A20h is available. It doesn't have a preamp output, but you can use a TRRRS to XLR adapter.
The A20h has resistor ladder relays for volume control which should assure perfect channel balance.
 
There are pictures of its PCB, it's obvious that it does not.
Yes, I saw those, too. I was just saying how I came across this old thread.
No such thing. R-2R is an ancient AD/DA converter topology. Relay-controlled volume controls do not use R-2R ladders.
Yes, I know that, but it is a widely used expression. I'm not aware of a concise and accurate abbreviation to save tiresome seconds typing.
 
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Yes, I saw those, too. I was just saying how I came across this old thread.

Yes, I know that, but it is a widely used expression. I'm not aware of a concise and accurate abbreviation to save tiresome seconds typing.
Try "stepped analog". Includes both relay and rotary switch types, but excludes digital.
 
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