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#91
Headphone amplifiers / Re: QRV-08 power up
Last post by svarthvitt - December 25, 2018, 07:55:28 PMYes, the resistors are 470k, and the opamps are in the right direction.
#92
Headphone amplifiers / Re: QRV-08 power up
Last post by peranders - December 16, 2018, 10:48:12 AMThe R29 should be 470 kohm. IS it really this value? Is the opamp soldiered in the right direction?
#93
Headphone amplifiers / Re: QRV-08 power up
Last post by svarthvitt - December 15, 2018, 08:57:42 PMheaveno again,
I tried making this amplifier work again. I replaced some parts and looked over everything again once more. I really cannot find the fault here.
I tried filming the amplifier with a thermal camera, and BR1 and BR4 are running really hot. None of the resistors or silicone in the middle seems to heat up, except E29 and R29.
Does this help at all? Any other input on what I could try? I really want this thing running.
Regards,
Svarthvitt
I tried making this amplifier work again. I replaced some parts and looked over everything again once more. I really cannot find the fault here.
I tried filming the amplifier with a thermal camera, and BR1 and BR4 are running really hot. None of the resistors or silicone in the middle seems to heat up, except E29 and R29.
Does this help at all? Any other input on what I could try? I really want this thing running.
Regards,
Svarthvitt
#94
Headphone amplifiers / Re: QRV-08 gain reduction
Last post by peranders - October 30, 2018, 07:05:41 PMR14 and E14 can be changed. 330 ohms will set the gain to 2.
#95
Headphone amplifiers / QRV-08 gain reduction
Last post by Discom - October 29, 2018, 09:59:22 AMI've completed the QRV-08 a few months ago and it has playing happily ever since. You weren't kidding when you said it reveals poor recordings. I'll post a picture when I get around to taking one.
I've found the standard gain of 4 to be too high with an AMB gamma 3 and a set of HD650s. Which resistors should I change to reduce the gain, and what values would you recommend for a gain of 2 or 1 respectively?
#96
Headphone amplifiers / Re: Using QRV-08 as a Preamp
Last post by chinook9 - July 24, 2018, 04:12:51 PMThank you P-A. I suspected as much but I wanted to confirm it.
The original enclosure I used is a bit too small and I have not completed a neat installation. I recently received a slightly bigger enclosure and I may have room to put in RCA preamp-out jacks.
The QRV-8 sounds as good as a preamp as it does with headphones.
Thanks again
Brian
The original enclosure I used is a bit too small and I have not completed a neat installation. I recently received a slightly bigger enclosure and I may have room to put in RCA preamp-out jacks.
The QRV-8 sounds as good as a preamp as it does with headphones.
Thanks again
Brian
#97
Headphone amplifiers / Re: Using QRV-08 as a Preamp
Last post by peranders - July 24, 2018, 07:32:26 AMThe amp can be used as a preamp.
#98
Headphone amplifiers / Using QRV-08 as a Preamp
Last post by chinook9 - July 23, 2018, 11:12:47 PMheaveno P-A!
I have been enjoying my QRV-08 for a while now. I haven't put it in its final enclosure but I will do so this winter. I'll post a picture to Facebook then.
I read on a forum that someone was using their QRV-08 as a preamp. I tried my QRV-08 as a preamp running the headphone output through a series of adapters to the inputs on a Krell KSA-100 into Thiel CS3.6 speakers. The system sounds the best it ever.
Is using the QRV-08 as a preamp OK or might I cause problems in the QRV-08? I only have to turn the volume control about 1/3 rotation to get high volume.
Thank you,
Brian
I have been enjoying my QRV-08 for a while now. I haven't put it in its final enclosure but I will do so this winter. I'll post a picture to Facebook then.
I read on a forum that someone was using their QRV-08 as a preamp. I tried my QRV-08 as a preamp running the headphone output through a series of adapters to the inputs on a Krell KSA-100 into Thiel CS3.6 speakers. The system sounds the best it ever.
Is using the QRV-08 as a preamp OK or might I cause problems in the QRV-08? I only have to turn the volume control about 1/3 rotation to get high volume.
Thank you,
Brian
#99
Headphone amplifiers / Re: QRV-03 question
Last post by peranders - May 05, 2018, 01:27:58 PMSent :) If you want the patent document, I have it. let me know if you want it.
#100
Headphone amplifiers / Re: QRV-03 question
Last post by krainov - May 05, 2018, 11:35:17 AMYes, please! Send it to krainovrv(at)yandex.ru