I finished my Pearl II tonight. Well, almost, as one last improvement I will replace the rectifier bridges in the PSU with discrete LQA06T300 diodes.
Mine has the following changes compared to the original schematic:
R20 set for 100 Ohm load
R10 lowered to 4K7 to get voltages right around Q3 (due to my particular quad of 2SK170's)
R14 lowered to 680 Ohm for approximately 58.5dB gain.
Some pictures:
Inside the box
Front:
Back:
Mine has the following changes compared to the original schematic:
R20 set for 100 Ohm load
R10 lowered to 4K7 to get voltages right around Q3 (due to my particular quad of 2SK170's)
R14 lowered to 680 Ohm for approximately 58.5dB gain.
Some pictures:
Inside the box
An externally hosted image should be here but it was not working when we last tested it.
Front:
An externally hosted image should be here but it was not working when we last tested it.
Back:
An externally hosted image should be here but it was not working when we last tested it.
Nice tidy job Wellerman.
I think I could take a few tips from the way your's is wired a redo mine tomorrow .
I took my board ground to a chassis star ground then to the TT ground . I still have problems with noise ,but have ordered ZTX and ZVP to replace the ones in the duff board .
I double checked the TT yesterday and couldn't find any issues .
Just gotta keep going
Where should I take the LED power from ?
Cheers R
I think I could take a few tips from the way your's is wired a redo mine tomorrow .
I took my board ground to a chassis star ground then to the TT ground . I still have problems with noise ,but have ordered ZTX and ZVP to replace the ones in the duff board .
I double checked the TT yesterday and couldn't find any issues .
Just gotta keep going
Where should I take the LED power from ?
Cheers R
Bangle Version of a DustBuster ?
6L6 - now THAT is cruel !! "Bangleized" in my lexicon means beaten with an ugly stick !!
We've got an E350, which has the best sound I've ever heard in an automobile. I'd like a CLS550, but they are a little too dear these days. I'd REALLY like a McLaren MP4-12C, but they are very dear indeed. Oh well.
6L6 - now THAT is cruel !! "Bangleized" in my lexicon means beaten with an ugly stick !!
We've got an E350, which has the best sound I've ever heard in an automobile. I'd like a CLS550, but they are a little too dear these days. I'd REALLY like a McLaren MP4-12C, but they are very dear indeed. Oh well.
As far as I can tell everything works fine. It sounds neutral, and very good. I still have to compare it to the phono stage in my Sony amp.
The lettering I ordered in a shop specializing in self adhesive lettering (superletters.nl). They are -how appropriate- matt black vinyl. Each word is one item, so that helps in getting it neat.
@richluvsound: I took the power from the led straight from the DC in, in this case the 0 and -35V. 1 have 2 10k resistors on the led. The led in the PSU takes its power from the 0 and +35V, so with both leds combined I can check both the positive and negative rail.
On another note, our local audio group had a phono stage shootout on Sunday.
We used a Thorens TD-160 Super with a Magnepan Unitrac-I and Dynavector 23R into the phono preamp being evaluated. Then into a line level input on an Audio Research SP-9 II feeding a Mirage BPS-150i sub, and the sub out to a McCormack DNA-1 amp to Magneplanar MG-IIIa speakers.
The phono preamps were my Pearl 2, a Musical Surroundings Phenomena, a Heed Quasar, and a Crown DL-2.
The Pearl came out the clear winner, with a balanced, natural tube-like sound. The Heed and Phenomena tied, with the Crown coming in 4th. The Heed's owner, who can hear nuances I can't, will be looking to obtain a Pearl 2 soon.
We used a Thorens TD-160 Super with a Magnepan Unitrac-I and Dynavector 23R into the phono preamp being evaluated. Then into a line level input on an Audio Research SP-9 II feeding a Mirage BPS-150i sub, and the sub out to a McCormack DNA-1 amp to Magneplanar MG-IIIa speakers.
The phono preamps were my Pearl 2, a Musical Surroundings Phenomena, a Heed Quasar, and a Crown DL-2.
The Pearl came out the clear winner, with a balanced, natural tube-like sound. The Heed and Phenomena tied, with the Crown coming in 4th. The Heed's owner, who can hear nuances I can't, will be looking to obtain a Pearl 2 soon.
No surprise to those of us who have one!
Get him to buy the boards ASAP, to get the ball rolling. Then help him with as much as you can and/or he needs.
We will then have another convert to DIY.
He did say it was the "clear" winner.
jeff
He did. A little understated. It did not 'crush' or beat to a bloody pulp (6L6). HaHa. Now I am being dumb, breaking the cardinal rule of splitting hairs on the Internet. All good.
Got home late last night a Mouser box awaiting. Hopefully I can wrap up my Pearl 2 this weekend. Took advantage of a sale at Music Direct - I should have a bunch of new records arriving today. Need a new phono stage!
The Heed's owner perked up and knew he was hearing something special about 3 seconds into the first track.
I think you could say it was a crushing.
I almost wanted to take today off to finish my Pearl 2. I am running a Pyle PP999 right now - bought in September after my daughter showed interest in my records and my old record player from high school. It had not run in over 20 years. Got a new belt, cheap AT cartridge, the Pyle. Fast forward 5 months, built an F5, bought a Rega TT, building a Pearl 2, record shipments and Mouser boxes coming every week.
My only vice, I am letting it ride.Safe to say the Pyle will get a nuclear annihilation from the Pearl 2?
Replacing the Yamaha HT Receiver, using it as a Pre-Amp out to the F5 made a big difference. Most 'average' listeners would say my current rig sounds great. Compare to a digital source, and it is obvious there is room for improvement on the phono side. 6L6 and others have been polite in saying my Rega Bias 2 cartridge sucks compared to other choices. That may be a future bottleneck after I get the Pearl 2 going.
I also plan on building a B1 buffer pre-amp, it will be interesting to observe the improvements (hopefully) as I upgrade each element. I have Polk TSi300s, OK for the money - another candidate for an upgrade. Thinking a Troels TQWT if I can realistically find the time to build.