DIY Marantz 7C

Your Matisse had much more potential than your marantz preamp, i think. Matiisse had better dynamic but using WiMA will make it sound harsh. Try to use other caps on the Matisse, it will have quite a different sound.

Dear CAT,

If budget is a concern, try Auricap, it will make the whole thing sound a lot different. It will cost you about  a few hundred dollars, the second stage output cap , you can use 3.3U 200V instead of 400V. Jensen is of course miles better.

The original circuit of marantz using 0.01 and 0.22 as the by-pass cap.Just bear in mind that  the original design was with early LP in mind, so everything under 70 hz was cut. I have played with the marantz circuit for more than 10 years, my experience is that if you are using modern caps, the original value of 0,22 will make the amp sound harsh. I suggest you to replace 0.01 with 0.1 and 0.22 with 2-3U.  i have play with kimper caps, the high are not smooth enough, and the MIT caps which is too hi-fi.
If you are aware that Sid Smith 7, the amp that sell for 30,000+ are using Auricap with the above suggested value. The top version is using Jensen silver cap ( 4K each) and selling for 100K. so, there is virtually no secret to good sound, a good design with good material.  Good design is no secret nowadays and the key is to get good material.  You kit supply with WIMA cap, which is not very match to tube in my opinion.

I had not try RIFA caps, however, a lot of factory like cello, Mark , using RIFA as by pass caps. My feeling is that it sound a little bit harsh on the highs like a lot of transistor amp. I had already replace those even though my DAC using RIFA caps.

Ladder type volume of  course had a significant difference in the sound. CAT using Dale resisitor so the sound is very neutral. while holco resistor and RMG resistor will give you a detailed and sweet sound. Most high value gears using ladder type volume. The  difference is more than the different of  $300 against $60. ha....ha..... All my pre-amp are using ladder type now. Actually William have some ready-made ladder volume pot with Dale resistor , you can buy direct from him. I think it is below $ 300.

WIllian is the admin of HiFiFever......

Cyrus,

Don't build this one, it sound so so, ask William to get you a real Marantz 7 kit from China, the pcb layout and it is using original value. or try Matisee reference.

Actually, it should not cost that much. I had build a Marantz 7 ( the real circuit with 膽穩壓，using auricap and Elna Cereine ,it cost about 3K without the tube.

LS7 sound quite different to Marantz 7, it is a matter of taste. LS7 sound like modern tube amp which have more dynamic, extension and faster. It does not sound like a tube amp. The default kit using bennic capacitor which need to be changed. For the Marantz 7, if appropriate run-in and with better parts, it is more musical and sound "thicker". Your power amp i also important because sometimes it is a mix and match.

A lot of people like GG, but I need manage to get really good sound from this circuit. It is quite simple in effect and good for really beginner. From a design point of view, marantz 7 is the best because the cathod follower will result in lower output impedence. I had not tried audio note m7 and conard johnson , so I am unable to comment on it.

C22 is basically a Marantz 7 with different value. I think Marantz 7 will be better.

I have a Jadis JP-200 half finished, I do not know whether your friend will be interested, you can finished it off  for him. I am using premium parts like MIT and Philips Cap, just like the original one. .......Please PM me to discuss if your colleagues interested. I have PCB, tube stabilizer, transformer and case available at the moment.

Oh, it is a ground different between two devices. You need to check whether your tube CDP and your pre-amp had ground the 水線 to the case of the device or some even connect to the 水線. It is better to connect both  水線 to the case.
For filament supply, there is normally two ways in reducing the hum sound, some will ground one filament, other method  will connect a high voltage ( say 100V) to the filament and float the filament from the ground, both ways should be ok to reduce hum.

For change the 12AX7 to 12AU7, it is not that simple as these tube had different operating condition. Need to change the bias resistor and the 陰極 電阻。I will check my circuit with me tonight and let you know.

no, i can really give you any comment as i have not finished the kit yet. But base on circuit design, Matisse is more dynamic and hifi and JP-200 should be more lay back and musical. It is really until you finish it and you do not really know how it sound. Does it sound chanllaging?

Wooden box is always a problem for grounding. Did you got any metal plate on the wooden box, you can ground the earth to the metal plate to replace interface. Alternative, you can remove the cap on the cpd and ground it to see it will better or not.

130V is too low. I suggest you to increase the plate voltage to 200v and use the orignal value of resistor. You will find the ' 動態" is much better. For power supply, it is better to use CLC rather than CRC and you will find the noise is much lower when you use CLC. About 10 H coke will be better and cost very low ( about $ 100 if you buy local).

CRC = Capacitor + Resistor + Capacitor
CLC = Capactior + Coke + Capacitor

Ways to reduce ripples in power supply.

ka ka ka....... yes , I mean choke.... instead of coke......ka ka ka....

One famous local manufacturer selling choke of 10H 100ma , for only $80 (about USd 10.00), Sound ok but of course not up to those japanese one like tango or tamura.

I know someone tried to use inductor but its effect is weak when compare to choke. I can help you to buy one or two .

Jensen Caps, @^@, No wonder it cost you 4K but it is worth every single cents.
I still have a Marantz 7 Broad, Any one interested ??? YOU can get the Board first build the power supply yourself.   I think you spent 3K, you will still get a decent sound using Auricap and Holoco or RMG resistor.  

CAT, better change the caps in the matisse broad too as it is really important and affect the sound.  Two output caps 47U 500V should also change to decent one as they have really big effect on the sound.

I buy it a year ago, the broad should cost about $100, ^-^, it should be quite a easy one as all resistor and caps are all stated in the Broad. I can tell you how the material and value affect the caps. It comes with a power supply board but i suggest you to use some others one.

Jensen or BHC but I perfer the sound of Jensen.

I do not know the Lite Broad, why do you ask Master 棠？ He should know about the Board.

You should direct wire from the power supply broad to B1 for left and right channel.
You should able to turn the Matisse Broad, what AC voltage you are inputing ? You can't  use the 1M to reduce the voltage.

If input 310V AC, then output will be 310V x 1.4 = 430V DC and 309V DC seemed but the range that adjusted by the power broad should be more than 15V. There may be something wrong with the borad. Look for whether the diode position is correct or whether LM317 is working or not. By the way, did you measure the voltage with loading ?

Yes, got to measure the voltage with loading, otherwise the voltage is not right. Besides, the resistor between b1 and b2 should be 4.7K, not 47K.